Cerebral Lateralisation for Emotion Processing of Chimeric Faces in Individuals with Autism Spectrum Disorder
autism spectrum disorder, cerebral lateralisation, emotion processing, adults, children, chimeric faces task
Many studies have suggested that typical lateralisation for emotion processing tasks, such as facial emotion recognition, is lateralised to the right-hemisphere, with different emotions eliciting differing strengths of lateralisation (Bourne, 2010). However, there has been much debate as to the lateralisation of individuals with autism spectrum disorder (ASD) (Ashwin et al., 2005; Shamay-Tsoory et al., 2010). This study assessed the cerebral lateralisation of 30 adults with ASD, five children with ASD, 435 neurotypical adults and ten neurotypical children in a chimeric faces task, and aimed to identify whether the atypical lateralisation seen in children with ASD persists into adulthood (Taylor et al., 2012). Furthermore, the study aimed to identify whether lateralisation strength is affected by the emotion of the facial stimuli. No emotion- or age-related change in lateralisation was found, however, participants with ASD demonstrated a weaker right-hemispheric lateralisation compared to neurotypical participants. Therefore, this study supported the concept that individuals with ASD show atypical lateralisation which persists into adulthood, however, no evidence was found to support the concept that different emotions elicit different strengths of lateralisation.
Method Participants Data from a total of 481 participants with native level English proficiency (or age expected language development in children), normal or corrected-to-normal vision and no history of neurological disease or hearing loss were analysed for the current study (Table 1). Participants in the group ‘adults with ASD’ (N = 30; age: M = 30.17, SD = 9.85) were recruited through adverts on social media, through Prolific Academic (www.prolific.co), and through word of mouth. Participants in the groups ‘children with ASD’ (N = 5; age: M = 6.8, SD = 1.48) and ‘neurotypical children’ (N = 11; age: M = 7.0, SD = 1.90) were recruited through primary schools and word of mouth (Brooks, 2023), and parents of potential child participants were required to email a researcher to express their interest in participation. Participants in the group ‘neurotypical adults’ (N = 435; age: M = 29.44, SD = 8.03) were recruited through Prolific Academic (www.prolific.co) as part of a larger online behavioural laterality battery (Parker et al., 2021). Of the 481 participants who took part in the study, 32 were excluded during the data cleaning process (see Table 1 and Data Analysis for further information). Measures As part of the study, a series of questionnaires were administered to collect information about the participants to ensure that individual differences could be accounted for. Participants were asked to complete the study and its associated questionnaires and tasks prior to beginning the main chimeric faces task, and were requested to use a desktop or laptop computer for the entirety of the study. For the ‘neurotypical children’ and ‘children with ASD’ groups, parents were asked to complete the questionnaires on behalf of the children and were asked to be present for the tasks, which were completed during a Microsoft Teams call with a researcher. The study was completed online using the Gorilla Experiment Builder (www.gorilla.sc), a cloud-based tool for collecting data in the behavioural sciences. Demographic Questionnaire The demographic questionnaire asked participants their age, gender, length of time in education (in years), language status, two questions assessing handedness (“Which is your dominant hand? / Which hand do you prefer to use for tasks such as writing, cutting, and catching a ball?”) and footedness (“Which foot do you normally use to step up on a ladder/step?”), and two eye dominance tests (Miles, 1929; Porac & Coren, 1976). Participants were also asked whether they had a diagnosis of any developmental disorders, including ASD, dyslexia, attention deficit hyperactivity disorder or a language disorder (such as 'developmental language disorder' or 'specific language impairment'). For each diagnosis, participants had the option to answer “Yes”, “No”, or “Prefer not to say”, with the exception of ASD which also had the option to answer “No but I am self-diagnosed”. At this point, participants were sorted into their groups based on age (‘children’: five- to 11-years-old; or ‘adults’: 18- to 50-years-old) and ASD diagnosis (‘with ASD’, or ‘neurotypical’). Adults with a self-diagnosis of ASD were included in the ‘adults with ASD’ group. Edinburgh Handedness Inventory The Edinburgh Handedness Inventory (EHI; Oldfield, 1971) was administered to provide a scaled score of handedness. Adult participants were asked to score ten daily tasks on a five-point Likert scale based on which hand they preferred to use during each task (“Left hand strongly preferred” = 2, “Left hand preferred” = 1, “No preference” = 0, “Right hand preferred” = 1, or “Right hand strongly preferred” = 2). These tasks included daily activities such as writing, brushing teeth, and opening a box. The EHI was scored by combining the direction and exclusiveness of the hand preference. Two totals were created: one of right-hand preference and one of left-hand preference. The difference was then found by subtracting the left-hand total from the right-hand total. This was then divided by the total score of both hand preference scores and multiplied by 100 (i.e., 100 x (right-hand total – left-hand total) / (right-hand total + left-hand total)). Final EHI scores ranged from -100 to +100, with positive scores indicating right-handedness, and negative scores indicating left-handedness. Child participants were not required to complete the EHI questionnaire. Lexical Test for Advanced Learners of English A version of the Lexical Test for Advanced Learners of English (LexTALE; Lemhöfer & Broersma, 2012) was provided to assess the participants’ level of proficiency in English. Within this, adult participants were shown 60 written stimuli comprised of English words and pseudowords (words that follow the orthographical and phonetic rules of the English language and are pronounceable but are otherwise nonsense words, e.g. ‘proom’) and asked to assess whether each word was an existing English word or not. Scores of the test were collected by averaging the percentages of correct answers for English words and pseudowords, with final scores ranging from 0-100. Child participants were not required to complete the LexTALE task. Autism-Spectrum Quotient (Short Version) An abridged version of the Autism-Spectrum Quotient (AQ-Short; Hoekstra et al., 2011) was used to provide a measure of ASD traits. Participants with ASD were asked to rate 28 statements on a four-point Likert scale based on their level of agreement, with each answer accruing a different number of points (“Definitely agree” = 1, “Slightly agree” = 2, “Slightly disagree” = 3, or “Definitely disagree” = 4). On items in which “Definitely agree” represented a characteristic of ASD, the scoring was reversed. The scores for each question were totalled, with potential scores ranging between 28 (no ASD traits) to 112 (full inclusion of all ASD traits). Scores above 65 indicated ASD traits to a diagnosable degree. Neurotypical participants were not required to complete the AQ-Short questionnaire. Procedure Lateralisation for Facial Emotion Processing Task A chimeric faces task was used to assess lateralisation for facial emotion processing. Stimuli. The chimeric faces stimuli were created by Dr Michael Burt (Burt & Perrett, 1997) and provided by Parker et al. (2021). A collection of 16 different facial stimuli were created by merging two photographs of a man’s face depicting one of four emotions (‘happiness’, ‘sadness’, ‘anger’, or ‘disgust’) vertically down the centre of the face and blended at the midline (see Figure 1 for an example). Each emotion was paired either with itself, causing both hemifaces of the facial stimuli to match in emotion (a ‘same face’), or with a differing emotion, causing both hemifaces of the facial stimuli to be different (a ‘chimeric face’). Of the 16 stimuli, 12 were ‘chimeric face’ and four were ‘same face’. Task. Each trial began with a fixation cross shown for 1000ms, followed by the face stimuli for 400ms. Participants then recorded which emotion they saw most strongly by clicking the corresponding button from a choice of the four emotions (Figure 2). For the children, emoticons were used instead of written words (Oleszkiewicz et al., 2017) (Figure 3). A response triggered the beginning of the next trial, with a time-out duration set at 10400ms after which the next trial was triggered automatically. Response choice and response times were recorded. The task was split into four blocks of trials with a break between each block. Stimuli were presented in a random order and shown twice in each block, resulting in the participants being shown 32 stimuli per block and a total of 128 within the whole task. Participants were familiarised with the stimuli at the start of the task, with the ‘same face’ stimuli being shown alongside a label explaining which emotion was being presented, to ensure they could recognise the emotions. A practice block was given at the start of the task to ensure participants knew how to complete the task, using the emotions ‘surprise’ and ‘fear’. Additional Measures As data collection also included tasks for other studies, participants were also asked to complete a version of the Empathy Quotient – short (Wakabayashi et al., 2006), and undertake a dichotic listening task and its associated device checks (Parker et al., 2021). As these items were not part of the main study, participants were asked to complete these following the completion of the main study and its associated questionnaires and tasks, to ensure any findings from the study were not due to the additional measures. Laterality Index A laterality index (LI) for each participant was calculated using the same method as Parker et al. (2021) by finding the difference between the number of times the participant chose the right-hemiface emotion and the left-hemiface emotion. This was then divided by the total number of times they chose either the right- or left-hemiface emotion, and multiplied by 100 (i.e., 100 x (right hemiface – left hemiface) / (right hemiface + left hemiface)). Scores ranged between -100 and +100, with a negative LI indicating a left-hemiface bias, and thus, a right-hemispheric dominance, and a positive LI showing the opposite. Data Analysis Participants who scored less than 80 on the LexTALE task were removed as it was deemed their understanding of the English language was not strong enough and may cause issues with understanding the instructions (Parker et al., 2021). Furthermore, all trials with a response time faster than 200ms were removed as it was suggested that responses at this speed were too quick to have been based on the processing of the stimuli (Parker et al., 2021). In addition to this, outlier response times for each participant were removed using Hoaglin & Iglewicz's (1987) procedure. Within this, outliers were any response times 1.65 times the difference between the first and third quartiles, below the first quartile or above the third (e.g., below Q1 – (1.65 x (Q3-Q1)), and above Q3 + (1.65 x (Q3-Q1))). Following the removal of all outlying trials, any participant with less than 80% of trials remaining were removed. In addition to this, participants who scored less than 75% on ‘same face’ trials (trials in which both hemifaces depicted the same emotion) were noted, because emotion processing is an area of difficulty for individuals with ASD. Within this, three participants in the ‘children with ASD’ group (60%), three participants in the 'neurotypical children’ group (27.27%), four participants in the ‘adults with ASD group (13.33%), and 30 participants in the ‘neurotypical adults’ group (7.41%) scored less than 75% on ‘same face’ trials, suggesting they had difficulties identifying the emotions. To address the hypotheses, a linear model was performed using LI as the outcome and group (‘ASD’ or ‘neurotypical’), age (‘adult’ or ‘child’) and emotion (‘happy’ and ‘angry’, or ‘sad’ and ‘disgust’) as the predictors, including interactions between each predictor (Group x Age; Group x Emotion; Age x Emotion; and a three-way interaction, Group x Age x Emotion).
Comparison of Ethical Decision-Making in Emergency Service Workers and Laypeople
Trolley Problem, ethical dilemmas, time pressure, emergency service workers, decision-making.
The Trolley Problem is a theoretical ethical dilemma in which it is asked whether it is morally acceptable to actively kill one person to save five (Thomson, 1976). Emergency service workers (ESW) are often presented with ethical dilemmas, such as whether to resuscitate someone who does not want to be resuscitated (Guru et al., 1999). The present study investigated the differences in decisions made when faced with variations of the Trolley Problem between laypeople (non-ESW) and ESW. The effect of time pressure on making these decisions was also investigated, measured through response time. 99 participants were tested, 47 laypeople and 52 ESW. Participants were presented with five different Trolley Problem dilemmas wherein they could passively allow five people to die, or to make an active decision to sacrifice one person to save the others. These dilemmas had distinct variations, such as the one person being a co-worker, or where participants had to physically push and kill a large man. Half the participants were placed into a time pressure condition, and were told that they had a time limit in which to respond, when no time limit existed. Results showed that neither occupation nor time pressure significantly affected response time or participant choice. Further analysis suggested some interaction effects between occupation, time pressure, and specific dilemma types. Implications such as suggested training practices for ESW will be discussed. Criticisms of the methodology and recommendations for future research will also be discussed.
Method Sample This project aimed to use a total of 112 participants, with 56 of these being ESW, and 56 being laypeople. This number was calculated using the G*Power software, using an alpha of .05, power of .8, and a medium expected effect size of .35, using five levels of measurement. In total, 99 participants were gathered for the present study. 47 of the sample were laypeople, whilst the other 52 were ESW. Of these, 22 were police officers, and 30 were ambulance crewmembers. Overall, ESW had an average of 7.7 years of experience (SD = 8.29), with ambulance staff having an average of 10.14 years (SD = 9.89), and police having an average of 4.52 years (SD = 4.17). Unfortunately, no other emergency service branches such as coast guard or firefighters completed the study. A gender split of 47 males to 48 females was gathered, along with an average age of 35.65 years old (SD = 12.98). Three participants declined to disclose their gender, and one participant identified as agender. Ethical Approval and Pre-Registration This study gained ethical approval on 13/04/2021, from members of the Psychology department at Lancaster University. This study was also pre-registered on the Open Science Frameworks website on 17/05/2021. This can be found at the following link: https://osf.io/4ecjg/?view_only=95615bd16f2c4a9db88dd77543780ec2 Materials Survey The present study was delivered through a Qualtrics survey file, created fully by the researcher. The survey contains standard psychological research documents, such as an information page, consent form, demographic information page, and debriefing. The survey also contains two sets of five vignettes describing ethical dilemmas for each condition of the experiment. Demographics Participants are asked to provide some demographic information: age, gender, and occupation. Participants are given options for occupation, including police, fire, or ambulance, as well as an option for ‘other’ emergency services, where a free typing box is presented. This is to cover occupations outside of the main three emergency services, such as coastguard or mountain rescue. If participants are not ESW, they have the option to say they are not a member of the emergency services. Ethical Dilemmas The present study tests a set of five ethical dilemma vignettes. To read each dilemma, see Appendix A. Each vignette describes a version of the Trolley Problem, where there is an out-of-control trolley (the word “tram” is used to make it clearer to British participants) speeding down the tracks towards a group of five people. For each dilemma, there is an active choice, or a passive choice, which entails sacrificing one life to save five, or allowing five people to die to avoid killing one person. Each dilemma presents a different single person who could be placed in danger, these are: a non-descript person, an elderly person, a co-worker, a large man, and the “culprit”. Non-Descript Person. This dilemma is a traditional retelling of the Trolley Problem. Participants are told that there is an out-of-control trolley speeding down the tracks, towards five people who are stranded. Participants are told that they have the choice to pull a lever and divert the trolley onto a different track, however there is one person stranded on those tracks. The decision participants are faced with here is whether to make an active choice or a passive choice. The active choice is to pull the lever, diverting the trolley and saving the five, whilst sacrificing the individual. The passive choice is to not pull the lever, allowing the trolley to hit the five people, whilst saving the individual. It is often found that people sacrifice one person to save five in this dilemma (Thomson, 1976; Greene, 2016). Responses to this condition demonstrate how people weigh up lives on a strictly numerical basis, knowing nothing about the traits of the person. By having a condition in which participants know nothing about the person on the tracks, this can be compared to responses when it is an elderly person or a co-worker on the tracks. Elderly Person. This dilemma is the same as the non-descript person dilemma, however participants are told that the person on the tracks is elderly. This condition has been found to affect how people respond to the Trolley Problem, with people being more likely to sacrifice the elderly person over any other ages (Kawai et al., 2014). This is interesting in the study of moral psychology, as it shows how people weigh up the worth of lives based on certain attributes, such as age. This can also be compared to how people respond when they know nothing about the person on the tracks. This is also important to investigate in an ESW context, as elderly people are more likely to be admitted to hospital (Burns, 2001), leading ambulance crews to encounter them more often. Co-Worker. This dilemma is the same as the non-descript person dilemma, however participants are told that the person on the tracks is one of their co-workers. This dilemma was chosen based on past research suggesting that participants are less likely to sacrifice people they perceive to be part of their identity in-group (Swann Jr et al., 2010). This is a relevant factor to investigate as part of a study into ESW, a group who develop strong in-group feelings, including having better self-care and social support (Shakespeare-Finch et al., 2002). This is also interesting when investigating ESW populations such as firefighters or police, who may be placed into situations where a co-worker is in danger whilst trying to save members of the public. This dilemma demonstrates how ESW weigh up the lives of their co-workers compared to strangers. Large Man. In this dilemma, participants are told that there are five people on the tracks, and stood next to them is a large man. Participants are told that if they push the large man into the tracks, that would stop the trolley and the five people would be saved. The decision participants are faced with here is whether to make an active choice and push the large man onto the tracks, stopping the trolley and saving the five, or to make a passive choice and allow the trolley to hit the five people. This is a version of the “Footbridge Dilemma”, in which it is found participants are typically less willing to make the active decision and push the man (Nichols & Mallon, 2006). It is an interesting take on the Trolley Problem dilemma, as it forces participants to make a more physical decision through pushing and directly causing a person’s death, as opposed to pulling a switch which then indirectly leads to someone’s death. This is also relevant in the study of ESW, who tend to work directly and physically with people as opposed to making indirect decisions. Culprit. This dilemma is the same as the Large Man dilemma, however rather than a large man, participants are told that stood next to them is the “culprit”. The “culprit” is explained to participants as the person who stranded the other five people on the tracks. This dilemma was chosen as it tests how people respond to the same physical pushing decision as the Large Man condition, however when the person they can push is not an innocent bystander, and instead is someone who is trying to end the lives of others. This allows for the investigation of how people weigh the lives of criminals compared to innocent people. This is also interesting in the study of ESW, especially when regarding police, since their occupation involves apprehending criminals so they can then be sentenced, not choosing the punishment based on their own moral reasoning. Time Pressure Participants who are assigned to the Time Pressure condition are told both during instructions and above each dilemma that they only have a limited amount of time to make their decision. They are told that after that time has passed, they may not be able to provide a response. This is not true, there are no time limits on any question. This is to attempt to simulate time pressure, by making participants feel they have limited time to react. Overall, 52 participants were assigned to the Time Pressure condition, and 47 were assigned to No Time Pressure. A more equal split was aimed for, however was not possible due to the number of incomplete responses interfering with the equal randomisation of conditions. Response Time The decision-making speed is automatically recorded by Qualtrics, determining how long it took participants to finalise their decision. This is taken as the time from when participants opened a vignette, until they submitted their response. It was decided that the response time would be taken at the point the choice is submitted, as opposed to the last button press participants made. This is as it cannot be certain at what point participants have finished considering their response. They may still be thinking about their answer after selecting the option, but before submitting. Therefore, it cannot be assumed that the final button press was the end of their decision-making. Justification After each decision, participants are asked to briefly explain why they made the decision they did, imagining they are speaking to a close friend. This ensures participants think deeper into the decision they make, as they know they will have to defend it. This is presented to participants as a free entry text box, shown after each dilemma they respond to. Pilot Study The present study was first piloted on an ESW member, in this case a senior paramedic, to test for validity of the ethical dilemmas as well as any other issues with the survey. The only negative feedback received was that some of the dilemmas looked visually similar on the page, and could be mistaken for being the same as the dilemma before. To resolve this, a section reminding participants to read carefully since every dilemma was different was added, as well as formatting changes such as boldening the critical sections of text to make them more obviously different. Procedure Participants were recruited via social media, ESW were gathered via the Our Blue Light ESW charity’s social media pages, as well as being sent around stations via the researcher’s contacts. Laypeople were also gathered through social media, with some being recruited from the Our Blue Light pages, as well as through friends and family of the researcher. Participants had access to the study through a link, which took them to the introduction page of the present study. After reading this and giving consent, the study began. Participants were randomly assigned by the Qualtrics software to either the Time Pressure or No Time Pressure condition. This affected which set of instructions they saw. Participants were all shown each of the five dilemmas, presented one by one on their screen. The dilemmas were presented in a randomised order for each participant, to avoid any order effects. Following each dilemma, participants were presented with the justification question and free entry text box. After repeating this for each dilemma, participants were presented with a debrief page, and the study concluded. Data Analysis To examine the choices ESW made compared to laypeople, a 2x2 chi square test will be conducted. A 2x2 chi square test will also be conducted to examine the choices made by those in the time pressure condition against those who were not. Descriptive statistics will also be presented, including the counts of each choice made separated into groups, along with means and standard deviations of response time. In order to analyse the impact of Occupation, Time Pressure, and Type of Ethical Dilemma on the decisions participants make, a generalised linear mixed-effects model will be used (Baayen et al., 2008). The statistical family used for this model will be binomial. This test was chosen as the dependent variable here, participant choice, is a categorical variable with two options (push or no push). There are also three categorical independent variables, two of which are between-subjects factors (ESW v Layperson, Time Pressure v No Time Pressure), and one within-subjects factor (Type of Ethical Dilemma). The only random effect to be used in the model is individual subjects, as each independent variable is critical to the present study, and so will be treated as fixed effects. To compare the response time between ESW and laypeople, as well as time pressured participants and participants with no time pressure, two one-way ANOVAs will be conducted. This was chosen as the intention here is to compare performance between two independent groups. A 2x2 ANOVA on sum scores was considered, however was not possible due to participants having simultaneous membership of two groups (e.g. ESW + Time Pressure, ESW + No time pressure). To further analyse participant response times to the ethical dilemmas, a 2x2x5 Mixed ANOVA will be conducted. This was chosen as the method of analysis as one aim of the present study is to compare variance between ESW and laypeople, as well as participants being under time pressure or not. There is also the factor of ethical dilemma, which has five levels due to there being five different dilemmas.
Main Data_35645845/Excel.csv , 35645845 Occupation Response Time Sum Scores/Excel.csv , 35645845 Time Pressure Response Time Sum Scores/Excel.csv, 35645845_RStudio Code/RStudio.R
Competence and Warmth: How Gender Impacts Perceptions of Male and Female Speakers.
gender stereotypes competence, warmth stereotype content model
Using the stereotype content model as a theoretical background, this study aimed to investigate the relationship between gender stereotypes and judgements of warmth and competence. Visual appearance has long been used to research these judgements while auditory cues have often been overlooked. This study therefore focused on judgements made about voice and subsequently did not influence participants with predetermined gender labels. 61 participants – aged 19 to 60 – listened to either 2 male or 2 female speakers talk about domestic violence and cancer research. Domestic violence is here defined as a women-centric topic, while cancer research is considered gender neutral. Participants completed person perception inventories of each speaker, rating them on 7-point Likert scales in terms of 10 competence and 10 warmth items. They also completed a sexism inventory to determine whether sexism predicted a more favourable attitude toward male speakers. A 2 between gender (male vs female) by 2 within topic (domestic violence vs cancer research) ANOVA was conducted, and female speakers were judged as more competent than males when speaking on domestic violence but not cancer research. They were considered warmer than men in both cases. This indicates that women are seen as competent when speaking on issues that directly affect them, suggesting that they should be taken more seriously when speaking out about their own rights. However, traditional warmth stereotypes regarding women were upheld. This, along with further implications, are discussed.
Items. 10 competence items and 10 warmth items were selected to compile a 20-item list of characteristics for participants to judge speakers on. Of these items, 11 were taken from Rudman & Glick (1999) and the remaining 9 were considered in the original SCM. Items used in the competence and warmth scales were found to be reliable across speech topics, namely cancer research (CR) and domestic violence (DV) (competenceCR α = .893, competenceDV α = .931). This indicates that the scales used were highly reliable. Similarly, for the warmth dimensions, Cronbach's Alpha was suitably high (WarmthCR α = .918, WarmthDV α = .944). The reliability for the sexism inventory was also acceptable, with an α value of .826. An example of several competence and warmth dimensions can be seen below, while a full list can be found in Appendix A. Competence: confident, ambitious, intelligent.. Warmth: trustworthy, likeable, supportive. Speeches. Two speeches were recorded for the purpose of the experiment, one focused on domestic violence and the other on cancer research. The speeches were written to closely match each other in terms of wording and the information being presented. For instance, the opening and closing sentences of each speech were similarly structured, as seen below. Table 1. Examples of speech text. Domestic Violence Cancer Research Opening sentence Domestic Violence. A topic that is often glossed over as something that effects other people - not me; not you. Cancer. A topic we don't often like to think about – something that effects other people, but not me: not you. Closing sentence By going to our website www.dvrefuges.co.uk you can find out more information about the great work women's refuges around the country do, and help them continue to change women's lives by donating to our cause. By going to our website www.ukcancer.co.uk you can find out more information about the great work that we do, and by donating to our cause, help us continue to help people diagnosed with cancer live a normal life. The details of the speeches differed, and the content was varied enough so as not to be obviously the same to participants, but the speeches were largely similar, as can be seen in Appendix B. Four speakers were responsible for recording the two speeches, a male and female speaker for each topic. This allowed participants to hear both speeches either spoken by two male or two female speakers. All four speakers were from the same region and had northern accents, however, two speakers' accents differed slightly from the remaining two, which may have been particularly noticeable to northern participants. To account for this, one speaker with each accent was assigned to each topic condition and so any accent effects were counterbalanced and can be assumed to not have influenced judgements. Speeches were recorded using an iPhone 6 microphone and edited using Audacity in order to eliminate background noise and static. Recordings were then given a plain video image of a black background with text reading either 'Recording One' or 'Recording Two' respectively. Due to the fact that recordings were counterbalanced across conditions, all four recordings were presented either as first or second in at least one condition, so in total 8 versions of the recordings were made and embedded into Qualtrics, where the body of the survey was hosted. Participants listened to recordings using Sony headphones during the experiment. Procedure Participants were assigned to one of four conditions. In each condition they were asked to listen to the first speech, either domestic violence or cancer research, spoken by either a male or female speaker. After listening to the speech, they proceeded to the next online page and completed the speaker evaluation, rating the speaker on the 20 warmth and competence dimensions. This was indicated by how well they believed each item fit the speaker by choosing a point on a 7-point Likert scale (1 = completely disagree, 7 = completely agree). Following this they listened to the second speech spoken by a different speaker of the same gender. They then completed the same speaker evaluation for the second speaker. Finally, they completed the sexism inventory (The Ambivalent Sexism Inventory, Glick & Fiske, 1996) which measured the participants' explicit sexist attitudes on a 5-point Likert scale (1 = strongly agree, 5 = strongly disagree). A copy of the items in this inventory can be found in Appendix C. As this was a 2 (gender: female vs. male) x 2 (topic: domestic violence vs. cancer research) experimental design with repeated measures on the second factor, the difference between each condition was purely the order in which the speeches were presented (domestic violence first or second) and the gender of speaker that each participant heard (male or female) for the purpose of counterbalancing. So as not to influence participants to respond in a set way, the experiment was presented as regarding the evaluation of speakers and not as explicitly about gender. Following the main section of the experiment, participants were asked a number of questions regarding how they experienced the recording, the first of which was answered on a 5-point scale (1 = strongly agree, 5 = strongly disagree). The question was: 'how likely are you to visit the website mentioned in this speech.' This was relevant in order to measure whether the competence of the speaker affected the likelihood of the participant to engage with the issue. Importantly, participants were also asked whether they considered each topic to be masculine or feminine, again measured on a 7-point scale (1 = feminine, 4 = neither feminine nor masculine, 7 = masculine). This was included in order to provide validity to the assumption that the domestic violence topic would indeed be judged as more women-centric, and the cancer research topic would be neutral. It is therefore of note that over 50% of participants considered domestic violence to be a feminine topic, others considered it gender neutral, but very few considered it a masculine topic. The majority of participants judged cancer research as gender neutral, as was intended. Finally, participants were asked whether or not they had any experience of the topic at hand, either personally or from a friend or family member, as this may have caused them to make more favourable judgements towards the topic they were more invested in. Participants also gave their gender, nationality and age. Gender and nationality were exploratory variables of particular interest due to the belief that other women may be more likely than men to evaluate women as competent. Nationality was of interest due to the fact that people from other cultures, particularly Eastern cultures, have different gender roles than we do in the UK, and so their responses during the experiment may have reflected this. Once the experiment was complete participants were fully debriefed and had the chance to enter a competition to win a prize in return for their participation.
Contrast polarity of a stimulus does not affect the cueing effect
Gaze cueing Contrast polarity Gaze perception
According to the contrast polarity effect, people’s attention is sensitive to dark objects within light backgrounds. According to the gaze-cueing effect, a human gaze shift attracts people’s attention towards the direction of the darker region of the observed eyes, thus the gaze-cueing effect depends on the contrast polarity of the observed eyes. Therefore, a human gaze is perceived as a darker spot within a lighter background. In the present study, combining the contrast polarity effect and the gaze-cueing effect we examined whether the colour contrast between a black and a white square that suddenly flip on a computer screen can have a similar effect to that of gaze-cueing. The prediction was that participants would perceive the side where the black square moved after the flipping as attentional cue, therefore when an object appeared on the side that the black square moved, reaction times would be shorter compared to when the object appeared on the opposite side. The results showed that reaction times in the two conditions did not differ significantly. Thus, the contrast polarity of a stimulus does not affect the cueing effect.
The experiment was conducted using a single within-subject design. The independent variable was the cue congruency, which consisted of two conditions: the object appeared either congruently or incongruently with the attentional cue. The dependent variable was the reaction times of the participants which were measured in millisecond (ms). Procedure. Each participant was tested individually in a quiet room at the library of Lancaster University. Participants were tested at different days and times, including morning and evening hours. The only people present in the room during the conduct of the experiment were the participant and the experimenter. In the beginning, participants were asked to read the experiment instructions from the computer screen and they were also given clarifications, if needed, by the researcher. Afterwards, the experiment started and two squares, one black and one white, sharing one side were presented on the screen for half a second. The side that the squares shared was located at the centre of the screen, therefore one square appeared on the left side of the screen and the other one on the right side of the screen. Then the squares flipped and changed position and the apparent motion of the two squares was the cue. One second after flipping, the squares disappeared and a picture of an object randomly appeared either on the left or on the right side of the screen for one more second. Afterwards, the object disappeared and the screen remained blank. The task of the participants was to press the appropriate keyboard button as fast and as accurately as possible, depending on the side of the screen where the object appeared. So, they had to press the «Q» button on the keyboard when the object appeared on the left side of the screen or the «P» button when the object appeared on the right side of the screen. They were given one second to respond to the object appearance. The sequence of the trials was the same for every participant. Each one of the 6 objects appeared on total 30 times congruently with the cue and 30 times incongruently with it. Thus, the total number of trials for every participant was 360, 180 trials that the objects appeared congruently with the cue and 180 that they appeared incongruently with it. The experiment lasted for 20 minutes for each participant and at the end of every session, a message appeared on the screen which informed the participants that the experiment was over. The prediction was that the side where the black square would move after the flipping would be perceived as an attentional cue by the participants. Their gaze would be attracted to the cue and an effect similar to the gaze-cueing effect would appear. So, their reaction times would be shorter for the trials where the objects would appear on the same side with the attentional cue compared to the trials where the objects would appear on the opposite side of the cue. The independent variable was the cue congruency which included two conditions, the congruent trials (when the object appeared on the same side with the cue) and the incongruent trials (when the object appeared on the opposite side of the cue).
Cortical Hyper Excitability correlating with Visual Distortions and Hallucinations
visual distortions cortical hyper excitability Pattern Glare Task
Background: The primary focus of our study is how the abnormalities in the visual experiences such as the visual distortions or hallucinations result in the increase in the cortical hyper excitability. The aberrant neural activity causes visual distortions. Susceptibility to such visual distortions reflects elevated levels of cortical hyper excitability. Methods: Forty-eight individuals completed the "Pattern Glare Task" (where they viewed certain striped grating patterns with different spatial frequencies). Participants also completed the Cortical Hyperexcitability Index (Chi) and the Cambridge Depersonalization Scale (CDS). Results: Pattern glare task showed that individuals experienced more visual distortions in the Medium Frequency (3 cpd). A very small sample of the population showed effects of depersonalisation disorder. Based on our results, we can say that individuals did show an elevated level of cortical hyperexcitability. Conclusion: The study suggests that non-clinical population also experiences a certain level of increase in cortical hyper excitability. It only establishes the utility of pattern glare with regards to CHi and CDS to add to our existing knowledge.
Pattern Glare Test The pattern glare task includes stripy patterns on three separate cards each with different spatial frequencies; low spatial frequency baseline grating (approx. 0.5 cycles per degree), high spatial frequency baseline grating (approx. 12 cpd), and the crucial medium spatial frequency grating (approx. 3 cpd). The computerised version of the pattern glare task was modified for this experiment, as we were using a paper-based version (Wilkins, 1995; Wilkins et al., 1984) for the same. The stimuli used in the experiment are given in FIGURE 1. The individuals are asked to stare at the white dot in the center of each pattern for approximately 10-15 seconds, while holding each pattern at arm's length. Following, a series of questions are asked to the participant i.e. if they experienced any blurring of lines, bending of lines, fading, shimmering, flickering or shadowy shapes. The participants on the basis of their experience on viewing each pattern, rate the above questions from a score of 0-7 where, 0-minimum and 7-maximum (Wilkins et al., 1984; Conlon et al., 1999). The score is obtained for each pattern and the difference between Pattern 2 and Pattern 3 is recorded, which is called as the '3-12 difference'; in other words, the difference between high frequency and the medium frequency (3cpd – 12cpd). Cambridge Depersonalisation Scale The CDS is a self-reporting questionnaire and is used to measure the duration and frequency of any depersonalisation symptoms that individual experiences in the time frame of the past six months. (Sierra and Berrios, 1999). The CDS is an instrument containing 29 items. Each of the items in the scale are rated on the basis of Likert-scale both for frequency (0-4; where, 0=never, 1=rarely, 2=often, 3=very often, and 4=all the time) and duration based on its average on how much the experiences last (1-6; where 1=few seconds, 2=few minutes, 3=few hours, 4=about a day, 5=more than a day, and 6=more than a week). Its global score is the sum of all items (0-290). Sierra et al., (2005) established four well determined factors to dictate the different symptoms of depersonalisation as single or underlying dimensions they were, ‘Anomalous Body Experience’, ‘Emotional Numbing’, ‘Anomalous Subjective Recall’, and ‘Alienation from Surroundings.’ This questionnaire addresses the complexity of depersonalisation and uncovers its symptoms, which can be directed towards distinct psychopathological domains. Cortical Hyperexcitability Index The CHi was designed to provide an index that discovers the visual irritability, discomfort and the associated visual distortions that individual’s experience (Braithwaite, Merchant, Dewe and Takahashi, 2015). The above-mentioned experiences are well linked to the increase of cortical hyperexcitability. A major advantage of the CHi’s design is that it unveils three broad factors which are (1) heightened visual sensitivity and discomfort, (2) negative aura-type visual aberrations, and (3) positive aura-type visual aberrations. The items present in the questionnaire picture a vast selection of visual experiences that have been previously reported through hallucinations based experimental studies on patients, control groups, non-clinical populations; aura and its underlying dimensions. The CHi uses a fine-grained 7-point Likert response scales, where in the test each question has two response scales i.e. frequency (1-7; where 1=not at all frequent and 7=very frequent) and intensity (1-7; where 1=not at all intense and 7=extremely intense). In terms of scoring, both the scales are summed to provide an overall CHi index for each question. However, a value of 1 is subtracted from each response on frequency and intensity, as the scale was transformed from 1-7 to a 0-6 Likert-scale. This was done for individuals who responded with 1 in every question would still have a score of 54. Design and Procedure All the participants were forwarded a brief explanation about the purpose of the study and how they can contribute to it. If the participants agree, later schedule a time for the voluntary study. The experiment was conducted in the Social Hub of the Graduate College, Lancaster University. The participants were seated comfortably on the right side of the researcher. The individuals were asked to read the Participant Information sheet carefully, later if they agree; they may sign their respective consent form. It was made clear to the participants that the confidentiality of their personal information will be ensured and that they could at any point (1) can ask questions during the experiment, (2) stop the experiment, if they are uncomfortable at any point during the conduction (3) participants have the right to withdraw themselves from the study with no further adverse consequences however, they need to inform the researcher about this via email. Participants were again asked if they suffered from any neurological disorder specially migraine, migraine (aura), or photo sensory epilepsy and if they had any severe incidences of alcohol and drug abuse. The first phase of the experiment included the pattern glare task. Individuals were handed over with the first pattern with low frequency (LF) and were asked to stare at the white dot in the centre of the pattern for 10-15 seconds. After this, they were asked to rate the questions based on their experience on a scale of 0-7 (0-minimun, 7-maximum). The questions included if they experienced any blurring of lines, bending of lines, shimmering or flickering, fading or if they could see any shadowy shapes. Before handing over the second pattern, it was made sure that the participant is comfortable with proceeding further with the experiment and is not experiencing any kind of visual stress. The same steps were repeated for both the other two patterns with medium frequency (MF) and high frequency (HF). The order in which the participants viewed the patterns was randomised for each one of them. Individuals who are prone to pattern glare can be quantified for such a criterion based on their sum of distortions in 3cpd (MF) or as the difference between 3 and 12 cpd, also called the '3-12 cpd difference'. After a two-minute break, the second phase of the experiment included participants to answer 29 questions on the Cambridge Depersonalisation Scale, which are based on the frequency and duration of any 'strange or funny experiences' that they felt in the past six months. Lastly, the third phase, the second questionnaire was introduced to the participants. The Cortical Hyper Excitability Index. Similar to the patterns, the questionnaires presented to the participants were also randomised in order to obtain a variety in the responses of the participants. The total time taken to conduct the experiment was about 20 minutes or less. Post conduction the individuals were thanked for their time and effort.
The primary focus of our study concerned how abnormalities in visual experiences such as visual distortions or hallucinations result in increase in cortical hyper-excitability in the non-clinical population. Aberrant neural processes leads to anomalous experiences. Susceptibility to such visual distortions reflects elevated levels of cortical hyper excitability. On the account of methodology, Forty-eight non-clinical individuals completed the "Pattern Glare Task" where they viewed certain striped grating patterns with different spatial frequencies. The non-clinical participants also completed the Cortical Hyper-excitability Index (Chi) and the Cambridge Depersonalization Scale (CDS). From the analysis, Pattern glare task performance showed that individuals experienced more visual distortions in the Medium Frequency (3cpd). The CDS and Chi results only confirm our study further. Conclusively, the study suggests that members of the non-clinical population do experience a certain level of increase in cortical hyper-excitability. It establishes the utility of pattern glare with regards to CHi and CDS to add to our existing knowledge.
Introduction The major objective of this study is to understand the relationship between the cortical hyper-excitability and the various visual hallucinations or distortions in the non-clinical population. The major research question is to understand how the aberrant neural processes lead to anomalous experiences. This section investigates into the methodology that has been used to investigate and validate hypotheses postulated by the research question of this project. The participants for this study are 48 non-clinical constituents. These participants were tested with the Pattern Glare Task, the Cortical Hyper-Excitability Index and the Cambridge Depersonalization Scale. Participants Forty-eight numbers of individuals, undergraduates and postgraduates ageing between 21 and 33 from were recruited for the experiment via random sampling. The mean age of the participants was 24. Out of these, 30 (62%) were male participants while 18 (38 %) were the number of female participants. None of the individuals reported any medical history of seizures, photo sensory epilepsy or were diagnosed with migraine. Individuals suffering from migraine, migraine (aura) or photosensitive epilepsy were excluded from the study. Materials Pattern Glare Test The pattern glare task includes stripy patterns on three separate cards each with different spatial frequencies; low spatial frequency baseline grating (approx. 0.5 cycles per degree), high spatial frequency baseline grating (approx. 12 cpd), and the crucial medium spatial frequency grating (approx. 3 cpd). The computerised version of the pattern glare task was modified for this experiment, as we were using a paper-based version (Wilkins, 1995; Wilkins et al., 1984) for the same. The stimuli used in the experiment are given in Figure 1. The individuals are asked to stare at the white dot in the center of each pattern for approximately 10-15 seconds, while holding each pattern at arm's length. Following, a series of questions are asked to the participant i.e. if they experienced any blurring of lines, bending of lines, and fading, shimmering, flickering or shadowy shapes. The participants on the basis of their experience on viewing each pattern, rate the above questions from a score of 0-7 where, 0-minimum and 7-maximum (Wilkins et al., 1984; Conlon et al., 1999). The score is obtained for each pattern and the difference between Pattern 2 and Pattern 3 is recorded, which is called as the '3-12 difference'; in other words, the difference between high frequency and the medium frequency (3cpd – 12cpd). Cambridge Depersonalization Scale The CDS is a self-reporting questionnaire and is used to measure the duration and frequency of any depersonalization symptoms that individual experiences in the time frame of the past six months (Sierra and Berrios, 1999). The CDS is an instrument containing 29 items. Each of the items in the scale are rated on the basis of Likert-scale both for frequency (0-4; where, 0=never, 1=rarely, 2=often, 3=very often, and 4=all the time) and duration based on its average on how much the experiences last (1-6; where 1=few seconds, 2=few minutes, 3=few hours, 4=about a day, 5=more than a day, and 6=more than a week). Its global score is the sum of all items (0-290). Sierra et al., (2005) established four well determined factors to dictate the different symptoms of depersonalization as single or underlying dimensions they were ‘Anomalous Body Experience’, ‘Emotional Numbing’, ‘Anomalous Subjective Recall’, and ‘Alienation from Surroundings.’ This questionnaire addresses the complexity of depersonalization and uncovers its symptoms, which can be directed towards distinct psychopathological domains. Cortical Hyper excitability Index The CHi was designed to provide an index that discovers the visual irritability, discomfort and the associated visual distortions that individual’s experience (Braithwaite, Merchant, Dewe and Takahashi, 2015). The above-mentioned experiences are well linked to the increase of cortical hyper excitability. A major advantage of the CHi’s design is that it unveils three broad factors which are (1) heightened visual sensitivity and discomfort, (2) negative aura-type visual aberrations, and (3) positive aura-type visual aberrations. The items present in the questionnaire picture a vast selection of visual experiences (sensitive to external sensory information for e.g. lights, patterns; certain environment is uncomfortable for the individual; dizziness/nausea; discomfort/ irritation from reading a certain font or style of writing etc) that have been previously reported through hallucinations based experimental studies on patients, control groups, non-clinical populations; aura and its underlying dimensions. The CHi uses a fine-grained 7-point Likert response scales, where in the test each question has two response scales i.e. frequency (1-7; where 1=not at all frequent and 7=very frequent) and intensity (1-7; where 1=not at all intense and 7=extremely intense). In terms of scoring, both the scales are summed to provide an overall CHi index for each question. However, a value of 1 is subtracted from each response on frequency and intensity, as the scale was transformed from 1-7 to a 0-6 Likert-scale. This was done for individuals who responded with 1 in every question would still have a score of 54. Design and Procedure All the participants were forwarded a brief explanation about the purpose of the study and how they can contribute to it. If the participants agree, later schedule a time for the voluntary study. The experiment was conducted in the Social Hub of the Graduate College, Lancaster University. The participants were seated comfortably on the right side of the researcher. The individuals were asked to read the Participant Information sheet carefully, later if they agree; they may sign their respective consent form. It was made clear to the participants that the confidentiality of their personal information will be ensured and that they could at any point (1) can ask questions during the experiment, (2) stop the experiment, if they are uncomfortable at any point during the conduction (3) participants have the right to withdraw themselves from the study with no further adverse consequences however, they need to inform the researcher about this via email. Participants were again asked if they suffered from any neurological disorder specially migraine, migraine (aura), or photo sensory epilepsy and if they had any severe incidences of alcohol and drug abuse. The first phase of the experiment included the pattern glare task. Individuals were handed over with the first pattern with low frequency (LF) and were asked to stare at the white dot in the center of the pattern for 10-15 seconds. After this, they were asked to rate the questions based on their experience on a scale of 0-7 (0-minimun, 7-maximum). The questions included if they experienced any blurring of lines, bending of lines, shimmering or flickering, fading or if they could see any shadowy shapes. Before handing over the second pattern, it was made sure that the participant is comfortable with proceeding further with the experiment and is not experiencing any kind of visual stress. The same steps were repeated for both the other two patterns with medium frequency (MF) and high frequency (HF). The order in which the participants viewed the patterns was randomized for each one. Individuals who are prone to pattern glare can be quantified for such a criterion based on their sum of distortions in 3cpd (MF) or as the difference between 3 and 12 cpd, also called the '3-12 cpd difference'. After a two-minute break, the second phase of the experiment included participants to answer 29 questions on the Cambridge Depersonalisation Scale, which are based on the frequency and duration of any 'strange or funny experiences' that they felt in the past six months. Lastly, the third phase, the second questionnaire was introduced to the participants, the Cortical Hyper Excitability Index. Similar to the patterns, the questionnaires presented to the participants were also randomised in order to obtain a variety in the responses of the participants. The total time taken to conduct the experiment was about 20 minutes or less. Post conduction, the individuals were thanked for their time and effort.
Could eye movements provide a window into early signs of dementia? Investigating the relationship between eye movements and cognitive decline.
Past research has indicated a relationship between eye movement abilities and cognitive decline. Specifically, performances on the anti-saccade task and pro-saccade task have demonstrated a correlation with Alzheimer’s disease (AD) severity, suggesting that impairments in visual ability may be a potential biomarker for dementia. However, little research has investigated whether the same deficiency is present in more ecologically valid tasks. The current study therefore aimed to extend the dementia literature by examining eye movement abilities in individuals with AD when completing a task that required the visual exploration of videos. In order to investigate a disease effect, patients with AD were compared to healthy older controls. To explore age effects, the older controls were additionally compared to healthy younger controls. To attempt to replicate previous findings, all groups first completed both the pro-saccade and anti-saccade task, before subsequently completing a video task designed to require similar abilities as those necessitated by the anti-saccade task. The findings revealed clear qualitative differences between the age effect and the disease effect on the anti-saccade task, suggesting that AD is not purely an accelerated form of ageing. Furthermore, the results supported the contemporary literature, in that, patients with AD made more errors, and less corrected errors, on the anti-saccade task. In turn, these results advocate for the utilisation of the task as a biomarker of AD. However, this impairment did not translate to the videos task. These results suggest that certain conditions may be conducive to normal viewing behaviour in patients with AD, and thus may potentially indicate that the natural exploration of videos is not a reliable biomarker for AD.
For all saccade tasks, a repeated measures design was used, with group as the independent variable (AD, OC, and YC). For the PST there were 2 dependent variables: latency and amplitude (see appendix A for definitions). For the AST there were 5 dependent variables latency, amplitude, number of errors, corrected errors percentage, and corrected errors start time (see appendix B for definitions). For the videos a 3(Group: AD, OC, YC) x 2(Instructions: free view, instructed view) mixed design was used, with group as a between-subjects factor and instructions as a within-subjects factor. For each of the videos, dwell time was calculated as the dependent variable. A total of 25 AD, 17 OC and 37 YC completed the video task. Materials Eye tracking apparatus. An EyeLink Desktop 1000 eye-tracker was used at 1000Hz to record eye movements. Participants sat approximately 55cm away from the screen with their head on a chin rest to minimise movement. A 3x3 grid of sequentially appearing dots was used to calibrate participant’s dominant eye with the machine. Pro-saccade task. The PST provides a measure of involuntary responses to visual stimulus. The methods utilised in this study followed previously established procedures (Crawford et al., 2005). In order to centre the participant’s gaze, the trial commenced displaying a central fixation target for 1000 milliseconds. This target then disappeared for 200 milliseconds, before a peripheral target appeared for 2000 milliseconds either to the left or right of the initial central fixation target (at ± 4°). The direction was randomised in order to avoid predictive saccades. The inter-trial interval then took place for 1200 milliseconds. The next trial began when the central fixation point reappeared. The participant’s task was to look at the peripheral target as quickly and accurately as possible (see appendix C). There were 36 trials in total. Anti-saccade task. The AST provides a measure of inhibition. The task format was identical to the PST except here the participants were instructed to look as quickly as possible to the area, equidistant, but in the opposite direction to the peripheral target (mirror image) (see appendix D). There were 24 test trials in total and 4 practice trials. Video task. The video task required participants to watch four, 40 seconds long videos. Three of the videos were viewed three times by participants and consisted of clips from past events in history: the coronation of Queen Elizabeth II, Neil Armstrong landing on the moon, and Gordon Brown and his family leaving Downing Street after losing the general election. Prior to each viewing of the video, participants were given different instructions relating to the video. On first viewing participants were instructed to freely watch the video, this was in order to elicit a bottom-up control of eye gaze to highly salient objects. On second viewing participants were asked questions relating to non-salient objects in order to elicit a top-down control of eye gaze. The fourth video, an advertisement for Hovis bread, was viewed only once by participants. Participants were asked to follow with their eyes one object for the entirety of the video. Full details of the questions are given in Appendix E. Procedure The experiment took place in a well-lit room with no distractions that may have garnered attention. Participants firstly received an information sheet that briefly explained the study (see appendix F). All participants then signed a consent form (see appendix G) to formally provide their consent to take part. Before each of the saccade tasks, participants were given time to ask any questions they had. Once they confirmed they understood the experiment, the test trials began. All groups completed the eye-tracking tasks in a pre-defined order. The PST was completed first to avoid carry-over effects previously reported by Roberts et al. (1994), followed by the AST, and lastly the videos task. Participants were offered breaks in-between each task to ensure they did not become distracted or bored. It took no longer than 45 minutes to complete all tasks. Once the experiment had finished, participants were handed a debrief sheet explaining the aims of the study (see appendix H). Analyses To analyse the videos, total dwell times to the question relevant interest areas were compared to total dwell times to these interest areas when the participants viewed the same video freely. For example, to analyse the trial were participants were asked to count the windows when viewing the Gordon Brown video, a number of interest areas were created around the windows (see appendix I). The total dwell times inside these areas were then compared to the total dwell times inside these areas when participants viewed the same video freely.
This is part of an on-going EPSRC funded MoDEM study approved by the NHS to Dr Crawford
Do foetuses have the ability to retrieve and retain information presented by both the mother-to-be and partner?
language, foetus, mother-to-be, partner, retention
The complex phenomenon of language development is a vital criterion for communication and for the strengthening of the attachment bond between caregiver and baby (Chew & Ng, 2021). The period in which humans begin to process speech is difficult to define; previous research has identified that foetuses that have the capacity to retain linguistic information presented to them over six weeks by their mother-to-be show a preference for this information postnatally (DeCasper and Spence, 1986). However, the language environment of the foetus also likely incorporates that of the secondary carer role and very little research has investigated the role of the partner in influencing language retention. This study aims to investigate the extent to which foetuses have the ability to retrieve and retain linguistic input presented to them by both their mother-to-be and their partner. A within-measures design with two participant pairs who were recruited via opportunistic sampling through Lancaster University’s Babylab was conducted. Participants were asked to record themselves reading “The Cat in the Hat” and play both of the recordings to the foetus every day for two weeks. During these sessions, the mother-to-be was required to count the frequency of kicks and the movement intensity per session. The findings concluded that foetuses can retrieve and retain language that is presented over a two-week period at only 32 weeks’ gestation. Foetal kicking decreased significantly as exposure to recordings increased. This provides evidence of online processing of linguistics at 32 weeks’ gestation, implying that the full six-week exposure, as previous research indicated, is not necessary thus providing evidence of an innate processing of language. Although there is scope of environmental influence on this. No significant impact of parent recording on foetal ability to process language was found. This suggests that humans have an innate ability to process linguistic information which is despite levels of exposure to voice. However, this conclusion is based on a null hypothesis in an underpowered study; it would be very beneficial for further research to use a larger sample size to increase statistical power and be more representative of the general public.
Methods: Ethics Statement: Ethical approval was granted by Lancaster University Psychology Department on the 12th of April 2021 before any data collection was completed. Participants were provided with information for review and asked to complete an informed consent form online before participating within this experiment and were given the option to withdraw at any point of the study. Participants: Three mothers-to-be and their partners were recruited via opportunistic sampling through Lancaster University BabyLab social media (http://wp.lancs.ac.uk/babylab/) and word of mouth in exchange for a £5 book voucher from Waterstones. In order to take part in this research mothers-to-be must live with a partner and also have a foetal gestation age of between 32-34 weeks. If any participants were bilingual, they were asked to record the story in English to ensure reliability. Materials and Measures: Due to current restrictions because of COVID-19, this experiment took place online. Participants were sent an email containing a link to a Qualtrics survey. Qualtrics is a software that allows participants to access surveys and questionnaires on all digital devices at any point of time to help aid easy distribution. Qualtrics Survey: To complete this survey, participants were required to have access to a mobile device or computer. The Survey contained the information sheet, consent form, instructions, and demographic questions. The questionnaire consisted of questions asking the mother-to-be to rate the intensity of movements and state the frequency of kicking per session (see Appendix A). The intensity of kicks were recorded using a scale bar where mothers-to-be could rate the intensity of the kicking per session (0-100). Recording “The Cat in the Hat”: Participants were given a copy of an extract from “The Cat in the Hat” and both the mother- to-be and their Partner were asked to record themselves reading the story aloud using a device that they were then able to play the recording on every day for two weeks. This was estimated to take between five and ten minutes depending on reading speed per participant. To control the decibel of their recordings, parents were advised to download the “Decibel X” app which can monitor sound level in order to keep it at the recommended 90db (Luu, T, 2011). Also, to help mothers track their foetal kicks, they were also advised to download the NHS “kicks count” app which helped mothers-to-be accurately count the frequency of kicks per story session. At the end of the survey and after completion of the study, participants were given a debrief sheet which contained the aims of the research study and any contact information they might need for further questions. Design: This research study used a within-measures design as all participants took part in all sections of the experiment. The independent variables in the study were the parent reading the story which has two levels; the mother-to-be or their partner. The second independent variable related to the time point from day one until the end of the two weeks. The dependent variables were the frequency and intensity of foetal kicking during the exposure to both the mother-to- be and their partners recording of “The Cat in the Hat”. This was measured by the mother-to- be. Procedure: Once they had consented, the mother to be and partner were given an extract from the story “The Cat in the Hat” via the Qualtrics survey and were asked to record themselves individually reading the story on a device that they were able to play back on several occasions. Once the story had been recorded by both the mother-to-be and their partner, they were asked to play the story to the foetus every day for two weeks. The order of presentation was counterbalanced. While the study was being recorded, the mother was required to monitor the intensity and frequency of kicks that occurred for the duration of the auditory exposure. The mother-to- be was told to do this for both the duration of exposure to the recordings every day and then upload the outcomes for each session using the original Qualtrics survey link. Analysis: Rstudio is a professional software that allows for programming statistical analysis, production of graphs and tables that were used to analyse that data collected. Linear mixed effects model was conducted for analysis.
Do trustworthiness judgements help people to recognise synthetic faces?
StyleGAN, synthetic face, trustworthiness perception, facial trustworthiness
Recent advances in digital image generative models have allowed for artificial creation of fake imagery such as synthesising highly photorealistic human faces. Style-based Generative Adversarial Networks (StyleGAN) is one of the most state-of-the-art generative models in this field, and has been widely used on facial image generation. However, with the increasing ease of using such image generative models, the security in many domains, such as forensic, border control and mass media, is vulnerable in front of the potential threats resulted from the misuse of image generative technologies. To date there has only been limited empirical research into the facial characteristics of StyleGAN-generated faces to support the design of detection methods against such synthetic faces. This study used StyleGAN2 (an improved version of StyleGAN) to generate faces and invited people to complete two facial image evaluation tasks, 1) Discrimination task, 2) Trustworthiness rating task. The study results demonstrated that, in the discrimination task, subjects had trouble recognising synthetic faces by direct/explicit judgement; while in the trustworthiness rating task, subjects perceived the synthetic faces as significantly more trustworthy than real faces. The study further analysed gender bias and ethnicity bias on the perception of facial trustworthiness, with results showing some differences between different levels of gender and ethnicity. In conclusion, people’s ability to recognise synthetic faces is poor, but it is possible that people rely on the perception of facial trustworthiness to discriminate synthetic from real faces. The findings in this study have implications for the development of detection methods against digitally generated faces.
Three hundred and fifty-seven subjects (114 males, mean age = 25.2, SD = 5.8; 227 females, mean age = 25.0, SD = 6.3; 10 non-binary, mean age = 23.6, SD = 8.93) were recruited to complete an online survey test delivered on www.qualtrics.com. The responses of subjects who started but did not complete the online survey were eliminated to avoid distorting the research results. We used computer-synthesised facial images in this research as fake faces, mixed with real faces to examine people’s ability to detect fake faces and perceptual differences of trustworthiness between real/fake faces. Subjects did not get rewards for their participation, though they could see the test score of their performances at the end of the survey. The Qualtrics survey was based on a within-subjects design in which all subjects viewed the same two sets of adult facial images and completed each of the two tasks. To eliminate the effect of between-sets difference, the use of each image sets was counterbalanced in the individual test for each subject. Before the survey started, all subjects provided informed consent and completed a demographic questionnaire about their age, gender, ethnicity. In terms of the experimental power of 0.8 and significance level of 0.05, with a small effect, the power calculation indicated that the study needed at least 198 subjects. Stimuli A total of thirty-two human facial images (1024×1024 resolution), including 16 real and 16 synthetic faces, were used as stimuli in the survey. All real faces were taken from a publicly available dataset for high-quality human facial images, Flickr-Faces-HQ (FFHQ), which is created as a benchmark for GAN (see https://github.com/NVlabs/ffhq-dataset), and all synthetic faces were gained from the dataset of the generative image modeling, StyleGAN2 (see https://github.com/NVlabs/stylegan2). To ensure a diverse dataset, in each of the two sets of faces, there were 4 Black, 4 East Asian, 4 South Asian, 4 White, and 2 males and 2 females for each ethnicity. Among the sixteen faces of each set, half of them were real and half were synthetic, but this was unknown to subjects.
Subjects and design Three hundred and fifty-seven subjects (114 males, mean age = 25.2, SD = 5.8; 227 females, mean age = 25.0, SD = 6.3; 10 non-binary, mean age = 23.6, SD = 8.93) were recruited to complete an online survey test delivered on www.qualtrics.com. The responses of subjects who started but did not complete the online survey were eliminated to avoid distorting the research results. We used computer-synthesised facial images in this research as fake faces, mixed with real faces to examine people’s ability to detect fake faces and perceptual differences of trustworthiness between real/fake faces. Subjects did not get rewards for their participation, though they could see the test score of their performances at the end of the survey. The Qualtrics survey was based on a within-subjects design in which all subjects viewed the same two sets of adult facial images and completed each of the two tasks. To eliminate the effect of between-sets difference, the use of each image sets was counterbalanced in the individual test for each subject. Before the survey started, all subjects provided informed consent and completed a demographic questionnaire about their age, gender, ethnicity. In terms of the experimental power of 0.8 and significance level of 0.05, with a small effect, the power calculation indicated that the study needed at least 198 subjects. Stimuli A total of thirty-two human facial images (1024×1024 resolution), including 16 real and 16 synthetic faces, were used as stimuli in the survey. All real faces were taken from a publicly available dataset for high-quality human facial images, Flickr-Faces-HQ (FFHQ), which is created as a benchmark for GAN (see https://github.com/NVlabs/ffhq-dataset), and all synthetic faces were gained from the dataset of the generative image modeling, StyleGAN2 (see https://github.com/NVlabs/stylegan2). To ensure a diverse dataset, in each of the two sets of faces, there were 4 Black, 4 East Asian, 4 South Asian, 4 White, and 2 males and 2 females for each ethnicity. Among the sixteen faces of each set, half of them were real and half were synthetic, but this was unknown to subjects.