Here’s a list of abstracts and links to the lead author papers I’ve published over my career. Enjoy and do feel free to get in touch if you have any questions or interesting thoughts.

Visual Processing

Kiat, J.E., Hayes, T.R., Henderson, J.M., Luck, S.J. (2022). Rapid extraction of the spatial distribution of physical saliency and semantic informativeness from natural scenes in the human brain. Journal of Neuroscience, 97-108

Physically salient objects are thought to attract attention in natural scenes. However, research has shown that meaning maps—which capture the spatial distribution of semantically informative scene features—trump physical saliency in predicting the pattern of eye moments in natural scene viewing. Meaning maps even predict the fastest eye movements, suggesting that the brain extracts the spatial distribution of potentially meaningful scene regions very rapidly. To test this hypothesis, we applied representational similarity analysis (RSA) to event-related potential (ERP) data. The ERPs were obtained from human participants (N = 32, male and female) who viewed a series of 50 different natural scenes while performing a modified 1-back task. For each scene, we obtained a physical saliency map from a computational model and a meaning map from crowd-sourced ratings. We then used RSA to assess the extent to which the representational geometry of physical saliency maps and meaning maps can predict the representational geometry of the neural response (the ERP scalp distribution) at each moment in time following scene onset. We found that a link between physical saliency and the ERPs emerged first (ca. 78 ms after stimulus onset), with a link to semantic informativeness emerging soon afterward (ca. 87 ms after stimulus onset). These findings are in line with previous evidence indicating that saliency is computed rapidly, while also indicating that information related to the spatial distribution of semantically informative scene elements is computed shortly thereafter, early enough to potentially exert an influence on eye movements.

Kiat, J.E., Luck, S.J., Beckner, A.G., Hayes, T.R., Pomaranski, K.I., Henderson, J.M., Oakes, L.M. (2022). Linking Patterns of Infant Eye Movements to a Neural Network Model of the Ventral Stream Using Representational Similarity Analysis. Developmental Science.

Little is known about the development of higher-level areas of visual cortex during infancy, and even less is known about how the development of visually guided behavior is related to the different levels of the cortical processing hierarchy. As a first step toward filling these gaps, we used representational similarity analysis (RSA) to assess links between gaze patterns and a neural network model that captures key properties of the ventral visual processing stream. We recorded the eye movements of 4- to 12-month-old infants (N = 54) as they viewed photographs of scenes. For each infant, we calculated the similarity of the gaze patterns for each pair of photographs. We also analyzed the images using a convolutional neural network model in which the successive layers correspond approximately to the sequence of areas along the ventral stream. For each layer of the network, we calculated the similarity of the activation patterns for each pair of photographs, which was then compared with the infant gaze data. We found that the network layers corresponding to lower-level areas of visual cortex accounted for gaze patterns better in younger infants than in older infants, whereas the network layers corresponding to higher-level areas of visual cortex accounted for gaze patterns better in older infants than in younger infants. Thus, between 4 and 12 months, gaze becomes increasingly controlled by more abstract, higher level representations. These results also demonstrate the feasibility of using RSA to link infant gaze behavior to neural network models.

Kiat, J.E. (2018). Assessing cross-modal target transition effects with a visual-auditory oddball. International Journal of Psychophysiology.

Prior research has shown contextual manipulations involving temporal and sequence related factors significantly moderate attention-related responses, as indexed by the P3b event-related-potential, towards infrequent (i.e., deviant) target oddball stimuli. However, significantly less research has looked at the influence of cross-modal switching on P3b responding, with the impact of target-to-target cross-modal transitions being virtually unstudied. To address this gap, this study recorded high-density (256 electrodes) EEG data from twenty-five participants as they completed a cross-modal visual-auditory oddball task. This task was comprised of unimodal visual (70% Nontargets: 30% Deviant-targets) and auditory (70% Nontargets: 30% Deviant-targets) oddballs presented in fixed alternating order (i.e., visual-auditory-visual-auditory, etc.) with participants being tasked with detecting deviant-targets in both modalities. Differences in the P3b response towards deviant-targets as a function of preceding deviant-target’s presentation modality was analyzed using temporal-spatial PCA decomposition. In line with predictions, the results indicate that the ERP response to auditory deviant-targets preceded by visual deviant-targets exhibits an elevated P3b, relative to the processing of auditory deviant-targets preceded by auditory deviant-targets. However, the processing of visual deviant-targets preceded by auditory deviant-targets exhibited a reduced P3b response, relative to the P3b response towards visual deviant-targets preceded by visual deviant-targets. These findings provide the first demonstration of temporally and perceptually decoupled target-to-target cross-modal transitions moderating P3b responses on the oddball paradigm, generally providing support for the context-updating interpretation of the P3b response.

Kiat, J.E., Dodd, M.D., Belli, R.F. Cheadle, J.E. (2018). The Signature of Undetected Change: An Exploratory Electrotomographic Investigation of Gradual Change Blindness. Journal of Neurophysiology

Neuroimaging based investigations of change blindness, a phenomenon in which seemingly obvious changes in visual scenes fail to be detected, have significantly advanced our understanding of visual awareness. The vast majority of prior investigations, however, utilize paradigms involving visual disruptions (e.g. intervening blank screens, saccadic movements, “mudsplashes”), making it difficult to cleanly isolate neural responses towards undetected visual changes. To address this issue in this present study, high-density EEG data (256 channel) was collected from 25 participants using a paradigm in which visual changes were progressively introduced into detailed real-world scenes without the use of visual disruption. Oscillatory activity associated with undetected changes was contrasted with activity linked to their absence using standardized Low Resolution brain Electromagnetic Tomography (sLORETA). Increased beta-2 activity in the right inferior parietal lobule (rIPL), a region repeatedly associated with change blindness in disruption paradigms, followed by increased theta activity in the right superior temporal gyrus (rSTG) was noted in undetected visual change responses relative to the absence of change. We propose the rIPL beta-2 activity to be associated with orienting attention towards visual changes with the subsequent rise in rSTG theta activity being potentially linked with updating preconscious perceptual memory representations.

SOCIAL ATTENTION

Young people frequently socialize together in contexts that encourage risky decision making, pointing to a need for research into how susceptibility to peer influence is related to individual differences in the neural processing of decisions during sequentially escalating risk. We applied a novel analytic approach to analyze EEG activity from college-going students while they completed the Balloon Analogue Risk Task (BART), a well-established risk-taking propensity assessment. By modeling outcome-processing-related changes in the P200 and feedback-related negativity (FRN) sequentially within each BART trial as a function of pump order as an index of increasing risk, our results suggest that analyzing the BART in a progressive fashion may provide valuable new insights into the temporal neurophysiological dynamics of risk taking. Our results showed that a P200, localized to the left caudate nucleus, and an FRN, localized to the left dACC, were positively correlated with the level of risk taking and reward. Furthermore, consistent with our hypotheses, the rate of change in the FRN was higher among college students with greater self-reported resistance to peer influence.

Kiat, J.E., Cheadle, J.E. (2018). Tick-Tock Goes the Croc: A High-Density EEG Investigation of Risk-Taking Reactivity and Binge-Drinking Susceptibility. Social Cognitive & Affective Neuroscience

Links between individual differences in risk processing and high-risk behaviors such as binge drinking have long been the focus of active research. However, investigations in this area almost exclusively utilize decision-making focused paradigms. This emphasis makes it difficult to assess links between risk behaviors and raw risk reactivity independent of decision and feedback processes. A deeper understanding of this association has the potential to shed light on the role of risk reactivity in high-risk behavior susceptibility. To contribute towards this aim, this study utilizes a popular risk-taking game, the crocodile dentist, to assess links between individual differences in decision-free risk-reactivity and reported binge drinking frequency levels. In this task, participants engage in a series of decision-free escalating risk responses. Risk-reactivity was assessed by measuring Late Positive Potential responses towards risk-taking action initiation cues using high-density 256-Channel EEG. The results indicate that, after controlling for overall alcohol consumption frequency, higher rates of reported binge drinking are associated with both increased general risk-taking responsivity and increased risk-reactivity escalation as a function of risk level. These findings highlight intriguing links between risk reactivity and binge drinking frequency, making key contributions in the areas of risk-taking and affective science.

Kiat, J.E., Cheadle, J.E. (2017). The Impact of Individuation on the Bases of Human Empathic Responding. Neuroimage. 155, 312-321.

While there is substantial overlap in the neural systems underlying empathy for people we know as opposed to strangers, social distance has been shown to significantly moderate empathic neural responses towards the negative experiences of others. Intriguingly however, variance in empathic neural responses towards known and unknown targets has not been reflected by behavioral differences as indexed by self-reported empathic ratings. One explanation for this disconnect is that empathic evaluations of known and unknown individuals draw on different bases (e.g. target identity/reactions) within the empathic process. To test this hypothesis, we utilized high density EEG to assess how individuating targets with personal names moderated the link between behavioral pain ratings and attentional processing oriented towards (a) initial target processing and (b) subsequent expressions target discomfort. Consistent with prior findings, no differences in pain ratings between individuated and unindividuated targets was observed. However, individual mean pain rating differences for individuated targets was strongly positively related to attentional processing levels, indexed by the P300, during the initial presentation of those targets, a relationship absent for unindividuated targets. In contrast, pain ratings for unindividuated targets was positively related to levels of attentional processing, indexed by the Late Positive Potential (LPP), during the subsequent discomfort expression stage. Furthermore, the LPP response to individuated target discomfort was positively linked to behavioral measures of emotional expressivity whereas the LPP response to unindividuated target discomfort was positively associated with cognitive appraisal. These findings suggest that individuation can significantly shift the bases of empathic responding.

Kiat, J.E., Cheadle, J.E. Goosby, B.J. (2018). The Impact of Social Exclusion on Anticipatory Attentional Processes. International Journal of Psychophysiology.

The importance of understanding how we anticipate and prepare for social rejection is underscored by the mental and physical toll of continual social vigilance. In this study, we investigate the impact of social rejection on anticipatory attentional processes using the well-known Cyberball task, a paradigm in which participants engage in a game of catch with virtual avatars who after an initial period of fair-play (inclusion condition) then exclude the participant from the game (exclusion condition). The degree of anticipatory attention allocated by subjects towards the avatars was assessed by measuring P3b responses towards the avatars’ preparatory actions (i.e. the phase preceding their exclusionary actions) using high density EEG. The results of the study show that relative to the inclusion, participants exhibit elevated levels of anticipatory attentional allocation towards the avatars during the exclusion block. This shift was however significantly moderated by participants’ self-reported cognitive regulation tendencies. Participants with higher levels of self-reported cognitive reappraisal tendencies showed larger anticipatory P3b increases from the inclusion to exclusion block relative to participants with reduced levels of reappraisal tendencies. These results highlight the impact of social exclusion on anticipatory neural processing and the moderating role of cognitive reappraisal on these effects.

Kiat, J.E., Straley, E., Cheadle, J. E. (2017). Why Won’t They Sit with Me? An Exploratory Investigation of Stereotyped Cues, Social Exclusion, and the P3b. Social Neuroscience

The importance of understanding how we anticipate and prepare for being socially excluded is underscored by the numerous adverse mental and physical consequences of social rejection. In this study, we adapted a social exclusion paradigm, the Lunchroom task, to investigate the use of social context cues in the formation of social outcome expectations as indexed by the P3b, an ERP component associated with attention orientation and context updating. In this task, Black and White participants were presented with either neutral or stereotyped cues prior to being exposed to simulated inclusion versus exclusion outcome scenarios. Black participants showed evidence of (1) a significantly reduced P3b response to exclusions preceded by stereotyped cues relative to neutral cue-related exclusions and (2) a marginally significant increase in the P3b response to inclusions relative to exclusions when both were preceded by stereotyped cues. Both of these findings suggest a key role for the use of social cues in the formation of outcome expectations. In line with our hypothesis that the random intermixing of inclusion and exclusion outcomes would prevent formation of outcome expectations when coupled with the absence of self-relevant cues, no overall P3b modulations were observed among a comparison group of White participants.

Memory Projects

Kiat, J.E., Belli, R.F. (2017). An Exploratory High-Density EEG Investigation of the Misinformation Effect: Attentional and Recollective Differences between True and False Perceptual Memories. Neurobiology of Learning & Memory

The misinformation effect, a phenomenon in which eyewitness memories are altered via exposure to post-event misinformation, is one of the most important paradigms used to investigate the reconstructive nature of human memory. The aim of this study was to use the misinformation effect paradigm to investigate differences in attentional and recollective processing between true and false event memories. Nineteen participants completed a variant of the misinformation paradigm in which recognition responses to true and misinformation based event details embedded within a narrative context, were investigated using high-density (256-channel) EEG with a 1-day delay between event exposure and test. Source monitoring responses were used to isolate event-related-potentials (ERPs) associated with perceptual (i.e. event) source attributions. Temporal-spatial analyses of these ERPs showed evidence of an elevated P3b and Late-Positive Component, associated with stronger context-matching responses and recollective activity respectively, in true perceptual memories relative to false misinformation based ones. These findings represent the first retrieval focused EEG investigation of the misinformation effect and highlight the interplay between attention and retrieval processes in episodic memory recognition.

Kiat, J.E., Belli, R.F. (2018). Attentional responses on an auditory oddball predict false memory susceptibility. Cognitive, Affective & Behavioral Neuroscience

Attention and memory are highly integrated processes. Building on prior behavioral investigations, this study assesses the link between individual differences in low-level neural attentional responding and false memory susceptibility on the misinformation effect, a paradigm in which false event memories are induced via misleading post-event information. Twenty-four subjects completed the misinformation effect paradigm after which high-density (256-channel) EEG data was collected as they engaged in an auditory oddball task. Temporal-spatial decomposition was used to extract two attention-related components from the oddball data, the P3b and Classic Slow Wave. The P3b was utilized as an index of individual differences in salient target attentional responding while the slow wave was adopted as an index of variability in task-level sustained attention. Analyses of these components show a significant negative relationship between slow-wave responses to oddball non-targets and perceptual false memory endorsements, suggestive of a link between individual differences in levels of sustained attention and false memory susceptibility. These findings provide the first demonstrated link between individual differences in basic attentional responses and false memory. These results support prior behavioral work linking attention and false memory and highlight the integration between attentional processes and real-world episodic memory.

Kiat, J.E., Belli, R.F. (2018). The role of individual differences in visual\verbal information processing preferences in visual\verbal source monitoring. Journal of Cognitive Psychology.

Researchers have long sought to understand individual differences in false memory susceptibility. One particularly interesting direction in this area looks at individual differences in visual versus verbal styles of information processing. Prior work linking individual differences in these cognitive styles with false memory susceptibility has been mixed, likely due to a lack of research that distinguishes between visual and verbal styles as independent factors. The current study addresses this issue by linking independent visual and verbal scores on the Style of Processing scale with performance on a Picture-Word source-monitoring task in which 82 participants indicated if various objects were previously presented to them as words or images. The results of this study show that higher visual style of processing preferences are associated with improved levels of visual source-monitoring ability as indexed by a reduced number of source-monitoring errors involving the misattribution of verbally presented items to a visual source.

Education Research

Kiat, J. E., Ong, A. R., & Ganesan, A. (2017). The influence of Distractor Strength and Placement on MCQ Responding. Educational Psychology.

Multiple-choice questions (MCQs) play a key role in standardized testing and in-class assessment. Research into the influence of within item response order on MCQ characteristics has been mixed. While some researchers have shown preferential selection of response options presented earlier in the answer list, others have failed to replicate these results. This paper investigates a possible explanation for these mixed findings by assessing the influence of distractor strength on MCQ response order effects. A real-world assessment was administered to 232 undergraduates in which the response order within items was systematically varied. A generalised multilevel model was then used to show a significant interaction between distractor strength and response position with regard to response behaviour. Furthermore, the effect was found to be independent of student ability. These findings have implications for MCQ test construction, minimising the negative consequences of MCQ test exposure and promoting improved test-taking strategies.