Electrophysiological Correlates of Subliminal Perception of Facial Expressions in Individuals with Autistic Traits: A Backward Masking Study

The power of (surreptitiously) mentioning your mentor's name: Subliminal priming of mentor's name modulates N170 responses to blurred faces

Using the event-related potentials (ERPs) technique and subliminal priming paradigm, the present study examined the influence of mentioning a mentor's name on graduate students. Fifty-eight graduate students were subliminally primed by mentor and stranger names before making pressure judgments of a series of unrelated blurred facial photos with neutral emotion. The face-sensitive N170 components were analyzed according to the pressure judgment × name prime conditions. The results showed that relative to stranger names, subliminal priming of mentor's name could modulate students' N170 reactions during facial processing. Specifically, the mentor-name priming attenuated N170 amplitudes for high-pressure judgment trials on the right hemisphere but heightened the overall N170 responses on the left hemisphere. Behavioral results also showed that the mentor-name priming slowed students' reaction time during pressure judgments; in addition, students' attitudes towards mentors were correlated with N170 amplitudes on high-pressure judgment conditions. These findings provided neuroscientific evidence demonstrating the psychological significance of mentors to graduate students. Theoretical and practical implications were also discussed.

Neurotypicals with higher autistic traits have delayed visual processing of an approaching life-sized avatar's gait: an event-related potentials study

Introduction

Autism spectrum disorder (ASD) is a neurodevelopmental disorder, which is reportedly related to difficulties in the visual processing of human motion, such as biological motion and gestures. Moreover, neurotypical (here, we mention it as individuals without a diagnosis) adults with autistic traits are clumsier than those without autistic traits when passing by others. It is still unclear whether the clumsiness derived from atypical visual processing of another's approaching gait motion. We aim to address this question by investigating the association between autistic traits in neurotypical adults and the visual processing of an approaching life-sized avatar's gait.

Methods

We clarified a typical visual motion processing and autistic traits in daily life in 26 neurotypical adults by analyzing the subthreshold autism trait questionnaire (SATQ) score, a 24-item self-report scale of ASD, and event-related potentials (ERPs) in response to walking motion of a passing avatar. Videos of walking life-sized virtual avatars approaching and retreating were presented as visual stimuli.

Results and discussion

The association between the participants' SATQ scores and the latencies and amplitudes of the ERPs was examined. ERP components (N170 and P200) components were identified at T5 and T6 electrodes. Participants reporting higher SATQ scores had longer latencies of P200 at T6 and lower amplitudes of P200 at T5 and T6 electrodes for the approaching avatar than those reporting lower SATQ scores. These findings indicate that adults with autistic traits have delayed and less sensitive visual processing of the approaching avatar. It suggests that while passing another person, these individuals have atypical visual processing of their approach. This study may contribute to elucidating autistic traits from the perspective of visual processing in an environment simulating daily life.

Asynchronous neural oscillations associated with subliminal affective face priming in autism spectrum disorder

Autism spectrum disorder (ASD) is characterized by social communicative disturbance. Social communication requires rapid processing and accurate cognition regarding others' emotional expressions. Previous electrophysiological studies have attempted to elucidate the processes underlying atypical face-specific N170 responses to emotional faces in ASD. The present study explored subliminal affective priming effects (SAPEs) on the N170 response and time-frequency analysis of intertrial phase coherence (ITPC) for the N170 in ASD. Fifteen participants [seven participants with ASD and eight typically developing (TD) controls] were recruited for the experiment. Event-related potentials were recorded with a 128-channel electroencephalography device while participants performed an emotional face judgment task. The results revealed enhanced N170 amplitude for supraliminal target-face stimuli when they were preceded by subliminal fearful-face stimuli, in both the ASD and TD groups. Interestingly, TD participants exhibited higher alpha-ITPC in the subliminal fearful-face priming condition in the right face-specific area in the N170 time window. In contrast, there were no significant differences in ITPC in any frequency bands between the subliminal fearful and neutral priming conditions in the ASD group. Asynchronous phase-locking neural activities in the face-specific area may underlie impaired nonconscious face processing in ASD, despite the presence of common features of SAPEs for the N170 component in both the ASD and TD groups.

Neural Mechanisms of Subliminal Mentor-Student Relationship Stimuli Processing: An ERP Study

In educational contexts, mentorship roles often complicate the mentor-student relationship because mentors act not only as the closest academic ally of graduate students but also their program supervisors who can affect their timely graduation. This study examines how graduate students react to their mentors’ names when subliminally presented. A total of 63 graduate students (31 male; Mean Age = 23.450) were asked to perform an irrelevant color judgment task of valenced words (positive vs. negative relationship words) after a subliminal presentation of three different types of names (i.e., mentors, authorities, and friends). Results show that mentor and friend names elicit a greater P2 peak than authority names, whereas mentor names evoke a reduced N2 and P3 amplitude than friend and authority names. In addition, participants with a history of abusive supervision tend to have an overall decline in P2 amplitude. These event-related potential (ERP) findings suggest that mentors are perceived by students as familiar while attention-inducing figures.

The relationship between tendency to attend to detail, sensory sensitivity, and affective response to food cues - A registered report

Understanding the underlying drivers of food choice remains a challenge and has highlighted the need for measures that capture data over and above that offered by self-reporting tools. Consequently, a growing body of research has set out to interpret facial responses to food cues to offer a greater insight into the emotional responses that may drive food acceptance. However, interpreting facial responses is challenging, as there are numerous factors that may influence affective response to foods, including expectation, context, and individual differences. Existing findings suggest there is a link between autistic traits and sensory sensitivities; research highlights further links between sensory sensitivities and eating behaviour, and autistic traits and eating behaviour, with a body of research focusing on the autistic trait attention to detail (ATD). As such, the current study aimed to examine rapid facial activity in response to foods cues while capturing these individual differences present in the general population. This study found no evidence to suggest facial responses to food pictures were linked with attention to detail or hyper-sensitivity. The findings did support a general link between self-reported pleasantness ratings of viewed foods and activity of facial muscles. Post-hoc analyses suggested scoring on the social skills sub-scale of the Autism Quotient (AQ) was associated with levator activity while viewing pictures low in pleasantness. This study offers a greater understanding of variations, at the individual level, which are associated with affective response to foods, and may help to inform the development of tools that set out to predict food acceptance.

Gender differences in subliminal affective face priming: A high-density ERP study

INTRODUCTION

Subliminal affective priming effects (SAPEs) refer to the phenomenon by which the presentation of an affective prime stimulus influences the subsequent affective evaluation of a target stimulus. Previous studies have reported that unconsciously processed stimuli affect behavioral performance more than consciously processed stimuli. However, the impact of SAPEs on the face-specific N170 component is unclear. We studied how SAPEs for fearful faces affected the N170 for subsequent supraliminal target faces using event-related potentials (ERPs).

METHODS

Japanese adults (n = 44, 20 females) participated in this study. Subliminal prime faces (neutral or fearful) were presented for 17 ms, followed by a backward mask for 283 ms and 800 ms target faces (neutral, emotionally ambiguous, or fearful). 128-channel ERPs were recorded while participants judged the expression of target faces as neutral or fearful. Response rates and response times were also measured for assessing behavioral alterations.

RESULTS

Although the behavioral results revealed no evidence of SAPEs, we found gender-related SAPEs in right N170 amplitude. Specifically, female participants exhibited enhanced right N170 amplitude for emotionally neutral faces primed by fearful faces, while male participants exhibited decreased N170 amplitude in fearful prime trials with fearful target faces. Male participants exhibited significant correlations between N170 amplitude and behavioral response time in the fearful prime-neutral target condition.

CONCLUSIONS

Our ERP results suggest the existence of a gender difference in target-face processing preceded by subliminally presented face stimuli in the right occipito-temporal region.

Alterations in Rapid Social Evaluations in Individuals with High Autism Traits

Typically developing adults with low and high Autism Spectrum Quotient (AQ) scores made rapid social evaluations of neutral faces when these were primed by briefly presented emotional faces. High AQ participants rated neutral faces as more threatening than low AQ participants, regardless of the prime condition. Both groups rated target neutral faces as more threatening with fearful compared with neutral primes, while neither group demonstrated an effect of happy primes on the ratings of neutral target faces. These results demonstrate subtle anomalies in rapid visual processing of emotional faces across the broader autism spectrum. They suggest that higher autism traits may be associated with a generalized threat bias in rapid social evaluations.

How ubiquitous is the direct-gaze advantage? Evidence for an averted-gaze advantage in a gaze-discrimination task

Human eye gaze conveys an enormous amount of socially relevant information, and the rapid assessment of gaze direction is of particular relevance in order to adapt behavior accordingly. Specifically, previous research demonstrated evidence for an advantage of processing direct (vs. averted) gaze. The present study examined discrimination performance for gaze direction (direct vs. averted) under controlled presentation conditions: Using a backward-masking gaze-discrimination task, photographs of faces with direct and averted gaze were briefly presented, followed by a mask stimulus. Additionally, effects of facial context on gaze discrimination were assessed by either presenting gaze direction in isolation (i.e., by only showing the eye region) or in the context of an upright or inverted face. Across three experiments, we consistently observed a facial context effect with highest discrimination performance for faces presented in upright position, lower performance for inverted faces, and lowest performance for eyes presented in isolation. Additionally, averted gaze was generally responded to faster and with higher accuracy than direct gaze, indicating an averted-gaze advantage. Overall, the results suggest that direct gaze is not generally associated with processing advantages, thereby highlighting the important role of presentation conditions and task demands in gaze perception.

Brain Processes While Struggling With Evidence Accumulation During Facial Emotion Recognition: An ERP Study

The human brain is tuned to recognize emotional facial expressions in faces having a natural upright orientation. The relative contributions of featural, configural, and holistic processing to decision-making are as yet poorly understood. This study used a diffusion decision model (DDM) of decision-making to investigate the contribution of early face-sensitive processes to emotion recognition from physiognomic features (the eyes, nose, and mouth) by determining how experimental conditions tapping those processes affect early face-sensitive neuroelectric reflections (P100, N170, and P250) of processes determining evidence accumulation at the behavioral level. We first examined the effects of both stimulus orientation (upright vs. inverted) and stimulus type (photographs vs. sketches) on behavior and neuroelectric components (amplitude and latency). Then, we explored the sources of variance common to the experimental effects on event-related potentials (ERPs) and the DDM parameters. Several results suggest that the N170 indicates core visual processing for emotion recognition decision-making: (a) the additive effect of stimulus inversion and impoverishment on N170 latency; and (b) multivariate analysis suggesting that N170 neuroelectric activity must be increased to counteract the detrimental effects of face inversion on drift rate and of stimulus impoverishment on the stimulus encoding component of non-decision times. Overall, our results show that emotion recognition is still possible even with degraded stimulation, but at a neurocognitive cost, reflecting the extent to which our brain struggles to accumulate sensory evidence of a given emotion. Accordingly, we theorize that: (a) the P100 neural generator would provide a holistic frame of reference to the face percept through categorical encoding; (b) the N170 neural generator would maintain the structural cohesiveness of the subtle configural variations in facial expressions across our experimental manipulations through coordinate encoding of the facial features; and (c) building on the previous configural processing, the neurons generating the P250 would be responsible for a normalization process adapting to the facial features to match the stimulus to internal representations of emotional expressions.

Event-Related Potential to Conscious and Nonconscious Emotional Face Perception in Females with Autistic-Like Traits

This study explored the electrocortical correlates of conscious and nonconscious perceptions of emotionally laden faces in neurotypical adult women with varying levels of autistic-like traits (Autism Spectrum Quotient—AQ). Event-related potentials (ERPs) were recorded during the viewing of backward-masked images for happy, neutral, and sad faces presented either below (16 ms—subliminal) or above the level of visual conscious awareness (167 ms—supraliminal). Sad compared to happy faces elicited larger frontal-central N1, N2, and occipital P3 waves. We observed larger N1 amplitudes to sad faces than to happy and neutral faces in High-AQ (but not Low-AQ) scorers. Additionally, High-AQ scorers had a relatively larger P3 at the occipital region to sad faces. Regardless of the AQ score, subliminal perceived emotional faces elicited shorter N1, N2, and P3 latencies than supraliminal faces. Happy and sad faces had shorter N170 latency in the supraliminal than subliminal condition. High-AQ participants had a longer N1 latency over the occipital region than Low-AQ ones. In Low-AQ individuals (but not in High-AQ ones), emotional recognition with female faces produced a longer N170 latency than with male faces. N4 latency was shorter to female faces than male faces. These findings are discussed in view of their clinical implications and extension to autism.

The developmental origins of subliminal face processing

Sensitive responding to facial information is of key importance during human social interactions. Research shows that adults glean much information from another person's face without conscious perception, attesting to the robustness of face processing in the service of adaptive social functioning. Until recently, it was unclear whether such subliminal face processing is an outcome of extensive learning, resulting in adult face processing skills, or an early defining feature of human face processing. Here, we review recent research examining the early ontogeny and brain correlates of subliminal face processing, demonstrating that subliminal face processing: (1) emerges during the first year of life; (2) is multifaceted in response to transient (gaze, emotion) and stable (trustworthiness) facial cues; (3) systematically elicits frontal brain responses linked to attention allocation. The synthesized research suggests that subliminal face processing emerges early in human development and thus may play a foundational role during human social interactions. This offers a fresh look at the ontogenetic origins of unconscious face processing and informs theoretical accounts of human sociality.

Neurophysiological correlates of emotional face perception consciousness

Aim of the present study was to investigate the neurophysiologic correlates of the conscious and not conscious perception of faces (presented for 14, 40, 80 ms) with happy and sad emotional valence. Electroencephalographic data of 22 participants during a report-based visual task were recorded. Both happy and sad faces presented for 14 ms showed a longer N170 latency compared to the faces presented for 40 and 80 ms. A shorter latency of early components (before N170) was found in the right hemisphere and a longer latency in the left one in response to the happy faces presented for 14 ms compared to those presented for longer times. The faces presented for 14 ms, declared as consciously perceived, evoked a higher brain response compared to those declared as not perceived. Parietal and cingulate brain areas showed a lower intensity of the brain response to the consciously perceived faces in the early components. Happy faces showed a greater brain response when consciously detected, while the sad faces induced a greater brain response when not consciously detected. The findings suggest that the N170 may be the epiphenomenon of an earlier consciously detection. Moreover, these preliminary results seem to support a main role of parietal and cingulate brain areas into not conscious perception.

Awareness of Emotional Expressions in Cannabis Users: An Event-Related Potential Study

Cannabis use has been associated with anxiogenic effects when used in low frequency for a short duration, but cannabis can also have anxiogenic effects when used heavily for a long duration. Animal studies have indicated the neurobiological mechanisms related to cannabis and anxiety; however, research has been limited on the related neurocognitive mechanisms. Previous research has indicated that cannabis use is associated with alterations in event-related potentials (ERPs). The purpose of the current study was to examine anxiety related attentional processing of emotional expressions using ERP methods. We used a backward masking paradigm to restrict awareness of facial expressions (i.e., fearful, happy, and neutral). The results indicated that cannabis use was associated with differences in emotional processing. Specifically, the results suggested cannabis users had increased P1 amplitudes toward happy facial expressions compared to fearful and neutral. Additionally, cannabis users seemed to have reduced N170 hemisphere lateralization.