Changing Faces: Dynamic Emotional Face Processing in Autism Spectrum Disorder Across Childhood and Adulthood

An ALE meta-analysis of the neural evidence of facial emotion processing in autism

OBJECTIVE

Facial emotion recognition is central to successful social interaction. People with autism spectrum disorder (ASD) have difficulties in this area. However, neuroimaging evidence on facial emotion processing in ASD has been diverse. This study aims to identify common and consistent brain activity patterns during facial emotion processing in autism.

METHODS

Following PRISMA guidelines, 22 fMRI studies (539 ASD, 502 typically developing participants (TD) were included.

RESULTS

Both groups showed significant activation in the right fusiform gyrus (FG) and left fusiform face area (FFA). In addition, TD participants showed increased left amygdala activity. Compared to TD, ASD individuals had increased activation in the right cerebellum lobule VI and left secondary visual cortex. Age-based subgroup analysis showed that ASD children showed increased activity in bilateral FG, and ASD adults and TD children in the right FG. Finally, adults from both groups had increased activity in the right FG in the within-group and conjunction analyses.

CONCLUSIONS

These results suggest that ASD and TD engage core face processing areas similarly while TD may use core and an extended social brain network. Findings of this study underscore the role of fusiform face area in facial emotion processing along with more insights into the neural processing of facial emotions.

The influence of dynamism and expression intensity on face emotion recognition in individuals with autistic traits

Face emotion recognition (FER) ability varies across the population, with autistic traits in the general population reported to contribute to this variation. Previous studies used photographs of posed facial expressions, while real social encounters involve dynamic expressions of varying intensity. We used static photographs and dynamic videos, showing peak and partial facial expressions to investigate the influence of dynamism and expression intensity on FER in non-clinical adults who varied in autistic traits. Those with high autistic traits had lower accuracy with both static peak and dynamic partial intensity expressions, when compared to low autistic trait participants. Furthermore, high autistic traits were linked to an accuracy advantage for dynamic compared with static stimuli in both partial and peak expression conditions, while those with low autistic traits demonstrated this dynamic advantage only for partial expressions. These findings reveal the differing importance of dynamism and expression intensity for FER across the non-clinical population and appear linked to self-reported social-communication skills. Furthermore, FER difficulties in autism might relate to the ability to integrate subtle, dynamic information, rather than static emotion categorisation alone.

Functional brain network alterations in the co-occurrence of autism spectrum disorder and attention deficit hyperactivity disorder

Autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD) are two highly prevalent and commonly co-occurring neurodevelopmental disorders. The neural mechanisms underpinning the comorbidity of ASD and ADHD (ASD + ADHD) remain unclear. We focused on the topological organization and functional connectivity of brain networks in ASD + ADHD patients versus ASD patients without ADHD (ASD-only). Resting-state functional magnetic resonance imaging (rs-fMRI) data from 114 ASD and 161 typically developing (TD) individuals were obtained from the Autism Brain Imaging Data Exchange II. The ASD patients comprised 40 ASD + ADHD and 74 ASD-only individuals. We constructed functional brain networks for each group and performed graph-theory and network-based statistic (NBS) analyses. Group differences between ASD + ADHD and ASD-only were analyzed at three levels: nodal, global, and connectivity. At the nodal level, ASD + ADHD exhibited topological disorganization in the temporal and occipital regions, compared with ASD-only. At the global level, ASD + ADHD and ASD-only displayed no significant differences. At the connectivity level, the NBS analysis revealed that ASD + ADHD showed enhanced functional connectivity between the prefrontal and frontoparietal regions, as well as between the orbitofrontal and occipital regions, compared with ASD-only. The hippocampus was the shared region in aberrant functional connectivity patterns in ASD + ADHD and ASD-only compared with TD. These findings suggests that ASD + ADHD displays altered topology and functional connectivity in the brain regions that undertake social cognition, language processing, and sensory processing.

Oxytocin impacts top-down and bottom-up social perception in adolescents with ASD: a MEG study of neural connectivity

BACKGROUND

In the last decade, accumulative evidence has shown that oxytocin can modulate social perception in typically developed individuals and individuals diagnosed with autism. While several studies show that oxytocin (OT) modulates neural activation in social-related neural regions, the mechanism that underlies OT effects in ASD is not fully known yet. Despite evidence from animal studies on connections between the oxytocinergic system and excitation/inhibition neural balance, the influence of OT on oscillatory responses among individuals with ASD has been rarely examined. To bridge these gaps in knowledge, we investigated the effects of OT on both social and non-social stimuli while focusing on its specific influence on the neural connectivity between three socially related neural regions-the left and right fusiform and the medial frontal cortex.

METHODS

Twenty-five adolescents with ASD participated in a wall-established social task during a randomized, double-blind placebo-controlled MEG and OT administration study. Our main task was a social-related task that required the identification of social and non-social-related pictures. We hypothesized that OT would modulate the oscillatory connectivity between three pre-selected regions of interest to be more adaptive to social processing. Specifically, we focused on alpha and gamma bands which are known to play an important role in face processing and top-down/bottom-up balance.

RESULTS

Compared to placebo, OT reduced the connectivity between the medial frontal cortex and the fusiform in the low gamma more for social stimuli than for non-social ones, a reduction that was correlated with individuals' performance in the task. Additionally, for both social and non-social stimuli, OT increased the connectivity in the alpha and beta bands.

LIMITATIONS

Sample size was determined based on sample sizes previously reported in MEG in clinical populations, especially OT administration studies in combination with neuroimaging in ASD. We were limited in our capability to recruit for such a study, and as such, the sample size was not based on a priori power analysis. Additionally, we limited our analyses to specific neural bands and regions. To validate the current results, future studies may be needed to explore other parameters using whole-brain approaches in larger samples.

CONCLUSION

These results suggest that OT influenced social perception by modifying the communication between frontal and posterior regions, an attenuation that potentially impacts both social and non-social early perception. We also show that OT influences differ between top-down and bottom-up processes, depending on the social context. Overall, by showing that OT influences both social-related perception and overall attention during early processing stages, we add new information to the existing understanding of the impact of OT on neural processing in ASD. Furthermore, by highlighting the influence of OT on early perception, we provide new directions for treatments for difficulties in early attentional phases in this population. Trial registration Registered on October 27, 2021-Retrospectively registered, https://clinicaltrials.gov/ct2/show/record/NCT05096676 (details on clinical registration can be found in www.

CLINICALTRIAL

gov , unique identifier: NCT05096676 ).

Sensory Perception Mechanism for Preparing the Combinations of Stimuli Operation in the Architectural Experience

Sensory stimuli in an architectural space play an important role in the human perception of the indoor environment, no matter whether they are static or dynamic, isolated, or combined. By enhancing some perceptions in the sensory stimuli, the overall perceptions of an architectural space can be improved, especially for an intelligent architectural space. As yet, there are few studies reported about the sensory perception mechanism for the sensory stimuli operation in the architectural experience. In this research, a wooden micro building was prepared for the study of the sensitivity level of participants to various sensory stimuli in the same and in different sensory domains. Participants’ visual, auditory, olfactory, tactile and kinaesthesia perceptions were discussed statistically in terms of the sensitivity level. Based on the study, the effect of a single dynamic sensory stimulus (a dynamically coloured light) on the participants’ perception was studied in a paper architectural model from two aspects including preference and emotion. The dynamically coloured light was discussed statistically in terms of the level of preference. The study showed that there are significant differences among participants’ levels of sensitivity to the different sensory domains and to the different sensory stimuli. In particular, the sensitivity level to the stimulus that is the colour of a space is the highest of all stimuli. As a single changing sensory stimulus, a dynamically coloured light can lead to significant mood fluctuations and changes in the preference level. In particular, yellow is the favourite colour of light. The object of this study is expected to provide a theoretical foundation that is related to sensory choice, sensory perception enhancement and the combination forms of sensory perceptions. Based on the theoretical foundation, the perception design of overlapped multi-sensory stimuli and a single dynamic stimulus can be conducted to improve the quality of the indoor environment of normal and intelligent multi-sensory architecture.

An Android for Emotional Interaction: Spatiotemporal Validation of Its Facial Expressions

Android robots capable of emotional interactions with humans have considerable potential for application to research. While several studies developed androids that can exhibit human-like emotional facial expressions, few have empirically validated androids' facial expressions. To investigate this issue, we developed an android head called Nikola based on human psychology and conducted three studies to test the validity of its facial expressions. In Study 1, Nikola produced single facial actions, which were evaluated in accordance with the Facial Action Coding System. The results showed that 17 action units were appropriately produced. In Study 2, Nikola produced the prototypical facial expressions for six basic emotions (anger, disgust, fear, happiness, sadness, and surprise), and naïve participants labeled photographs of the expressions. The recognition accuracy of all emotions was higher than chance level. In Study 3, Nikola produced dynamic facial expressions for six basic emotions at four different speeds, and naïve participants evaluated the naturalness of the speed of each expression. The effect of speed differed across emotions, as in previous studies of human expressions. These data validate the spatial and temporal patterns of Nikola's emotional facial expressions, and suggest that it may be useful for future psychological studies and real-life applications.