Atypical eye contact in autism: Models, mechanisms and development

An atypical pattern of eye contact behaviour is one of the most significant symptoms of Autism Spectrum Disorder (ASD). Recent empirical advances have revealed the developmental, cognitive and neural basis of atypical eye contact behaviour in ASD. We review different models and advance a new ‘fast-track modulator model’. Specifically, we propose that atypical eye contact processing in ASD originates in the lack of influence from a subcortical face and eye contact detection route, which is hypothesized to modulate eye contact processing and guide its emergent specialization during development

Predicted action consequences are perceptually facilitated before cancellation

Models of action control suggest that predicted action outcomes are “cancelled” from perception, allowing agents to devote resources to more behaviorally relevant unexpected events. These models are supported by a range of findings demonstrating that expected consequences of action are perceived less intensely than unexpected events. A key assumption of these models is that the prediction is subtracted from the sensory input. This early subtraction allows preferential processing of unexpected events from the outset of movement, thereby promoting rapid initiation of corrective actions and updating of predictive models. We tested this assumption in three psychophysical experiments. Participants rated the intensity (brightness) of observed finger movements congruent or incongruent with their own movements at different timepoints after action. Across Experiments 1 and 2, evidence of cancellation—whereby congruent events appeared less bright than incongruent events—was only found 200 ms after action, whereas an opposite effect of brighter congruent percepts was observed in earlier time ranges (50 ms after action). Experiment 3 demonstrated that this interaction was not a result of response bias. These findings suggest that “cancellation” may not be the rapid process assumed in the literature, and that perception of predicted action outcomes is initially “facilitated.” We speculate that the representation of our environment may in fact be optimized via two opposing processes: The primary process facilitates perception of events consistent with predictions and thereby helps us to perceive what is more likely, but a later process aids the perception of any detected events generating prediction errors to assist model updating

Association between action kinematics and emotion perception across adolescence

Research with adults suggests that we interpret others’ internal states from kinematic cues, using models calibrated to our own action experiences. Changes in action production that occur during adolescence may therefore have implications for adolescents’ understanding of others. Here we examined whether, like adults, adolescents use velocity cues to determine others’ emotions, and whether any emotion perception differences would be those predicted based on differences in action production. We measured preferred walking velocity in groups of Early (11-12 years old), Middle (13-14 years old) and Late (16-18 years old) adolescents, and adults, and recorded their perception of happy, angry and sad ‘point-light walkers’. Preferred walking velocity decreased across age and ratings of emotional stimuli with manipulated velocity demonstrated that all groups used velocity cues to determine emotion. Importantly, the relative intensity ratings of different emotions also differed across development in a manner that was predicted based on the group differences in walking velocity. Further regression analyses demonstrated that emotion perception was predicted by own movement velocity, rather than age or pubertal stage per se. These results suggest that changes in action production across adolescence are indeed accompanied by corresponding changes in how emotions are perceived from velocity. These findings indicate the importance of examining differences in action production across development when interpreting differences in understanding of others

Perceptual prediction: rapidly making sense of a noisy world

Prior knowledge shapes what we perceive. A new brain stimulation study suggests that this perceptual shaping is achieved by changes in sensory brain regions before the input arrives, with common mechanisms operating across different sensory areas

Our own action kinematics predict the perceived affective states of others.

Our movement kinematics provideuseful cues aboutour affective states. Given that our experiences furnish models that help us to interpret our environment, and that a rich source of action experience comes from our own movements,the present study examined whetherwe use models of our own action kinematics to make judgments about the affective states of others. For example,relative to one’s typical kinematics, anger isassociated with fast movements. Therefore, the extent to which we perceive angerin others maybe determined by the degreeto which their movementsare faster than our own typicalmovements. We related participants’walking kinematicsin a neutral contextto their judgments of the affective statesconveyed byobserved point-light walkers(PLWs). Aspredicted,we found a linear relationship between one’s own walking kinematics and affective state judgments, such that faster participants rated sloweremotionsmore intensely relative to their ratings for faster emotions. This relationship was absent when observing PLWs where differences in velocity between affective states were removed. These findings suggest that perception of affective states in others is predicted by one’s own movement kinematics, withimportant implications for perception of, and interaction with,those who move differentl

Crossmodal classification of mu rhythm activity during action observation and execution suggests specificity to somatosensory features of actions.

The alpha mu rhythm (8-13 Hz) has been considered to reflect mirror neuron activity due to the fact that it is attenuated by both action observation and action execution. The putative link between mirror neuron system activity and the mu rhythm has been used to study the involvement of the mirror system in a wide range of socio-cognitive processes and clinical disorders. However, previous research has failed to convincingly demonstrate the specificity of the mu rhythm, meaning that it is unclear whether the mu rhythm reflects mirror neuron activity. It also remains unclear if mu rhythm suppression during action observation reflects the processing of motor or tactile information. In an attempt to assess the validity of the mu rhythm as a measure of mirror neuron activity, we used crossmodal pattern classification to assess the specificity of EEG mu rhythm response to action varying in terms of action type (whole-hand or precision grip), concurrent tactile stimulation (stimulation or no stimulation), or object use (transitive or intransitive actions) in twenty human participants. The main results reveal that above-chance crossmodal classification of mu rhythm activity was obtained in the central channels for tactile stimulation and action transitivity but not for action type. Furthermore, traditional univariate analyses applied to the same data were insensitive to differences between conditions. By calling into question the relationship between mirror system activity and the mu rhythm, these results have important implications for the use and interpretation of mu rhythm activity

Action biases perceptual decisions towards expected outcomes

We predict how our actions will influence the world around us. Prevailing models in the action control literature propose that we use these predictions to suppress or ‘cancel’ perception of expected action outcomes, to highlight more informative surprising events. However, contrasting normative Bayesian models in sensory cognition suggest that we are more, not less, likely to perceive what we expect–given that what we expect is more likely to occur. Here we adjudicated between these models by investigating how expectations influence perceptual decisions about action outcomes in a signal detection paradigm. Across three experiments, participants performed one of two manual actions that were sometimes accompanied by brief presentation of expected or unexpected visual outcomes.Contrary to dominant cancellation models but consistent with Bayesian accounts, we found that observers were biased to report the presence of expected action outcomes. There were no effects of expectation on sensitivity. Computational modelling revealed that the action-induced bias reflected a sensory bias in how evidence was accumulated rather than a baseline shift in decision circuits. Expectation effects remained in Experiments 2 and 3 when orthogonal cues indicated which finger was more likely to be probed (i.e.,task-relevant). These biases towards perceiving expected action outcomes are suggestive of a mechanism that would enable generation of largely veridical representations of our actions and their consequences in an inherently uncertain sensory world

Atypical emotion recognition from bodies is associated with perceptual difficulties in healthy aging.

A range of processes are required for recognizing others’ affective states. It is particularly important that we process the perceptual cues providing information about these states. These experiments tested the hypothesis that difficulties with affective state identification in older adults (OAs) arise, at least partly, from deficits in perceptual processing. To this end we presented “point light display” whole body stimuli to healthy OAs and comparison younger adults (YAs) in 3 signal detection experiments. We examined the ability of OAs to recognize visual bodily information—posture and kinematics—and whether impaired recognition of affective states can be explained by deficits in processing these cues. OAs exhibited reduced sensitivity to postural cues (Experiment 1) but not to kinematic cues (Experiment 2) in affectively neutral stimuli. Importantly, they also exhibited reduced sensitivity only to affective states conveyed predominantly through posture (Experiment 3) —that is, the cue they were impaired in perceiving. These findings highlight how affective state identification difficulties in OAs may arise from problems in perceptual processing and demonstrate more widely how it is essential to consider the contribution of perceptual processes to emotion recognition. (APA PsycInfo Database Record (c) 2019 APA, all rights reserved

Interaction takes two: typical adults exhibit mind-blindness towards those with Autism Spectrum Disorder

Recent work suggests that we are better at interpreting the movements of others who move like us, and that individuals with Autism Spectrum Disorder (ASD) move in a quantifiably different way from typical individuals. Therefore, ‘social impairments’ exhibited by individuals with ASD may, at least in part, represent a failure by typical individuals to infer the correct mental states from the movements of those with ASD. To examine this possibility, individuals with ASD and typical adults manually directed two triangles to generate animations depicting mental state interactions. Kinematic analysis of the generated animations demonstrated that the participants with ASD moved atypically, specifically with increased jerk compared to the typical participants. In confirmation of our primary hypothesis, typical individuals were better able to identify the mental state portrayed in the animations produced by typical, relative to autistic individuals. The participants with ASD did not show this ‘same group’ advantage, demonstrating comparable performance for the two sets of animations. These findings have significant implications for clinical assessment and intervention in ASD, and potentially other populations with atypical movement