Equivalent own name bias in autism: An EEG study of the Attentional Blink

Indistinguishable behavioural and neural correlates of perceptual self-other distinction in autistic and neurotypical adults

Previous research has suggested that self-bias (i.e., enhanced cognitive processing of self-versus other-relevant information) may be atypical in autism spectrum conditions (ASC), perhaps due to difficulties with self-other distinction. However, empirical evidence for this is inconsistent, and the neural basis of processing differences remains unknown. We present two experiments that aimed to test perceptual self-bias and familiarity effects in ASC using a perceptual-association task. Participants were asked to distinguish face/label associations of the self from those of other people of differing levels of familiarity (i.e., friend vs stranger). Experiment 1 took an individual differences approach by testing whether behavioural self-bias is associated with the number of autistic traits in a neurotypical adult sample (N = 59). Experiment 2 took a case-control approach by testing whether behavioural self-bias and associated ERP responses differ between neurotypical (N = 27) and autistic (N = 30) adults. Across both experiments, behavioural results showed that participants experienced a self-bias (self > friend and stranger) and a familiarity effect (e.g., friend > stranger); neither effect was affected by the number of autistic traits or autism diagnosis. In Experiment 2, analysis of N1, N2, and P3 ERP components revealed a typical self-bias in both groups (self distinct from friend and stranger), and only the autistic group showed evidence of a familiarity effect (N2 more negative-going for stranger than friend). The findings are discussed in relation to self-other distinction ability, and the relevance of other neuropsychological and psychiatric conditions such as anxiety and alexithymia are also considered.

Electrophysiological correlates of self-related processing in adults with autism

The term "self-bias" refers to the human propensity to prioritize self- over other-related stimuli and is believed to influence various stages of the processing stream. By means of event-related potentials (ERPs), it was recently shown that the self-bias in a shape-label matching task modulates early as well as later phases of information processing in neurotypicals. Recent claims suggest autism-related deficits to specifically impact later stages of self-related processing; however, it is unclear whether these claims hold based on current findings. Using the shape-label matching task while recording ERPs in individuals with autism can clarify which stage of self-related processing is specifically affected in this condition. Therefore, this study sought to investigate the temporal course of self-related processing in adults with and without autism. Thirty-two adults with autism and 27 neurotypicals completed a shape-label matching task while ERPs were concomitantly recorded. At the behavioral level, results furnished evidence for a comparable self-bias across groups, with no differences in task performance between adults with and without autism. At the ERP level, the two groups showed a similar self-bias at early stages of self-related information processing (the N1 component). Conversely, the autism group manifested a lessened differentiation between self- and other-related stimuli at later stages (the parietal P3 component). In line with recent claims of later phases of self-related processing being altered in autism, we found an equivalent self-bias between groups at an early, sensory stage of processing, yet a strongly diminished self-bias at a later, cognitive stage in adults with autism.

Differences in own-face but not own-name discrimination between autistic and neurotypical adults: A fast periodic visual stimulation-EEG study

Self-related processing is thought to be altered in autism, with several studies reporting that autistic individuals show a diminished neural response relative to neurotypicals for their own name and face. However, evidence remains scarce and is mostly based on event-related potential studies. Here, we used EEG to measure the neural activity of autistic adults (20 for faces, 27 for names) and neurotypical adults (24 for faces, 25 for names) while they were watching rapidly alternating faces and names, through a relatively new technique called Fast Periodic Visual Stimulation. We presented strangers' faces or names at a base frequency of 5.77 Hz, while one's own, a close other's, and a specific stranger's face/name was presented at an oddball frequency of 1.154 Hz. The neurotypical group showed a significantly greater response to their own face than both close other and stranger faces, and a greater response for close other than for stranger faces. In contrast, in the autism group, own and close other faces showed stronger responses than the stranger's face, but the difference between own and close other faces was not significant in a bilateral parieto-occipital cluster. No group differences in the enhanced response to familiar names were found. These results replicate and extend results obtained using traditional electroencephalographic techniques which suggest atypical responses to self-relevant stimuli in autism.

The relevance of familiarity in the context of self-related information processing

Humans are inclined to preferentially process self-related content, referred to as the "self-bias." Different paradigms have been used to study this effect. However, not all paradigms included a familiar other condition (but rather an unfamiliar other condition), needed to differentiate self-specific effects from the impact of familiarity. The primary goal of our study was to test the suitability for studying the self-bias of two paradigms that provide robust measures of salience effects-that is, the Repetition Blindness (RB) effect and the Emotional Stroop (ES) interference-while addressing the familiarity confound. We further explored whether self-bias effects were related to autism symptomatology, as a reduced self-bias in autism has been reported in previous research. In an online procedure, 82 adults performed an RB task and an ES task in a counterbalanced order, while being presented with both self- and familiar other-related stimuli. Results of both frequentist and Bayesian analyses did not provide evidence in favour of a specific self-bias on either task: we found no significant modulation of the RB effect, nor of the ES interference, for the own versus a close other's name. Moreover, no link with autism symptomatology was found. Tackling a crucial shortcoming from earlier studies, our investigation raises awareness on the importance of accounting for familiarity when investigating self-related processing.

Specificity in the processing of a subject's own name

Subject's own name (SON) is widely used in both daily life and the clinic. Event-related potential (ERP)-based studies have previously detected several ERP components related to SON processing; however, as most of these studies used SON as a deviant stimulus, it was not possible to determine whether these components were SON-specific. To identify SON-specific ERP components, we adopted a passive listening task with EEG data recording involving 25 subjects. The auditory stimuli were a SON, a friend's name (FN), an unfamiliar name (UN) selected from other subjects' names and seven different unfamiliar names (DUNs). The experimental settings included Equal-probabilistic, Frequent-SON, Frequent-FN and Frequent-UN conditions. The results showed that SON consistently evoked a frontocentral SON-related negativity (SRN) within 210-350 ms under all conditions, which was not detected with the other names. Meanwhile, a late positive potential evoked by SON was found to be affected by stimulus probability, showing no significant difference between the SON and the other names in the Frequent-SON condition, or between the SON and a FN in the Frequent-UN condition. Taken together, our findings indicated that the SRN was a SON-specific ERP component, suggesting that distinct neural mechanism underly the processing of a SON.