The autistic brain can process local but not global emotion regularities in facial and musical sequences

Auditory Global-Local Processing Under Tonal Language Background: Effect of Attention and Autistic Traits

PURPOSE

Neurotypical individuals show a robust "global precedence effect (GPE)" when processing hierarchically structured visual information. However, the auditory domain remains understudied. The current research serves to fill the knowledge gap on auditory global-local processing across the broader autism phenotype under the tonal language background.

METHOD

This study examined auditory global-local processing styles in 37 Mandarin-speaking young adults (age: M = 20.35, SD = 2.32; 19 males) with varying autistic traits. The participants were required to judge global and local pitch structures in nine-tone melodies with both congruent and incongruent conditions under both directed attention and divided attention modes.

RESULTS

We found that GPE persisted independent of the attention modes during hierarchical processing. Autistic traits were among the potential contributors that reshaped GPE in auditory global-local processing under a tonal language background.

CONCLUSIONS

Our study provides an initial investigation into auditory global-local processing among Mandarin-speaking individuals across a range of autistic traits, revealing the presence of the GPE effect during hierarchical pitch structure processing. The advantage of global processing versus local processing expanded with increasing autistic traits, providing further support for the notion that auditory global processing may remain intact in autism and the broader phenotype. We highlight that GPE is a process of coarse-to-fine integration of sensory perception and cognitive feedback iteration, which both top-down and bottom-up processes wield influence on. These findings have implications for the study of atypical auditory processing in autism and may help to refine the early diagnosis and auditory-based intervention for autism.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.28114118.

Erroneous predictive coding across brain hierarchies in a non-human primate model of autism spectrum disorder

In autism spectrum disorder (ASD), atypical sensory experiences are often associated with irregularities in predictive coding, which proposes that the brain creates hierarchical sensory models via a bidirectional process of predictions and prediction errors. However, it remains unclear how these irregularities manifest across different functional hierarchies in the brain. To address this, we study a marmoset model of ASD induced by valproic acid (VPA) treatment. We record high-density electrocorticography (ECoG) during an auditory task with two layers of temporal control, and applied a quantitative model to quantify the integrity of predictive coding across two distinct hierarchies. Our results demonstrate a persistent pattern of sensory hypersensitivity and unstable predictions across two brain hierarchies in VPA-treated animals, and reveal the associated spatio-spectro-temporal neural signatures. Despite the regular occurrence of imprecise predictions in VPA-treated animals, we observe diverse configurations of underestimation or overestimation of sensory regularities within the hierarchies. Our results demonstrate the coexistence of the two primary Bayesian accounts of ASD: overly-precise sensory observations and weak prior beliefs, and offer a potential multi-layered biomarker for ASD, which could enhance our understanding of its diverse symptoms.

Predictive processing of music and language in autism: Evidence from Mandarin and English speakers

Atypical predictive processing has been associated with autism across multiple domains, based mainly on artificial antecedents and consequents. As structured sequences where expectations derive from implicit learning of combinatorial principles, language and music provide naturalistic stimuli for investigating predictive processing. In this study, we matched melodic and sentence stimuli in cloze probabilities and examined musical and linguistic prediction in Mandarin- (Experiment 1) and English-speaking (Experiment 2) autistic and non-autistic individuals using both production and perception tasks. In the production tasks, participants listened to unfinished melodies/sentences and then produced the final notes/words to complete these items. In the perception tasks, participants provided expectedness ratings of the completed melodies/sentences based on the most frequent notes/words in the norms. While Experiment 1 showed intact musical prediction but atypical linguistic prediction in autism in the Mandarin sample that demonstrated imbalanced musical training experience and receptive vocabulary skills between groups, the group difference disappeared in a more closely matched sample of English speakers in Experiment 2. These findings suggest the importance of taking an individual differences approach when investigating predictive processing in music and language in autism, as the difficulty in prediction in autism may not be due to generalized problems with prediction in any type of complex sequence processing.