Visual attention affects late somatosensory processing in autism spectrum disorder

Abstract

Purpose

Somatosensory processing problems are often reported in individuals with autism spectrum disorder (ASD), along with an abnormal multimodal integration of visual, tactile or proprioceptive information. However, the effects of visual stimulation and attention on somatosensory processing in ASD remain unknown. This study explores the effects of visual attention on somatosensory processing in ASD.

Materials and Methods

The neural activity in somatosensory areas and associated regions was investigated by measuring somatosensory evoked potentials (SEPs) elicited by median nerve stimulation, in three different conditions (closed eyes, open eyes and focused attention to a visual task). Nine individuals with ASD and nine typically developing (TD) individuals participated in the study.

Results

There were significant interactions between groups (ASD, TD) and conditions (closed eye, open eye, visual task requiring focused attention) for P100-N140 SEP amplitudes evaluated by 2-way analysis of variance. Post hoc analyses revealed that the P100-N140 amplitude with closed eyes recorded larger SEPs in the ASD group than in the TD group at C3′ of the international 10–20 system. In the ASD group, the P100-N140 amplitude elicited smaller responses during visual tasks than with closed or open eyes. There were no significant differences in N20-P25 SEP components.

Conclusions

These findings suggest that visual attention affects the later stages of somatosensory processing in individuals with ASD.

Keywords:

• Somatosensory evoked potentials
• autism
• visual attention
• cross modal effect
• sensory processing

Acknowledgements

We would like to thank Professor Toshio Higashi for helping with the experimental setup. We also like to thank Sumihisa Honda for helping with the statistical analyses.

Authors’ contributions

HN, AT and RI conceived and planned the experiments. HN conducted the experiments. All authors contributed to the interpretation of the results. HN took the lead in writing the manuscript. AI contributed by confirming diagnoses. All authors provided critical feedback and helped shape the research, analysis and manuscript.

Disclosure statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.