Dynamic and static brain functional abnormalities in autism patients at different developmental stages

Abstract

To date, most studies on autism spectrum disorder (ASD) have focused on specific age ranges, while the mechanisms underlying the entire developmental process of autism patients remain unclear. The aim of this study was to investigate the alterations in brain function in autistic individuals at different developmental stages by resting-state functional MRI (rs-fMRI). We obtained rs-fMRI data from 173 ASD and 178 typical development (TD) individuals in Autism Brain Imaging Data Exchange, spanning child, adolescent, and adult groups. We characterized local brain activity using the amplitude of low-frequency fluctuations (ALFFs), regional homogeneity (ReHo), dynamic ALFF (dALFF), and dynamic ReHo (dReHo) metrics. Pearson correlation analyses were conducted on relationships between Autism Diagnostic Observation Schedule scores and activity measures in abnormal brain regions. We found abnormal ALFF values in the medial and lateral orbitofrontal gyrus and right insula cortex with ASD compared with the TD group. In addition, compared with adolescents with ASD, we found that adults with ASD exhibited an increase in dReHo values in the posterior lateral frontal lobe. We also found that changes in ALFF were associated with the severity of autism. We found abnormal activity in multiple brain regions in individuals with autism and correlated it with clinical characteristics. Our results may provide some help for further exploring the age-related neurobiological mechanisms of ASD patients.

Fig. 1

Brain regions showing differences between ASD and TD adults. (a–c) ALFF, ReHo, dReHo differences between ASD and TD groups. ALFF, amplitude of low-frequency fluctuation; ASD, autism spectrum disorder; dReHo, dynamic regional homogeneity; ReHo, regional homogeneity; TD, typical development.

Fig. 2

Brain regions with statistically significant differences in ReHo values between ASD and TD adolescents. ASD, autism spectrum disorder; ReHo, regional homogeneity; TD, typical development.

Fig. 3

Brain regions with statistically significant differences in ALFF values between ASD and TD children. ALFF, amplitude of low-frequency fluctuation; ASD, autism spectrum disorder; TD, typical development.

Fig. 4

Local differences between ASD adults and ASD adolescents. (a) Brain regions with different ALFF values. (b) Brain regions with different ReHo values. (c) Brain regions with different dReHo values. (d) The positive correlation between ALFF values in the left medial frontal gyrus and ADOS total scores. (e) The negative correlation between ALFF values in the right inferior cerebellum and ADOS total scores. (f) The positive correlation between ReHo values in the left lentiform nucleus and ADOS total scores. ADOS, Autism Diagnostic Observation Schedule; ALFF, amplitude of low-frequency fluctuation; ASD, autism spectrum disorder; dReHo, dynamic regional homogeneity; ReHo, regional homogeneity.

Fig. 5

Local differences between ASD adolescents and ASD children. (a) Brain regions with different ALFF values. (b) Brain regions with different ReHo values. (c) Brain regions with different dReHo values. ALFF, amplitude of low-frequency fluctuation; ASD, autism spectrum disorder; dReHo, dynamic regional homogeneity; ReHo, regional homogeneity.