Amygdala is the area of the brain that interprets sensory input's social and emotional meaning, from recognizing emotions in faces to solving fearful images. Autism has historically been associated with difficulties with social behaviour that are thought to be mediated by the Amygdala.
Typically, overgrowth begins between 6 and 12 months of age, before the onset of hallmark behaviours associated with autism. Amygdala growth in infants who later developed autism differed markedly from brain growth patterns in children with fragile X syndrome, another neurodevelopmental disorder. Researchers used magnetic resonance imaging (MRI) to demonstrate that the Amygdala grows excessively in infancy.
When diagnosed with autism a year later, children with faster-growing amygdalas demonstrate more social difficulties. The findings of this study are the first to show amygdala overdevelopment before the onset of symptoms of autism. The study was conducted by the Infant Brain Imaging Study (IBIS) Network, a consortium of ten universities in the United States and Canada. Early problems in processing visual and sensory information may lead to an overgrowth of the Amygdala due to increased stress on the Amygdala.
A study suggests that an optimal time to start interventions for infants at the highest risk of developing autism maybe during the first year of life. Amygdalas overgrowth has been linked to chronic stress in studies of other psychiatric conditions (e.g., depression and anxiety). The observation may provide a clue to understanding the development of autism in children.
Citation:
University of North Carolina Health Care. (2022, March 25). Scientists identify overgrowth of key brain structure in babies who later develop autism. ScienceDaily. Retrieved June 16, 2022 from www.sciencedaily.com/releases/2022/03/220325093829.htm