Misdirected neurons may underlie autism symptoms - SFARI Many people with autism are known to be overly sensitive to sensory stimuli, such as sound or light. However, the reasons for this, as well as for other symptoms of autism, remain poorly understood. Autism probably results from ‘abnormal’ junctions, or synapses, that connect neurons. This hypothesis is based largely on the many genes known to function at the synapse — such as SHANK3, NLGN1 and FMR1 — that have been found to be mutated in individuals with autism. It is also based on imaging studies that have reported altered functional connections between brain regions in people with autism.