Autism and Glutamate

In recent years there has been a growing interest in the role played by the excitatory neurotransmitter glutamate in autism spectrum disorders. The present chapter describes results from brain imaging and biochemical studies that directly or indirectly strengthen the notion of dysfunctional glutamatergic transmission in autism spectrum disorders. Of particular interest is the increasing number of studies showing white matter, including corpus callosum, abnormalities and deficient cortical “connectivity” in autism. Accumulating biochemical evidence also points to aberrations in glutamatergic signalling in autism. Several studies testing different agents that modulate glutamatergic transmission have been conducted but larger placebo-controlled studies are needed. An alternative possible avenue involves combined dopaminergic and serotonergic stabilization which would mediate indirect modulation of glutamatergic systems.