Which neurotransmitters are most associated with autism?

• A. GABA, Serotonin, and Glutamate
• B. Dopamine and Norepinephrine
• C. Acetylcholine and Histamine
• D. Serotonin Alone

Answer: (A)

Autism is linked to disruptions in how brain cells communicate, especially in the balance between inhibitory and excitatory signaling and how serotonin modulates those systems. GABA is the primary inhibitory transmitter, and glutamate is the main excitatory one; abnormalities in these two systems can disrupt neural circuits and connectivity implicated in autism. Serotonin also plays a role in mood, social behavior, and development, with evidence of altered serotonergic functioning in individuals with autism. Together, these three neurotransmitters—GABA, glutamate, and serotonin—best reflect the neurochemical patterns most consistently discussed in autism research. Dopamine and norepinephrine influence attention and motivation but don’t show the same broad, established association across autism neurobiology. Serotonin alone misses the broader picture of inhibitory/excitatory balance and its developmental implications.