The serotonin pathways in OCD

The principal serotonin centres in the brain are the caudal and rostral raphe nuclei. Transmission of serotonin ascending from the rostral raphe nuclei to the basal ganglia, thalamus, limbic cortex and cerebral cortex is decreased in OCD compared with normal. The other major pathways for serotonin transmission which project to the cerebellum and descending the spinal cord, remain unchanged.

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