Cerebral cortex serotonergic innervations

Kosofsky BE, Molhver ME The serotonergic innervation of cerebral cortex different classes of axon terminals arise from dorsal and median raphe nuclei. Synapse 1 153-168, 1987... 

The serotonergic neurons of the raphe nuclei in the brainstem innervate the entire brain and likely exert substantial modulatory effects on our perceptions, emotions, thought processes, and conscious awareness— the mental states that may collectively be called the mind. Psilocybin and related tryptamines from Psilocybe fungi are believed to produce their profound effects on the brain and mind by way of interacting with 5-HT2A receptors in the cerebral cortex, limbic system, and elsewhere. As chemical probes that might lead to a better understanding of how the neural circuitry of the brain is related to the nature of mind, they offer unprecedented opportunities ... 

The development of serotonergic innervation to the cerebral cortex has been characterized in neonatal rats by immunohistochemical techniques and autoradiographic imaging. These experiments demonstrate early serotonergic innervation that could be involved in a transient physiological role in sensory areas of the cortex or exert a trophic influence on the development of cortical circuitry and thalamocortical connections [76]. 

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