5-HT2A is expressed widely throughout the central nervous system. It is expressed near most of the serotoninergic terminal rich areas, including neocortex (mainly prefrontal, parietal, and somatosensory cortex) and the olfactory tubercle. Especially high concentrations of this receptor on the apical dendrites of pyramidal cells in layer V of the cortex may modulate cognitive processes, working memory,and attention.
Russo, E.B., Burnett, A., Hall, B., and Parker, K.K. (2005). Agonistic properties of cannabidiol at 5-HT1a receptors. Neurochem. Res. 30, 1037–1043.