central olfactory pathways
Last reviewed 01/2018
The olfactory tract from the nasal smell receptors has a complex path from the olfactory bulb. Some mitral and tufted cell axons synapse with olfactory nuclei along the tract. Tertiary neurones from the latter pass via the anterior commissure to the contralateral olfactory bulb.
The rest of the olfactory tract divides at the anterior perforated substance of the brain into groups of striae. The medial olfactory stria passes to the septal area and thence on to hippocampus, hypothalamus and upper brainstem. The lateral olfactory stria passes to cortex - the preamygdaloid and prepiriform cortices. From here, signals are passed diffusely to centres involved with emotion, autonomic responses, and higher processing, e.g. the secondary olfactory cortex of the parahippocampal gyrus.