The ventral posterior nucleus is divided into:

The ventral posterior nucleus is the somato-sensory relay nucleus in thalamus of the brain.

The ventral posterior nucleus receives neuronal input from the medial lemniscus, spinal lemniscus, spinothalamic tracts, and trigeminothalamic tract.

The axons of many of these neurones terminate in the thalamus (for example the ventral posterior nucleus, VPN), others terminate in the reticular system or the cerebellum.

The zona incerta avoids the thalamus nuclei of the primary sensory areas such as the ventral posterior nucleus of the somatosensory system and the lateral geniculate of the visual system.

Visual input from the optic tract is processed by the lateral geniculate nucleus of the thalamus, auditory input in the medial geniculate nucleus, and somatosensory input in the ventral posterior nucleus of the thalamus.

In general terms, the highest density of parvalbumin stain is in the nuclei of the ventral nuclear group (i.e. in the ventral anterior, ventral lateral and ventral posterior nuclei) and in the medial and lateral geniculate nuclear groups.

Similarly the medial geniculate nucleus acts as a key auditory relay between the inferior colliculus of the midbrain and the primary auditory cortex, and the ventral posterior nucleus is a key somatosensory relay, which sends touch and proprioceptive information to the primary somatosensory cortex.