2-Minute Neuroscience: Ventral Tegmental Area (VTA)

The ventral tegmental area, or VTA, is one of the two largest dopaminergic regions of the brain (the other being the substantia nigra). Dopamine neurons leave the VTA in several different pathways and project throughout the brain. Two of the most prominent pathways are the mesocortical and mesolimbic pathways. The mesocortical pathway projects from the VTA to widespread areas of the cerebral cortex and has diverse functions including motivation, emotion, and executive functions. The mesolimbic pathway projects from the VTA to several limbic structures; the largest projection is to the nucleus accumbens. The mesolimbic pathway also has diverse functions but is best known for its role in processing rewarding stimuli.

For an article (on my website) that explains the ventral tegmental area, click this link: https://neuroscientificallychallenged...

TRANSCRIPT:

Welcome to 2 minute neuroscience, where I simplistically explain neuroscience topics in 2 minutes or less. In this installment I will discuss the ventral tegmental area.

The ventral tegmental area, or VTA, is found in the midbrain, situated next to the substantia nigra. Although the VTA contains several types of neurons, it is primarily characterized by its large population of dopamine neurons. It is one of the two major dopaminergic areas in the brain (the other being the substantia nigra). VTA dopamine neurons travel from the VTA to other areas of the brain in several major pathways. Two of the most prominent pathways are the mesocortical and the mesolimbic pathways.

The mesocortical pathway projects from the VTA to widespread areas of the cerebral cortex, including the prefrontal, orbitofrontal, and cingulate cortices as well as sensory and motor cortices. The mesocortical projections are very diverse and the pathway is involved in a wide range of functions including motivation, emotion, and executive functions.

The mesolimbic pathway projects from the VTA to several limbic structures. The largest projection of this pathway is to the nucleus accumbens, but other projections stretch to areas like the amygdala as well. The mesolimbic pathway also has diverse functions, but it is most frequently associated with the reward system, as dopamine signaling along the mesolimbic pathway is considered to be important to the processing of rewarding experiences. When someone uses an addictive drug, for example, dopamine neurons in the VTA are activated. These neurons project to the nucleus accumbens via the mesolimbic pathway, and their activation causes dopamine levels in the nucleus accumbens to rise. The effects of these increased dopamine levels are still not fully understood, but they may be involved with encoding memories about rewarding experiences and attributing importance to environmental stimuli that are associated with the reward.

References:

Oades RD, Halliday GM. Ventral tegmental (A10) system: neurobiology. 1. Anatomy and connectivity. Brain Res. 1987 May;434(2):117-65.

Pierce RC, Kumaresan V. The mesolimbic dopamine system: the final common pathway for the reinforcing effect of drugs of abuse? Neurosci Biobehav Rev. 2006;30(2):215-38. Epub 2005 Aug 11.