Identifying the Functional Architecture of the Human Ventral Tegmental Area and the Substantia Nigra using High Resolution Magnetic Resonance Imaging
Mariam Eapen* and John C. Gore§
*Neuroscience Graduate Program, Vanderbilt University Medical School, U1205 Medical Center North, Nashville, TN 37232, USA.
§Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN 37232, USA.
Correspondence to M.E. e-mail: firstname.lastname@example.org
ABSTRACT | The ventral tegmental area (VTA) and the substantia nigra pars compacta (SNc) are subcortical areas within the ventral midbrain that are primary synthesizers of the neurotransmitter, dopamine (DA). Dopaminergic neurons from these areas have widespread projections to many subcortical and cortical parts of the brain. However, to date, the In vivo studies in rodents and non-human primates have shown that the dopaminergic neurons in the VTA and SNc are similar in their firing properties and release of DA1,2,39. However, these firing patterns are believed to facilitate multiple functional roles associated with reward related learning, motivation, and other goal directed behaviors1,50,51,60.
Since most of the studies on the VTA and SNc have been done in non-human species, it is difficult to translate this work into humans and accurately characterize the functional role of these two regions in normal human brain function. Non-invasive functional magnetic resonance imaging (fMRI) is one technique used to study human brain function in vivo. In particular, high resolution fMRI performed in ultra high field magnets (7 Tesla) can be especially beneficial in segmenting the anatomical substructure of brain areas in close proximity. This paper reviews the anatomical layout and functional significance of the VTA and SNc and proposes the use of ultra high field high resolution MRI to study the functional architecture of these two midbrain areas.