Anatomical organization of the basal ganglia

Published on June 2, 2014   46 min

Other Talks in the Series: Parkinson's Disease

0:00
Welcome to this Henry Stewart talk devoted to the anatomical organization of the basal ganglia. My name is Andre Parent. I am professor of neuroscience at the University Laval in Quebec City, Canada.
0:18
The aim of this presentation is to provide an overall review of the basal ganglia organization, based on that I gathered from the current literature, as well as a result of our own morphological studies of the basal ganglia undertaken in humans and non-human primates. The talk is divided into four distinct parts. The first part concerns the overall organization of the basal ganglia. A special attention will be paid to the dual basal ganglia model, which is widely used to explain the functional organization of the sets of subcortical structures in both health and disease. The second part summarizes the result of our own single-axon tracing studies of the various basal ganglia components in monkeys. The third part is devoted to the presence of dopaminergic neurons within the primate striatum. The last part of the presentation reviews evidence for the persistence of neurogenesis in the striatum of adult primates.
1:35
This drawing of a coronal section through to primate forebrain provides an overall view of the topographical organization of the basal ganglia. The basal ganglia are a set of subcortical structures that are reciprocally linked with the cerebral cortex via a relay in the thalamus. The main axis of this basal ganglia cortical loop includes the following sequentially-arranged elements. First, the striatum, divided into two main nuclei-- the caudate nucleus, labeled CD, and the putamen, labeled PUT. The striatum is the largest and major integrative component of the basal ganglia. Second, the pallidum, or globus pallidus, comprising an external segment, labeled GPe, and an internal segment, labels GPi. The latter nucleus is a major output structure of the basal ganglia. Third, the substantia nigra, divided into a pars compacta, labeled SNc, and a pars reticulata, labeled SNr. The pars reticulata of the substantia nigra is another major output structure of the basal ganglia. Finally, the ventral tier thalamic nuclei, labeled Th in this drawing, whose premotor neurons convey the information that has been processed through the basal ganglia back through the cerebral cortex. Various control or modulating structure also plays a crucial role in the functional organization of the basal ganglia. Among those are the subthalamic nucleus, labeled STN, which is reciprocally linked with the external pallidum And the substantia nigra pars compacta, labeled SNc, whose dopaminergic neurons project massively to the striatum. Various other brain stem and thalamic nuclei also exert a significant modulating influence upon the basal ganglia components. But for the sake of clarity, these structures have not been included in this drawing.
Hide

Anatomical organization of the basal ganglia

Embed in course/own notes