The lentiform nucleus, or lenticular nucleus, comprises the putamen and the globus pallidus within the basal ganglia. With the caudate nucleus, it forms the dorsal striatum. It is a large, lens-shaped mass of gray matter just lateral to the internal capsule.
What are two pathways of communication between the cortex and the basal ganglia?
There are two distinct pathways that process signals through the basal ganglia: the direct pathway and the indirect pathway. These two pathways have opposite net effects on thalamic target structures.
What is the function of the lenticular nucleus?
Answer: The lentiform nucleus is comprised of the putamen and globus pallidus of the basal ganglia. As part of the basal ganglia, it carries out complex functions related to movement, cognition, and emotion. The lentiform nucleus is part of the forebrain (telencephalon).
What is disinhibition in the basal ganglia?
Disinhibition in the direct and indirect pathways through the basal ganglia. As a result, the subthalamic cells become more active and, by virtue of their excitatory synapses with cells of the internal globus pallidus and reticulata, they increase the inhibitory outflow of the basal ganglia.
What is the meaning of Lentiform?
1. lentiform – convex on both sides; shaped like a lentil. biconvex, convexo-convex, lenticular. bulging, convex – curving or bulging outward.
What are the pathways of the basal ganglia (BG)?
Four parallel pathways exist within the BG which participate in different functions: Input to the Basal Ganglia [See Figure 16.5] Substantia nigra pars compacta provides input to the striatum, which is dopaminergic in nature and has both excitatory and inhibitory actions within the striatum Output from the Basal Ganglia [See Figure 16.6]
What is the difference between basal ganglia and nucleus?
The term basal ganglia in the strictest sense refers to nuclei embedded deep in the brain hemispheres (striatum or caudate-putamen and globus pallidus), whereas related nuclei consist of structures located in the diencephalon (subthalamic nucleus), mesencephalon (substantia nigra), and pons (pedunculopontine nucleus).
How does output output leave the basal ganglia?
Output leaves the BG via the internal segment of the globus pallidus and the substantia nigra pars reticulata. Four parallel pathways exist within the BG which participate in different functions: Input to the Basal Ganglia [See Figure 16.5]
Is there a canonical basal ganglia model?
Some insight on the canonical basal ganglia model is provided, together with a selection of paradoxes and some views over the horizon in the field.
