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Updated: Jul 15, 2026
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High-resolution Functional Magnetic Resonance Imaging Methods for Human Midbrain
Published on: May 10, 2012
Globus pallidus external segment.
1Department of Anatomy and Neurobiology, The University of Tennessee Memphis, 855 Monroe Avenue, Memphis, TN 38163, USA. hkita@utmem.edu
Progress in Brain Research
|May 15, 2007
Summary
The external pallidum (GP(e)) is a central basal ganglia nucleus receiving inputs from the striatum and subthalamic nucleus. It plays a key role in the indirect pathway, relaying information to the subthalamic nucleus.
Area of Science:
- Neuroscience
- Basal Ganglia Research
Background:
- The external segment of the pallidum (GP(e)) is a crucial nucleus within the basal ganglia.
- It is anatomically positioned caudomedial to the neostriatum (Str).
Purpose of the Study:
- To describe the anatomical organization of the GP(e).
- To characterize the physiological and pharmacological properties of GABAergic responses within the GP(e).
Main Methods:
- Anatomical tracing and description of the GP(e).
- Physiological and pharmacological studies focusing on GABAergic neurotransmission.
Main Results:
- The GP(e) receives major inputs from the striatum (Str) and subthalamic nucleus (STN).
- The GP(e) projects to multiple basal ganglia nuclei, including the STN, Str, internal pallidal segment (GP(i)), and substantia nigra (SN).
- The GP(e) functions as a component of the basal ganglia's indirect pathway, relaying striatal inputs to the STN.
Conclusions:
- The GP(e) is centrally located in basal ganglia circuitry.
- Understanding GP(e) GABAergic responses is vital for comprehending basal ganglia function in motor control and other processes.
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