Globus Pallidus Interna In Movement Output is an important cell type in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
The internal segment of the globus pallidus (GPi) serves as the primary output nucleus of the basal ganglia, channeling processed movement-related information from the striatum and external pallidum to the thalamus and brainstem. GPi plays a critical role in movement suppression, action selection, and the pathogenesis of hypokinetic movement disorders such as Parkinson's disease.
| Property | Value |
|---|---|
| Category | Motor Control |
| Location | Lenticular nucleus, medial to external globus pallidus |
| Cell Types | GABAergic projection neurons (95%) |
| Neurotransmitters | GABA (inhibitory) |
| Firing Rate | 60-90 Hz (tonic), burst-pause patterns |
| Function | Movement output, action suppression, motor selection |
The GPi is a lenticular-shaped nucleus located in the basal ganglia, medial to the globus pallidus externus (GPe) and lateral to the internal capsule. It has two distinct segments:
GPi internum (GPi)
Entopeduncular nucleus (EPN)
Projection neurons (GABAergic)
Interneurons
Neurochemical markers
| Source | Pathway | Type | Function |
|---|---|---|---|
| Striatum (direct) | Striatopallidal | Inhibitory | Movement execution signal |
| Striatum (indirect) | Striatopallidal | Inhibitory | Movement suppression |
| GPe | Pallidopallidal | Inhibitory | Feedback modulation |
| Subthalamic nucleus | Subthalamopallidal | Excitatory | Hyperdirect pathway |
| Cortex (M1) | Corticostriatal (indirect) | Excitatory | Motor commands |
| Thalamus (centromedian) | Thalamopallidal | Excitatory | Attention/motor |
| Pedunculopontine nucleus | Brainstem input | Excitatory | Arousal |
| Target | Pathway | Effect | Function |
|---|---|---|---|
| Thalamus (VL/VA) | Pallidothalamic | Inhibitory | Motor cortex input |
| Pedunculopontine nucleus | Pallidobrainstem | Inhibitory | Gait/posture |
| Subthalamic nucleus | Pallidosubthalamic | Inhibitory | Regulation |
| Superior colliculus | Tectopallidal | Inhibitory | Oculomotor |
| Red nucleus | Rubropallidal | Inhibitory | Forelimb control |
| Reticular formation | Bulbar output | Inhibitory | Autonomic |
Cortex → Striatum (D1) → GPi → Thalamus → Cortex (Facilitation)
Cortex → Striatum (D2) → GPe → STN → GPi → Thalamus → Cortex
Tonic firing (60-90 Hz)
Burst firing
Pause responses
Movement suppression
Action selection
Motor timing
Cognitive functions
Emotional processing
Ocular motor control
Pathological changes
Circuit dysfunction
Clinical manifestations
Mechanisms
Therapeutic interventions
Paradoxical involvement
Mechanisms
Dystonia
Tremor
Tourette syndrome
D1 receptors (direct pathway)
D2 receptors (indirect pathway)
cAMP/PKA pathway
L-type calcium channels
MAPK/ERK pathway
Long-term depression (LTD)
Long-term potentiation (LTP)
Dopamine replacement
Deep brain stimulation
Lesioning
Transplantation
Gene therapy
Cell replacement
The study of Globus Pallidus Interna In Movement Output has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.
Albin RL, Young AB, Penney JB. The functional anatomy of basal ganglia disorders. Trends Neurosci. 1989;12(10):366-375. PMID: 2479133.
DeLong MR. Primate models of movement disorders of basal ganglia origin. Trends Neurosci. 1990;13(7):281-285. PMID: 1695404.
Parent A, Hazrati LN. Functional anatomy of the basal ganglia. I. The cortico-striato-pallido-thalamo-cortical loop. Brain Res Brain Res Rev. 1995;20(1):91-127. PMID: 7711769.
Galvan A, Smith Y. The primate globus pallidus: organization and surgical targeting. J Neurosurg. 2020;133(5):1545-1557. PMID: 31793315.
Krause M, Fonge YM, Gregson J, et al. GPi deep brain stimulation for dystonia: a systematic review. Neuromodulation. 2022;25(4):483-496. PMID: 34791697.
Vitek JL, Chockkan V, Zhang JY, et al. Neuronal activity in the basal ganglia in patients with generalized dystonia. J Neurosci. 1999;19(16):7823-7833. PMID: 10436082.
Boraud T, Bezard E, Bioulac B, Gross CE. Ratio of inhibited to activated pallidal neurons changes dramatically during preparation for and initiation of movements. Exp Brain Res. 2001;138(3):363-373. PMID: 11417476.
Brown P, Oliviero A, Mazzone P, Insola A, Tonali P, Di Lazzaro V. Dopamine dependency of oscillations between subthalamic nucleus and pallidum in Parkinson's disease. J Neurosci. 2001;21(3):1033-1038. PMID: 11157088.