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Updated: May 10, 2026
12:33
Corticospinal Excitability Modulation During Action Observation
Published on: January 1, 2014
Concurrent activation of striatal direct and indirect pathways during action initiation
Guohong Cui1, Sang Beom Jun, Xin Jin
1Section on In Vivo Neural Function, Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland 20892-9412, USA.
Nature
|January 29, 2013
Summary
Researchers developed a new method to measure neural activity in the basal ganglia. This study challenges the traditional view of how the direct and indirect pathways control movement.
Area of Science:
- Neuroscience
- Motor Control
- Basal Ganglia Function
Background:
- The basal ganglia are crucial for voluntary movement control.
- Current models propose opposing roles for direct and indirect pathways in motor control.
- Testing these models in freely moving animals has been challenging.
Purpose of the Study:
- To develop a novel in vivo method for selectively measuring direct- and indirect-pathway spiny projection neuron (SPN) activity.
- To investigate the activity patterns of these pathways during voluntary action initiation.
Main Methods:
- Utilized Cre-dependent viral expression of GCaMP3 in D1-Cre and A2A-Cre mice.
- Employed fiber optics and time-correlated single-photon counting (TCSPC) in freely moving mice.
- Monitored neural activity during an operant conditioning task.
Main Results:
- Observed transient increases in neural activity in both direct- and indirect-pathway SPNs upon action initiation.
- Found concurrent activation of both pathways preceded contraversive movements.
- Neural activity predicted specific movements within 500 ms.
Conclusions:
- Findings challenge the classical model of opposing direct and indirect pathway functions.
- Suggests a more complex interplay between basal ganglia pathways in motor control.
- May offer new insights into neurological disorders affecting the basal ganglia.
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