Functional properties of striatal fast-spiking interneurons

Area of Science:

• Neuroscience
• Motor Control
• Computational Neuroscience

Background:

• Striatal fast-spiking interneurons (FSIs) are crucial for motor control, influencing behavioral output.
• Deficits in FSIs are implicated in neurological conditions like dystonia and Tourette syndrome.
• Previous knowledge of FSI activity in behaving animals was limited.

Purpose of the Study:

• To investigate the activity patterns of striatal FSIs in behaving rodents.
• To understand the role of FSI activity in action selection and execution.
• To explore FSI involvement in striatal oscillations and their relation to reward and drugs.

Main Methods:

• Electrophysiological recordings of FSI activity in awake, behaving rodents.
• Analysis of FSI firing rates, spike timing variability, and oscillatory activity.
• Correlation of FSI activity with specific behavioral tasks, including action initiation and suppression.

Main Results:

• Striatal FSIs exhibit near-continuous activity in awake rodents, though neighboring cells are often uncorrelated.
• A coordinated pulse of increased FSI firing accompanies action initiation, coinciding with reduced globus pallidus activity.
• FSI spike timing variability decreases after instruction cues, and they participate in behavior-linked striatal oscillations.

Conclusions:

• Striatal FSIs play a significant role in coordinating action execution through synchronized firing and pallidostriatal disinhibition.
• FSI activity modulation, including spike timing and oscillations, is linked to behavioral cues, reward, and dopaminergic drugs.
• These findings provide novel insights into striatal information processing in both healthy and diseased states.