Sensory representations in the striatum provide a temporal reference for learning and executing motor habits

Area of Science:

• Neuroscience
• Motor Control
• Somatosensation

Background:

• The dorsolateral striatum (DLS) is known to integrate sensorimotor information for motor habit learning and execution.
• The specific role of sensory representations, particularly somatosensory input, in the DLS during this process remains unclear.

Purpose of the Study:

• To investigate the contribution of forelimb somatosensory pathways to the DLS during motor habit learning and execution.
• To elucidate the temporal dynamics of somatosensory processing in the DLS.

Main Methods:

• Comparison of rhythmic somesthetic representations in the DLS and primary somatosensory cortex in anesthetized rats.
• Behavioral protocol for developing stereotyped motor sequences in rats.
• Functional disconnection experiments, pharmacologic, and optogenetic manipulations in apprentice and expert animals.

Main Results:

• The DLS exhibits stronger representation of sequential and temporal somatosensory stimuli compared to the primary somatosensory cortex.
• Somatosensory thalamic- and cortical-striatal pathways are critical for the temporal aspects of motor habit execution.
• Disruptions to these pathways impair the temporal precision of learned motor sequences.

Conclusions:

• The somatosensory flow to the DLS is crucial for establishing the temporal framework of motor habits.
• This temporal reference provided by somatosensation is essential for both the development and precise execution of learned motor behaviors.