Lateralized rewarding brain stimulation affects forepaw preference in rats.

Area of Science:

• Neuroscience
• Behavioral Neuroscience
• Animal Behavior

Background:

• Paw preference in rats is a model for studying motor lateralization.
• The lateral hypothalamus is involved in motivation and reward.

Purpose of the Study:

• To investigate the role of lateral hypothalamic stimulation in modulating forepaw preference during a reaching task.
• To explore how motivational influences are lateralized in the brain.

Main Methods:

• Rats with established handedness were implanted with electrodes in the lateral hypothalamus.
• Intracranial self-stimulation (ICSS) was used as a reward for a reaching task.
• Lateralized ICSS was applied to assess its effect on forepaw preference.

Main Results:

• ICSS supported reaching behavior, with most rats adapting to delayed rewards.
• Stimulation of the lateral hypothalamus ipsilateral to the preferred forepaw increased the use of the non-preferred paw in latently ambidextrous rats.
• Contralateral stimulation did not alter paw preference.

Conclusions:

• Lateralized motivational influences can impact motor output asymmetry.
• The findings suggest that the lateral hypothalamus plays a role in the neural mechanisms underlying motor lateralization and preference.
• Brain lateralization of motivation influences motor control and sensory processing.