The pontine substrate of circling behavior

Area of Science:

• Neuroscience
• Behavioral Neuroscience
• Electrophysiology

Background:

• Circling behavior can be elicited by brainstem stimulation.
• The precise neural substrates within the pons responsible for circling behavior remain incompletely understood.

Purpose of the Study:

• To identify and characterize the pontine neural substrates that, when stimulated, elicit circling behavior in rats.

Main Methods:

• Movable stimulating electrodes were implanted in 9 rats.
• Electrical stimulation was applied to various brain sites within the pons.
• The effectiveness of stimulation was determined by measuring rotation speed and required pulse period.

Main Results:

• Out of 387 stimulated sites, 166 elicited ipsiversive rotation.
• The circling substrate was located in the medial pontine reticular formation.
• The positive region extended ventrally and laterally from the midline.

Conclusions:

• The pontine substrate for circling behavior is a large, sagittally oriented bundle within the medial reticular formation.
• This finding contributes to understanding the neural control of coordinated motor behaviors.