Kyoto University Researchers Identify Neural Circuits Governing Habit Formation in Mice

Understanding Habit Formation

Habit formation involves the transition from deliberate to automatic decision-making, where repeated behaviors become routine. While the necessity of repetition for habit formation is established, it has been unclear whether habits are exact replications or if behaviors change as they become habitual. The long duration of habit formation in humans makes it difficult to track behavioral and neural changes within the same subject.

New Research Method

A team at Kyoto University, including Nozomi Asaoka, Diane Pagano, and Yasunori Hayashi, developed a new training method that achieves rapid habit formation in mice. This method allowed them to directly track the transitions from goal-directed to habitual behavior in individual mice, overcoming previous research challenges.

Identification of Neural Circuits

The research identified two distinct neural circuits responsible for different aspects of habits. The first circuit, involving neurons from the anterior cingulate cortex to the retrosplenial cortex, determines whether a behavior becomes a habit, with its connections weakening during the transition. The second circuit, from the lateral orbitofrontal cortex to the central striatum, controls the extent to which a habit is executed, explaining individual differences in behavioral performance. Mice with strong neural responses in this second circuit maintained high execution levels, while those with weaker responses showed reduced execution.

Implications for Habit Control

By artificially manipulating these identified pathways, the team was able to selectively promote habit formation. This discovery contributes to understanding how habits work, potentially leading to future methods for controlling habits in humans.