Summary: A new study reveals that habit formation is managed by two distinct neural circuits, one governing the initiation of a habit and another controlling the intensity and frequency of its execution.
The research utilized a novel accelerated training protocol in mice to observe the real-time neural transition from goal-directed actions to automatic habits. The findings show that connections between the anterior cingulate cortex and retrosplenial cortex weaken to allow habit formation, while projections from the lateral orbitofrontal cortex to the central striatum dictate how strongly that habit is expressed. This discovery explains individual variance in habit strength and highlights new target pathways for treating compulsive conditions like obsessive-compulsive disorder.
Key Facts
- Accelerated Rapid Training Protocol: Kyoto University researchers developed a specialized two-stage behavioral training regimen that enabled rapid habit induction in mice within four days, permitting direct intra-subject mapping of pre- and post-habit neural transitions.
- Circuit 1 (Habit Gatekeeper): Neurons projecting from the anterior cingulate cortex (ACC) to the retrosplenial cortex (RSC) dictate whether a goal-directed behavior transitions into a habit; functional connectivity within this circuit systematically weakens as automaticity takes over.
- Circuit 2 (Execution Regulator): Projections extending from the lateral orbitofrontal cortex (lOFC) to the central striatum (CS) govern the behavioral volume and frequency of habit execution, driving individual differences in how strongly a habit is performed.
- Bidirectional Pathway Manipulation: By artificially stimulating or suppressing these pathways, the research team successfully induced habit formation or altered execution volume on demand, confirming distinct circuit roles.
- Clinical Significance for Compulsive Disorders: Decoding why habit strength varies individually provides a circuit-level foundation for understanding and treating maladaptive habits in psychiatric conditions like obsessive-compulsive disorder (OCD) and addiction.
Source: Kyoto University
Habit formation describes the repeated performance of a behavior until it becomes routine: in other words, the shift from deliberate to automatic decision-making. This concept is often invoked as a way to improve one’s life by making a routine of beneficial activities that can otherwise feel tedious, such as cleaning, studying, and regular exercise.
That repeating the same behavior is essential for forming a habit has become well-established, but whether a habit develops as an exact replication of the original behavior, or if the behavior itself gradually changes as it becomes a habit, remains unclear. Because habit formation takes a long time, comparing behavioral and neural changes within the same subject before and after a habit develops has been difficult.
To overcome this challenge, a team of researchers at Kyoto University developed a new training method that achieves rapid habit formation in mice, allowing them to track these transitions directly.
“Habits are one of the brain’s most mysterious functions, and we often struggle to control them even though they are our own actions,” says co-corresponding author Nozomi Asaoka. “By uncovering how habits work, we may eventually find ways to take control of them rather than letting them control us.”
Just like how humans develop habits, the team first trained subject mice to use goal-directed strategies, followed by an additional four-days of training designed to facilitate the adoption of habitual strategies. With this two-stage training approach, the researchers were able to assess the transition from goal-directed to habitual behavior in the brains of individual mice.
The team discovered that two distinct neural circuits manage completely different aspects of habits. The first circuit, with neurons projecting from the anterior cingulate cortex to the retrosplenial cortex, determines whether a behavior becomes a habit, with its connections weakening during the transition. Crucially, the second circuit, from the lateral orbitofrontal cortex to the central striatum, controls how much the habit is executed, explaining individual differences.
In this second circuit, habit-formed mice with strong neural responses maintained high behavioral execution levels, while those with weaker responses showed reduced execution. By artificially manipulating these pathways, the team was able to selectively promote habit formation or alter execution levels, proving the distinct roles of these two brain circuits.
One key finding is that the habit formation process is much more complex than the traditional view that repetition simply replicates an action into a habit in its original form. In particular, the team demonstrated that even after a habit successfully forms, there are significant individual differences in the frequency and volume of that behavior.
“Our study has uncovered previously overlooked control mechanisms involved in habit formation, showing what determines how strongly a habit is carried out and helping explain why habits differ from person to person,” says team leader Yasunori Hayashi.
The team plans to expand their investigations to find out what drives these individual differences in habit intensity, hoping that better understanding may help us acquire more beneficial habits and improve treatment for problematic habits linked to conditions such as obsessive-compulsive disorder.
Key Questions Answered:
A: Goal-directed behavior involves deliberate, conscious decision-making driven by specific outcomes. Habitual behavior represents a shift toward automatic execution that occurs routinely without requiring continuous conscious evaluation of outcomes.
A: The first circuit (anterior cingulate cortex to retrosplenial cortex) acts as a switch, determining whether an action becomes a habit by weakening its connections. The second circuit (lateral orbitofrontal cortex to central striatum) acts as a volume knob, dictating how frequently and intensely that formed habit is executed.
A: By pinpointing the specific circuit responsible for habit execution intensity (the lOFC to central striatum pathway), scientists can develop targeted therapies to down-regulate hyperactive habit execution without disrupting basic goal-directed learning.
Editorial Notes:
- This article was edited by a Neuroscience News editor.
- Journal paper reviewed in full.
- Additional context added by our staff.
About this habit formation and OCD research news
Author: Whitney Hubbell
Source: Kyoto University
Contact: Whitney Hubbell – Kyoto University
Image: The image is credited to Neuroscience News
Original Research: Open access.
“Dissociable roles of prefrontal plasticity in decision making strategy and execution of habitual behavior” by Nozomi Asaoka, Diane Pagano & Yasunori Hayashi . Nature Communications
DOI:10.1038/s41467-026-75706-1
Abstract
Dissociable roles of prefrontal plasticity in decision making strategy and execution of habitual behavior
Habits are essential for sustaining adaptive behaviors but can also lead to maladaptive behaviors such as compulsive and addictive disorders. They emerge through a shift in decision-making from motivation-driven strategy to an automatic one.
During this, the level of habit execution, such as frequency and duration, is superficially maintained despite a decline in motivational drive, raising the question of how the amount of execution is maintained even when decision-making strategies undergo substantial changes.
By developing a unique paradigm capable of inducing habit formation within a defined time window in male mice, we found that shift in decision-making and amount of habit execution are controlled by plasticity in distinct cortical pathways.
Erasure of each plasticity selectively altered the decision-making strategy or the execution level without affecting the other. These findings reveal a dual regulatory model for habit, providing insights into the neurocircuit mechanisms underlying both adaptive and maladaptive habits.
