DISSECTING THE NEURAL MECHANISMS OF COGNITIVE CONTROL

Impulsivity is central to ADHD and implicated in disorders such as substance misuse, problem gambling, bipolar disorder, and borderline personality disorder. However its neural mechanisms remain poorly understood. In particular, it is unclear whether different forms of impulsivity reflect disruption of a single inhibitory process or represent distinct circuit-level dysfunctions with superficially similar behavioural outcomes.
Recent advances in mouse circuit neuroscience have highlighted the role of secondary motor cortex (M2), and in particular the anterolateral motor cortex (ALM), in action planning and execution. However the dynamics of neural activity in these regions has not yet been integrated into theories of impulsivity.
To address this question we have developed a novel head-fixed behavioural task capable of probing multiple dimensions of impulsivity. As mice performed this task we recorded neural activity in secondary motor and prefrontal cortex using neuropixel 2.0 probes.
Mice are able to perform a task in which trials requiring different forms of cognitive control are interleaved, including withholding premature responses and cancelling planned actions. Preliminary results suggest that a core component of cognitive control is effectively modulating the evolution of preparatory activity in secondary motor cortex along dimensions which encode movement initiation.
These results suggest that cognitive control may be best described not as a single inhibitory process, but as the result of multiple interacting circuit mechanisms.