Isolation of Distinct Networks Driving Action and Cognition in Psychomotor Processes

Background Psychomotor disturbances are observed across psychiatric disorders and often present as psychomotor slowing, agitation, disorganized behavior, or catatonia. Psychomotor function includes both cognitive and motor components, but the neural circuits driving these subprocesses and how they relate to symptoms have remained elusive for centuries. Methods We analyzed data from the Human Connectome Project for Early Psychosis, a multi-site study of 125 people with early psychosis and 58 healthy participants with resting-state fMRI and clinical characterization. Psychomotor function was assessed using the 9-Hole Pegboard Task, a timed motor task which engages mechanical and psychomotor components of action, and tasks assessing processing speed and task switching. We used multivariate pattern analysis of whole-connectome data to identify brain correlates of psychomotor function. Results We identified discrete brain circuits driving the cognitive and motor components of psychomotor function. In our combined sample of psychosis patients (n=89) and non-psychiatric controls (n=52), the strongest correlates of psychomotor function (pegboard performance) (p<.005) were between a midline cerebellar region and (1) left frontal region and (2) pre-supplementary motor area (preSMA). Psychomotor function was correlated with both cerebellar-frontal connectivity (r=0.33) and cerebellar-preSMA connectivity (r=0.27). However, the cognitive component of psychomotor performance (task-switching) was only correlated with cerebellar-frontal connectivity (r=0.19), whereas the motor component (processing speed) was only correlated with cerebellar-preSMA connectivity (r=0.15), suggesting distinct circuits driving unique subprocesses of psychomotor function. Conclusions We identified cerebellar-cortical circuits that drive distinct subprocesses of psychomotor function. Future studies should probe relationships between cerebellar connectivity and psychomotor performance using neuromodulation.