Hippocampal connectivity with sensorimotor cortex during volitional finger movements. II. Spatial and temporal selectivity

Abstract

AbstractCognitive control refers to brain processes involved in regulating behavior according to internal goals or plans. This study examines whether hippocampal connectivity with sensorimotor cortex during paced movements shows a pattern of spatial and temporal selectivity required for cognitive control. Functional magnetic resonance imaging activity was recorded from thirteen right-handed subjects during a paced, non-mnemonic (repetitive tapping) motor task. Connectivity was examined from psychophysiological interactions in hippocampal activity during two analyses: the first identified motor interactions relative to rest, whereas the second identified differential motor activity between adjacent fingers. Connectivity was observed in both pre- and postcentral gyrus, but only postcentral connectivity was topographical, coincident with finger representations identified in a previous study. Differences in the magnitude of connectivity were observed between finger representations, representing spatial selectivity for the target of movements; the postcentral representation of the moving finger invariably showed greater connectivity than adjacent fingers. Furthermore, the magnitude of connectivity within a pre- or postcentral finger representation was largest when its finger moved, representing temporal selectivity for movement. While the hippocampus is known to be sensitive to spatial and temporal features of the environment, consistent with its role in learning and memory, the pattern of spatial and temporal selectivity of hippocampal connectivity observed in this study occurred during volitional movements in the absence of motor learning or recall. Spatial and temporal selectivity of connectivity during volitional movements meets the criteria for cognitive control adapted from oculomotor studies, suggesting a role for the hippocampus in motor control.