Sensory modality of initiation cues modulates action goal-relevant neural representations.

The ability to produce goal-directed movement relies on the integration of diverse sensory cues which contribute to goal subtasks, such as trajectory planning and initiation. To achieve these subtasks, the central nervous system must flexibly weight sensory contributions depending on task context, and sensory cues from one modality may contribute to multiple subtasks. Neural representations of goal-relevant features are flexible to a variety of sensory contexts. It remains less clear how neural representations of goal-relevant features are modulated when initiation-relevant features rely on sensory cues from overlapping sensory modalities. We used Bayesian pattern component modeling of fMRI data during a delayed reach task with either visual or audiovisual go-cues to explore whether neural representations of goal-related features in sensorimotor areas are modulated by changes to initiation-relevant sensory information. We found that representations of gaze direction and target direction in the primary sensory areas, motor areas, and posterior parietal cortex varied depending on whether a reach was cued with a visual or audiovisual go-cue. These findings suggest that the central nervous system flexibly delegates the tasks of 'where' to move and 'when' to move based on available sensory context, even if initiation-relevant stimuli provide no additional information about target location.