Abstract
Controlling direction of locomotion is fundamental to all mobile animals, and it is particularly critical for humans, whether as pedestrian or in vehicles. At ECVP 2006 Field, Wilkie & Wann presented an fMRI study exploring the neural correlates of human heading judgments and the equivalence to areas identified in macaques, including the ventral intraparietal area (VIP). Furthermore, we illustrated how the presence of a visible path, providing heading error information, activated bilateral regions focused on, but not exclusive to, parietal eye fields (LIP, although other cortical eye fields were not selectively activated by the pathway). Here we focus on how these regions are engaged when participants are actively steering over a textured ground plane to keep within the bounds of a roadway. The anterior portion of our parietal region of interest became more active when steering errors occurred, and the steering task also engaged bilateral areas of the cerebellum, left dominant dorsal premotor cortex, and supplementary eye fields (SEF). While the SEF activation was due to the eye-movements occurring during active steering, a saccade task and fixation conditions were used to exclude eye-movements as the primary factor in the activations observed in other key areas.
Supported by the UK EPSRC