No abstract

No abstract

AcknowledgmentsThis study was supported by grants from Japan Science and Technology Corporation under the ERATO and CREST schemes. We thank Richard Henson, Okihide Hikosaka, Hiroshi Imamizu, Mitsuo Kawato, and Hiroyuki Nakahara for helpful comments and Alex Harner for the experimental software. We thank anonymous reviewers for their suggestions for improving the manuscript. We thank Joe Gati, for the help in running the experiments and V. S. Chandrasekhar Pammi and Ahmed, UH for help with analysis. ABSTRACTA visuomotor sequence can be learned as a series of visuo-spatial cues or as a sequence of effector movements. Earlier imaging studies have revealed that a network of brain areas is activated in the course of motor sequence learning. However these studies do not address the question of the type of representation being established at various stages of visuomotor sequence learning. In an earlier behavioral study, we demonstrated that acquisition of visuo-spatial sequence representation enables rapid learning in the early stage and progressive establishment of somato-motor representation helps speedier execution by the late stage. We conducted functional magnetic resonance imaging (fMRI) experiments wherein subjects learned and practiced the same sequence alternately in normal and rotated settings. In one rotated setting (visual), subjects learned a new motor sequence in response to an identical sequence of visual cues as in normal. In another rotated setting (motor), the display sequence was altered as compared to normal, but the same sequence of effector movements were used to perform the sequence. Comparison of different rotated settings revealed analogous transitions both in the cortical and subcortical sites during visuomotor sequence learning  a transition of activity from parietal to parietalpremotor and then to premotor cortex and a concomitant shift was observed from anterior putamen to a combined activity in both anterior and posterior putamen and finally to posterior putamen. These results suggest a putative role for engagement of different cortical and subcortical networks at various stages of learning in supporting distinct sequence representations.

No abstract

How do in-vehicle telematics devices influence mind-onthe-drive? We determined the spatio-temporal properties of the brain mechanisms during a simple visual event detection and motor response in a validated driving-like protocol. We used the safe and non-invasive brain imaging methods of functional magnetic resonance imaging (fMRI) and Magnetoencephalography (MEG) to locate the essential brain activated structures and their corresponding temporal dynamics. This study sets the foundation for determining the fundamental brain mechanisms by which secondary tasks (such as cell phone use) may affect the responses to visual events in a laboratory setting. Improved knowledge of the brain mechanisms underlying selective attention in such driving-like situations may give rise to methods for improving mind-on-the-drive.