Karim Jerbi 26/11 16h
Large-scale brain dynamics of visuomotor and oculomotor behavior : Insights from MEG and intracerebral EEG recordings
INSERM U821, Brain Dynamics & Cognition, Lyon.
Local and long-distance neural synchonization play a key role in mediating sensorimotor behavior. Although neuroimaging studies continue to play a fundamental role in the study of large-scale perceptuo-motor networks, the fine-scale temporal and oscillatory properties of such networks need to be investigated with high (millisecond) temporal resolution. We will present data using invasive and non-invasive electrophysiological techniques that investigate oculomotor behavior and visuomotor control respectively. First, using Magnetoencephalography (MEG) we address the role of cerebral oscillations and long-range cortico-cortical coupling in mediating continuous visuomotor control. Beyond providing direct links between cortical activity and hand movement kinematics, our data reveal task-specific modulations of large-scale parieto-frontal activations across multiple frequency bands. In a separate study, we used stereotactic-EEG (SEEG) to record directly from various brain structures in implanted epilepsy patients while they performed a delayed saccade paradigm. The unique human intracranial findings we report suggest that high frequency activity in the gamma range (60-140 Hz) and long-range coupling (in alpha/beta range) might play a fundamental role in oculomotor planning as well as in a series of intricately related neural processes such as visuomotor transformation and visuo-spatial attention. Finally, we will discuss possible implications of our findings in the context of neural rehabilitation and brain computer interfaces.
INSERM U821, Brain Dynamics and Cognition, Le Vinatier, 69675 Bron Cedex