The Effects of Electrical Microstimulation on Cortical Signal Propagation

Nikos K Logothetis (1) , Mark A Augath (1) , Yusuke Murayama (1) , Alexander Rauch (1) , Fahad F Sultan (1) , Jozien Goense (1) , Axel Oeltermann (1) , Hellmut Merkle (1)

1 Physiology of Cognitive Processes

This study used combined electrostimulation, neurophysiology, microinjection and fMRI to investigate the cortical activity patterns elicited during stimulation of cortical afferents in monkeys. We found that stimulation of a site in LGN (lateral geniculate nucleus) increases the fMRI signal in the regions of primary visual cortex (V1) receiving input from that site, but suppresses it in the retinotopically matched regions of extrastriate cortex. In agreement with previous observations, intracranial recordings showed that immediately after a stimulation pulse a short excitatory response is followed by long-lasting inhibition. Following microinjections of GABA (γ-aminobutyric acid) antagonists in V1, LGN stimulation induced positive fMRI signals in all cortical areas. Taken together, our findings suggest that ES disrupts cortico-cortical signal propagation by silencing the output of any neocortical area whose afferents are electrically stimulated.

Mots clés: Neurophysiology; Sensory Systems; Neuroimaging; Neurovasculature; Neuroscience; Biophysics

Nikos K Logothetis, Mark A Augath, Yusuke Murayama, Alexander Rauch, Fahad F Sultan, et al.. The Effects of Electrical Microstimulation on Cortical Signal Propagation. Nature Neuroscience, 2010, ⟨10.1038/nn.2631⟩. ⟨hal-00573858⟩