title: Task-related gamma-band dynamics from an intracerebral perspective: review and implications for surface EEG and MEG.
abstract: Although non-invasive techniques provide functional activation maps at ever-growing spatio-temporal precision, invasive recordings offer a unique opportunity for direct investigations of the fine-scale properties of neural mechanisms in focal neuronal populations. In this review we provide an overview of the field of intracranial Electroencephalography (iEEG) and discuss its strengths and limitations and its relationship to non-invasive brain mapping techniques. We discuss the characteristics of invasive data acquired from implanted epilepsy patients using stereotactic-electroencephalography (SEEG) and electrocorticography (ECoG) and the use of spectral analysis to reveal task-related modulations in multiple frequency components. Increasing evidence suggests that gamma-band activity (>40 Hz) might be a particularly efficient index for functional mapping. Moreover, the detection of high gamma activity may play a crucial role in bridging the gap between electrophysiology and functional imaging studies as well as in linking animal and human data. The present review also describes recent advances in real-time invasive detection of oscillatory modulations (including gamma activity) in humans. Furthermore, the implications of intracerebral findings on future non-invasive studies are discussed.
authors.affiliation: INSERM U821, Brain Dynamics and Cognition; Université Claude Bernard, Lyon 1, Lyon, France.
authors.forename: Karim
authors.initials: K
authors.lastname: Jerbi
authors.forename: Tomás
authors.initials: T
authors.lastname: Ossandón
authors.forename: Carlos M
authors.initials: CM
authors.lastname: Hamamé
authors.forename: S
authors.initials: S
authors.lastname: Senova
authors.forename: Sarang S
authors.initials: SS
authors.lastname: Dalal
authors.forename: Julien
authors.initials: J
authors.lastname: Jung
authors.forename: Lorella
authors.initials: L
authors.lastname: Minotti
authors.forename: Olivier
authors.initials: O
authors.lastname: Bertrand
authors.forename: Alain
authors.initials: A
authors.lastname: Berthoz
authors.forename: Philippe
authors.initials: P
authors.lastname: Kahane
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Lachaux