Poster E3, Saturday, August 18, 3:00 – 4:45 pm, Room 2000AB
Is the Ventrolateral Prefrontal Cortex language-specific or domain-general? An intracranial-EEG study
Marcela Perrone-Bertolotti1, Samuel El Bouzaïdi Tiali1, Richard Palluel-Germain1, Lorella Minotti2,3,4, Anne-Sophie Job2,3,4, Philippe Kahane2,3,4, Monica Baciu1, Jean-Philippe Lachaux5,6;1Univ. Grenoble Alpes, CNRS, LPNC UMR 5105, 38000, Grenoble, France, 2Univ. Grenoble Alpes, Institut des Neurosciences, GIN, 38000 Grenoble, France, 3CHU Grenoble Alpes, Pôle Neurologie Psychiatrie, 38000, Grenoble, France, 4INSERM, U1216, F-38000, Grenoble, France, 5INSERM, U1028, CNRS, UMR5292, Lyon Neuroscience Research Center, Brain Dynamics and Cognition Team, DYCOG, Lyon F-69000, France, 6Lyon’s University, Lyon, France
A broader functional role of Broca's area (i.e., the left ventrolateral prefrontal cortex –VLPFC- including the BA 45A and 45B from Petrides and Pandya, 2002) has been suggested by recent neuroimaging studies. According to findings, VLPFC would mediate integrative non-linguistic processes that are useful for language (e.g., Tate et al., 2014; Nazori & Thompson-Shill, 2016; Novick et al., 2009). In this framework, our present study aim at evaluating the role of the VLPFC and the time-course of its activity within cerebral networks related to a set of linguistic and non-linguistic tasks. We also evaluated the dynamic relation between the VLPFC and core language regions. We explored cerebral activity of patients suffering from refractory epilepsy during their pre-chirurgical intracranial-EEG recording and we specifically focused on the High Frequency Activity (HFA 50–150 Hz) as a proxy of population-level spiking activity (Lachaux et al., 2012). Patients performed five cognitive tasks: i) single words semantic and phonological categorization, ii) attentive sentence reading, iii) delayed matched-to-sample, iv) visual search and v) visual target detection. Our results showed a VLPFC activity across the five tasks in line with results suggesting a broader functional role of this region. During reading, VLPFC present an early strong response (between 200-300ms after stimulus onset) just after the visual word processing (in the ventral occipitotemporal cortex around 150-200ms) and before the responses in core language regions (such as the superior temporal gyrus, the middle posterior temporal gyrus and the opercularis pars of the inferior frontal gyrus in which responses were observed between 300-550ms). Overall, our results suggest VLPFC involvement during the early stage of language comprehension. A possible role of this region could be involved in decision to process an incoming stimulus and to trigger a cascade of high-level processes by top-down activity. Our results point out that the VLPFC function is not restricted to the language domain, in line with other studies suggesting that the VLPFC is a critical part of the domain general network related to cognitive control.
Topic Area: Control, Selection, and Executive Processes