Neural dynamics of the intention to speak.
When we talk we communicate our intentions. Although the origin of intentional action is debated in cognitive neuroscience, the question of how the brain generates the intention in speech remains still open. Using magnetoencephalography, we investigated the cortical dynamics engaged when healthy subjects attended to either their intention to speak or their actual speech. We found that activity in the right and left parietal cortex increased before subjects became aware of intending to speak. Within the time window of parietal activation, we also observed a transient left frontal activity in Broca's area, a crucial region for inner speech. During attention to speech, neural activity was detected in left prefrontal and temporal areas and in the temporoparietal junction. In agreement with previous results, our findings suggest that the parietal cortex plays a multimodal role in monitoring intentional mechanisms in both action and language. The coactivation of parietal regions and Broca's area may constitute the cortical circuit specific for controlling intentional processes during speech.
Carota
Francesca
F
Center for Cognitive Neuroscience, Centre National de la Recherche de la Recherche Scientifique, Unité Mixte de Recherche 5229, 69675 Bron, France.
Posada
Andres
A
Harquel
Sylvain
S
Delpuech
Claude
C
Bertrand
Olivier
O
Sirigu
Angela
A
D001931:Brain Mapping; D002540:Cerebral Cortex / Q000033:anatomy & histology / Q000502:physiology; D005071:Evoked Potentials / Q000502:physiology; D056344:Executive Function / Q000502:physiology*; D005625:Frontal Lobe / Q000033:anatomy & histology / Q000502:physiology; D006801:Humans; D007802:Language; D007807:Language Tests; D015225:Magnetoencephalography; D009415:Nerve Net / Q000033:anatomy & histology / Q000502:physiology*; D009483:Neuropsychological Tests; D010296:Parietal Lobe / Q000033:anatomy & histology / Q000502:physiology; D017397:Prefrontal Cortex / Q000033:anatomy & histology / Q000502:physiology; D013060:Speech / Q000502:physiology*; D013702:Temporal Lobe / Q000033:anatomy & histology / Q000502:physiology; D014705:Verbal Behavior / Q000502:physiology*; D014836:Volition / Q000502:physiology*