Motor Intention and Action Awareness – ConsciousBrain

In this project, we use an integrated methodological approach making use of (i) peri-operative recordings in patients undergoing brain surgeries; (ii) psychophysics in healthy subjects and patients with focal brain lesions; (iii) single pulse and theta burst transcranial magnetic stimulation in healthy subjects; and (iv) functional MRI in healthy subjects.

Four main results have been obtained

(1) We have identified a functional specificity of the dorsal premotor cortex which seems to mediate the process of veridical awareness in relation to the observation that this structure is the most commonly injured region in patients suffering from anosognosia for hemiplegia

(2) We have shown that the parietal regions triggering intentional responses when stimulated do not receive sensory signals.

(3) We have identified, in the precentral gyrus, complex sensorimotor representations for hand-mouth movements with high ethological value.

(4) Finally, we have shown that direct electrical stimulation produces its action locally and does not spread randomly in a meaningless jumble

The project is on schedule. Preliminary results will be confirmed and more preliminary observations will be studied in more details (e.g. connectivity)

Three papers have been published in relation to this project


1. Desmurget M, Richard N, Harquel S, Baraduc P, Szathmari A, Mottolese C, Sirigu A (2014) Neural representations of ethologically relevant hand/mouth synergies in the human precentral gyrus. Proc Natl Acad Sci U S A 111:5718-5722
2. Desmurget M, Song Z, Mottolese C, Sirigu A (2013) Re-establishing the merits of electrical brain stimulation. Trends Cogn Sci 17:442-449
3. Desmurget, M. (2013). «Searching for the neural correlates of conscious intention.« J Cogn Neurosci 25(6): 830-833

The sensorimotor system has been widely studied during the last decades, yet little is known about the neural substrate of high-level aspects of movement such as intention and awareness and how these are related to movement execution processes.
It has been proposed that the posterior parietal cortex and supplementary motor area are involved in generating motor intentions, while premotor cortex may play a key role in the emergence of motor awareness. However, the precise mechanisms implemented within each of these areas, the way they interact functionally and the nature of the signals they convey to primary sensory and motor regions is far from being understood. Ultimately, intention and awareness of movement are influenced by peripheral afferences coming from the eyes, skin, muscles and joints and this flow of information must be integrated to produce smooth, accurate and coordinated motor actions; but here again, little is known about the mechanisms that underlie this integration.

In this project we will investigate how the cortical regions responsible for attributing intention and bringing movement to consciousness share information, integrate sensory signals and update the course of actions. We will address these issues using an integrated methodological approach making use of (i) peri-operative recordings in patients undergoing brain surgeries; (ii) psychophysics in healthy subjects and patients with focal brain lesions; (iii) single pulse and theta burst transcranial magnetic stimulation in healthy subjects; and (iv) functional MRI in healthy subjects.

The close cooperation established between a research team specialized in sensorimotor neuropsychology (M Desmurget) and a neurosurgical group expert in peri-operative cerebral mapping (C Mottolese) provides a unique opportunity to carry out this ambitious research. Fundamental, clinical and societal outcomes are expected from this project. At a fundamental level, it should substantially improve our current understanding of the cerebral processes that mediate conscious intentions and motor awareness. At a clinical level, it should have a direct impact on the peri-operative mapping procedures used to minimize post-operative sequelae in patients with brain tumors. Also, it should provide a framework for understanding how abnormalities of conscious intention and action awareness can arise following acute or degenerative cerebral damages. Finally, at a societal level, this project should have major philosophical and ethical implications. In particular, it may contribute to reshape our approach of major societal issues such as personal merit or individual responsibility.