Structural and functional variability of the dorsal premotor region involved in writing (Exner’s Area)

The so-called Exner’s area, located in the posterior part of the left superior frontal gyrus in right-handers, is assumed to code for writing movements. Damage to Exner’s area can lead to slow and laborious writing in the absence of other cognitive, linguistic or motor deficits (pure agraphia). In brain imaging studies, Exner’s area is also reliably activated in writing tasks. This suggests that this part of the cortex acquires functional specificity for writing due to intensive training in childhood.
We will use structural and functional MRI data. We will aim at better characterizing the variability of the pattern of cortical folding in Exner’s area, and we will relate it to variability in the position of activations in a writing task. This approach will be applied to MRI data of adults and of children aged 8 to 11 years old. The methods used will draw on recent approaches based on machine learning (ISOMAP applied to cortical sulci [1]). They will rely on a representation if the cortical surface that is consistent between subjects as in [2].

[1] Z. Y. Sun, P. Pinel, D. Rivière, A. Moreno, S. Dehaene, J.-F. Mangin, Linking morphological and functional variability in hand movement and silent reading, Brain Structure and Function, 221 (7), 3361-3371, 2016
[2] C. Bodin, S. Takerkart, P. Belin, O. Coulon, Anatomo-functional correspondence in the superior temporal sulcus, Brain Structure and Function, in press, 2017

marieke.longcamp@univ-amu.fr or julien.lefevre@univ-amu.fr

Share the offer on :