Online repetitive transcranial magnetic stimulation (TMS) to the parietal operculum disrupts haptic memory for grasping


Cattaneo L; Maule F; Tabarelli D; Brochier T; Barchiesi G. Institution Cattaneo,Luigi. Center for Mind/Brain Sciences (CIMeC), Univer sity of Trento, Trento, Italy. Maule,Francesca. Center for Mind/Brain Sciences (CIMeC), Universit y of Trento, Trento, Italy. Tabarelli,Davide. Center for Mind/Brain Sciences (CIMeC), Univ ersity of Trento, Trento, Italy. Brochier,Thomas. Institut de Neurosciences de la Timone, UMR 7289, CNRS, Aix-Marseille Universite Marseille, France. Barchiesi,Guido. Center for Mind/Brain Sciences (CIMeC), Un iversity of Trento, Trento, Italy.


Online repetitive transcranial magnetic stimulation (TMS) to th e parietal operculum disrupts haptic memory for grasping.


Human Brain Mapping. 36(11):4262-71, 2015 Nov.

Abstract: The parietal operculum (OP) contains haptic memory on the geometr y of objects that is readily transferrable to the motor cortex bu t a causal role of OP in memory-guided grasping is only speculative. We explored this issue by using online high-frequency repetitive transcranial magnetic stimulation (rTMS). The experimental task was performed by blindfol ded participants acting on objects of variable size. Trials con sisted in three phases: haptic exploration of an object, delay, and reach-grasp movement onto the explored object. Motor performance was evaluated by th e kinematics of finger aperture. Online rTMS was applied to t he left OP region separately in each of the three phases of the task. The results showed that rTMS altered grip aperture only when applied in the delay phase to the OP. In a second experiment a haptic discriminative (match- to -sample) task was carried out on objects similar to those used in the first experiment. Online rTMS was applied to the left OP. No psychophysical effects were induced by rTMS on the detection o f explicit haptic object size. We conclude that neural activity in the OP region is necessary for proficient memory-guided haptic grasping. The fu nction of OP seems to be critical while maintaining the haptic memory trace and less so while encoding it or retrieving it.

Copyright © 2015 W iley Periodicals, Inc.

Publication Type: Journal Article.