Cortical plasticity in phantom limb pain: A fMRI study on the neural correlates of behavioral clinical manifestations.

Duarte D.; Bauer C.C.C.; Pinto C.B.; Saleh Velez F.G.; Estudillo-Guerra M.A.; Pacheco-Barrios K.; Gunduz M.E.; Crandell D.; Merabet L.; Fregni F. · Psychiatry Research - Neuroimaging (2020) · DOI: 10.1016/j.pscychresns.2020.111151

Resumen

The neural mechanism of phantom limb pain (PLP) is related to the intense brain reorganization process implicating plasticity after deafferentation mostly in sensorimotor system. There is a limited understanding of the association between the sensorimotor system and PLP. We used a novel task-based functional magnetic resonance imaging (fMRI) approach to (1) assess neural activation within a-priori selected regions-of-interested (motor cortex [M1], somatosensory cortex [S1], and visual cortex [V1]), (2) quantify the cortical representation shift in the affected M1, and (3) correlate these changes with baseline clinical characteristics. In a sample of 18 participants, we found a significantly increased activity in M1 and S1 as well as a shift in motor cortex representation that was not related to PLP intensity. In an exploratory analyses (not corrected for multiple comparisons), they were directly correlated with time since amputation; and there was an association between increased activity in M1 with a lack of itching sensation and V1 activation was negatively correlated with PLP. Longer periods of amputation lead to compensatory changes in sensory-motor areas; and itching seems to be a protective marker for less signal changes. We confirmed that PLP intensity is not associated with signal changes in M1 and S1 but in V1.

Instituciones: Universidad San Ignacio de Loyola