The silent cortex revisited: Multimodal evidence for a reorganisation in the hand region of the primary somatosensory cortex in hand amputation and hand dysmelia

Amputation as well as dysmelia is known to induce a reorganisation of the primary somatosensory cortex (SI). This reorganisation is reflected in a reduced or increased amount of neurons in SI representing the affected part of the body surface. Moreover, the amount of reorganisation in SI was shown to be strongly correlated with dysfunctional effects like phantom pain. While animal studies allow for a direct measurement of the extent of the deafferented areas in SI, studies in humans with phantom pain or dysmelia used rather indirect measures like interhemispheric differences of distances in SI. Thus, little is k…