Somatosensory dynamic gamma-band synchrony: a neural code of sensorimotor dexterity.

To investigate neural coding characteristics in the human primary somatosensory cortex, two fingers with different levels of functional skill were studied. Their dexterity was scored by the Fingertip writing test. Each finger was separately provided by a passive simple sensory stimulation and the responsiveness of each finger cortical representation was studied by a novel source extraction method applied to magnetoencephalographic signals recorded in a 14 healthy right handed subject cohort.

Functional source separation from magnetoencephalographic signals.

We propose a novel cerebral source extraction method (functional source separation, FSS) starting from extra-cephalic magnetoencephalographic (MEG) signals in humans. It is obtained by adding a functional constraint to the cost function of a basic independent component analysis (ICA) model, defined according to the specific experiment under study, and removing the orthogonality constraint, (i.e.