Cortical reactivity in progressive XXXX .

@entity1 @entity16045 @entity28626 @entity3148
We studied 4 @entity1 with progressive @entity3148 ( @entity16045 ; @entity16045 ). Somatosensory evoked fields (SEFs), auditory evoked fields (AEFs), and spontaneous activity over the somatomotor cortex were recorded with a 24-channel SQUID gradiometer. All @entity1 had "giant" 20-45 msec median nerve SEFs at the first somatomotor cortex, with 2-6 times larger amplitudes than the healthy control subjects. Later deflections were not similarly enhanced. The dependence of @entity28626 amplitudes on interstimulus interval (0.2-4 sec) and on successive ulnar-median nerve stimulation (stimulus interval 40 msec) was comparable to that in controls. Cortical AEFs were attenuated and delayed. In 3 @entity1 , the spontaneous activity consisted of 6-8 Hz mu rhythm, which originated within 2 cm from the sources of SEFs and was abolished by clenching of the contralateral fist. Control subjects had major spectral peaks around 10 and 20 Hz. The @entity28626 amplitudes and the strength of the 6-10 Hz mu correlated strongly, suggesting that some components of evoked and spontaneous activity obtain contributions from overlapping neuronal populations. The results imply that @entity16045 is associated with thalamo-cortical hyperreactivity in the sensorimotor but not in the auditory system.
