Changes in the site of appearance of nonspecific responses in the human EEG in normal subjects and in patients with focal damage

Summary

The zone in which the nonspecific response was manifested in the human EEG changed according to the nature of the stimuli and their sequence. The nonspecific response had a different distribution according to the modality of the first stimulus. Repeated photic stimuli produced a shift in the nonspecific response in the direction of the primary projection field of that stimulus. Nonspecific responses to sound may be shifted towards the zone of increased excitation created by rhythmic photic stimulation. The shift is particularly well shown in certain focal cerebral lesions. Thus in an extracerebral tumor and in some forms of intracerebral tumor of the parieto-occipital area, apart from the central zones the nonspecific response both to light and to sound was recorded at the pathological focus itself.