Biomedical subjects
Publications and source records attributed to R S Vera.
We have developed a system to generate from 16 channels of the EEG 3-dimensional sequential topographical displays that facilitate the analysis of the propagation and field distribution of paroxysmal discharges. The ease and flexibility of data storage and analysis is as important as the concept of representing the EEG field potentials in a comprehensible fashion.
This automated system detects spikes when the first derivative value of the EEG or ECoG signal exceeds a user-determined threshold twice, with reversal of direction, within 30--80 msec. The EEGer selects this threshold by his assessment of the system's initial performance in a recording situation. By combining the spike detecting abilities of both the EEGer and computer, two tasks can be accomplished on-line for 16-channel EEG or ECoG: (1) localization of the origin of widely synchronous spikes, and (2) assessment of the relative quantities of spikes emanating from several active regions. This system achieved a human-computer correlation ranging from 0.79 to 0.84.