Influence of different half-field stimulations on the pattern reversal visually evoked cortical potential.

In 30 healthy subjects the visually evoked cortical potential following full-field and upper, lower, temporal and nasal half-field pattern-reversal stimulation was registered. No significantly differing latencies for peak N90 were to be seen. The responses of peak P120 for upper half-field stimulation showed a significantly longer latency than for full-field, lower, temporal and nasal half-field stimulation. Responses to upper and lower half-field stimulation showed no potential reversal. Nasal and temporal half-field stimulation evoked responses with no significantly differing P120 latencies.