Evoked potentials and simple motor reaction times to localized visual patterns.
Spatially localized, contrast modulated visual stimuli evoke a monophasic, inion negative scalp potential (VEP) which can be recorded simultaneously with motor responses in simple reaction time experiments. VEP response time and median motor response latency are linearly related over a wide range of stimuli. We interpret our results to suggest that VEPs and motor response latencies arise from a common sensory system with different thresholds for detection and reaction. A model is introduced to predict detection thresholds from VEP response times which are usually more robust measures than VEP amplitudes.
Hartwell
R C
RC
Department of Neurosurgery, University of Pennsylvania School of Medicine, Philadelphia 19104.
Cowan
J D
JD
D015350:Contrast Sensitivity / Q000502:physiology; D005074:Evoked Potentials, Visual / Q000502:physiology*; D006801:Humans; D010775:Photic Stimulation; D011930:Reaction Time / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology