Magnetic responses to the stimuli. Superimposed waveforms of all 204 sensors recorded from one representative subject. A a, responses to the Standard, Test alone, Prepulse (30 ms) + Test, and Prepulse alone stimuli. A b, subtracted waveforms. Red and pink arrowheads indicate the onset of the Test and Prepulse, respectively. B), magnetic responses under the P50m sensory gating paradigm.