Magnetic field responses to visual stimulation in human parietal association cortex.

The neural activities of the parietal association cortex were studied in humans through the use of a 37-channel SQUID magnetometer system. The magnetic field responses were recorded in the parietal association cortex following visual stimulation with LED light. Main responses peaking at about 120, 170 and 220 msec after LED onset were observed. The estimated current dipole sources of the magnetic field responses at latencies of 160-190 and 210-270 msec were revealed to be located in the intraparietal sulcus. A change in the magnetic field responses with the eye position was found in the amplitude.