RESISTANCE SHIFTS ACCOMPANYING EVOKED CORTICAL RESPONSE IN CAT

Clicks and flashes that evoke an electrical response from the auditory or visual cortex also evoke a resistance shift in the tissue. The resistance shift, a drop followed by a rise in resistance, closely follows the temporal pattern of the electrical response recorded simultaneously through the same electrodes. While several experimental manipulations produce corresponding changes in the amplitudes of both electrical response and resistance shift, the resistance shift is more sensitive to alterations in cortical temperature and anesthetic level. The two responses behave distinctly differently as a function of the depth of the electrode in the cortex.