Functional tissue areas in a tissue region are located by illuminating the tissue by measurement illumination. Stimulation in the functional tissue areas leads to a change in at least one optical property of the reflected measurement illumination compared to the original measurement illumination. The functional tissue areas are located based on the change in the at least one optical property of the reflected measurement illumination by determining the difference between a stimulation image of the tissue region obtained during the stimulation and a comparison image of the tissue region obtained without stimulation. The difference may be formed from at least one image recorded with the measurement illumination and at least one image recorded without the measurement illumination to bring about an increase in contrast. An obtained image may be corrected on the basis of the determined topography of the tissue region to bring about an increase in contrast.
