Fig. 5.

The spreading depolarization (SD) phenomenon as assessed at a single recording site by direct current (DC) potential recording (black trace) and alternating current (AC)-electrocorticography (gray trace); and two distinct types of associated CBF response (red trace) acquired by laser Doppler flowmetry. Representative traces are original recordings from the rat brain. SD was elicited by the topical application of high-concentration K⁺ in the young intact (A) and the old ischemic (B) parietal cortex.