Figure 4

Change of oxy-Hb level and sleep structures during the final 30 min before waking (n=11). Temporal change in the oxy-Hb level (A), the rate of oxy-Hb levels (B), and temporal change δ power in the prefrontal cortex (PFC) region (C) during the final 30 min before waking in 11 subjects. The “request” condition and oxy-Hb level (change according to time course and the rate during the final 30 min before waking) in the right PFC (rPFC) region gradually increased 20 min before predominant waking in the “success” group (black circle) compared with the “failure” group (○) (A-1, B-1). The delta power of the “success” group also decreased in the rPFC region with time under the request condition (C-1).