Figure 8From: Morphine modulation of pain processing in medial and lateral pain pathways Partial directed coherence (PDC) among different brain regions induced by noxious stimuli before (A) and after (B) injection of morphine. The PDC values were normalized to z-scores relative to the mean and variance of baseline PDC (i.e., before noxious stimulation). The normalized PDCs exceeding 95% confident interval of the baseline were displayed in pseudo color (yellow and red for the increase and cyan and blue for the decrease). Arrows indicate the direction of information flow. (A) Before morphine injection, the amount of directed coherence from medial to lateral pathway significantly increased with a latency of 0.5 sec. (B) No significant change was observed in the PDC following morphine administrationBack to article page