Figures & data
Figure 1 MRS of ACC was recorded at rest and during painful skin heat stimulation before and 80 minutes after drug administration in a randomized, double-blind, cross-over study using orally administered morphine (30 mg) or placebo. Heat was applied using a contact heat-evoked potential stimulator (CHEPS) for 5 minutes with a destination temperature found prior to the scan (maximum 45°C) and the starting temperature was 32°C. Subjective pain perception of the stimulus was rated.
Figure 2 The voxel of interest was placed in the midline in the pregenual anterior cingulate cortex with the inferior border along the anterior-posterior commissure line. An example of the metabolite spectrum is shown, along with peaks for the analyzed metabolites.
Table 1 Overview of the means ± standard deviations of quality measurements (full width at half maximum, signal-to-noise ratio, Cramér-Rao), pain ratings, and metabolite concentrations in the anterior cingulate cortex
Figure 3 Creatine concentration (A) and metabolite ratios (ratio, no unit) (B) at rest (gray) and during painful stimulus before treatment (black). *P<0.05.
Figure 4 NAA/creatine for each subject during rest and painful stimulation before and during treatment with morphine (A) and placebo (B).
