Positron emission tomographic analysis of cerebral structures activated specifically by repetitive noxious heat stimuli

摘要: 1. To identify the forebrain and brain stem structures that are active during perception of acute heat pain in humans, we performed H2 15O positron emission tomographic (PET) analyses cerebral blood flow (CBF) on nine normal volunteers while they received repetitive noxious (50 degrees C) innocuous (40 5 s pulses to forearm (average resting temperature 31.8 C). Each subject rated subjective intensity each stimulation series according a magnitude estimation procedure which 0 = no sensation, 7 barely painful, 10 tolerable. 2. Three scans were at temperature. Mean CBF images created for experimental condition oriented onto standardized stereotaxic coordinates. Subtraction between conditions averaged across subjects. Volumes interest (VOI) chosen, based priori hypotheses results previously published PET studies. In addition, separate statistical summation analysis individual voxels was performed. Statistical thresholds established with corrections multiple comparisons. 3. Significant increases 50 C stimuli found contralateral thalamus, cingulate cortex, S2 S1 insula. The ipsilateral cortex medial dorsal midbrain cerebellar vermis also showed significant increases. All subjects as painful rating 8.9 +/- 0.9 SD) 40 warm, but not 2.1 1.0).(ABSTRACT TRUNCATED AT 250 WORDS)