Conditioned tolerance to morphine hypoalgesia: Compensatory hyperalgesia in the experimental group or conditioned hypoalgesia in the control group?

Five experiments used rats to examine the role of noxious stimulation in the development of contextually controlled morphine hypoalgesic tolerance and in the mediation of this tolerance by an associated hyperalgesic response. There was evidence for contextually controlled tolerance to morphine's hypoalgesic effects and an associated hyperalgesic response in rats injected with morphine and trained with noxious stimulation, but not in rats repeatedly exposed to morphine in the absence of that stimulation (Experiments 1 and 5). Latent inhibition (Experiment 2) and extinction (Experiment 3) of tolerance also depended upon pairing drug-related cues with noxious stimulation. The level of sensitivity-reactivity to noxious stimulation in morphine-tolerant rats tested with the drug was related to the intensity of the noxious stimulation that had been paired with the test context (Experiment 4). The results were interpreted to mean that some of the evidence for a Pavlovian involvement in tolerance development can be explained in terms of morphine's interference with the acquisition, but not with the expression of the hypoalgesic response otherwise acquired by cues paired with noxious stimulation.     

THE NEED FOR POWER IN WOMEN WHO WERE SEXUALLY ABUSED AS CHILDREN An Exploratory Study

Ten women who had been sexually abused as children and a matched group of women who had not been sexually abused participated in a preliminary study to explore the hypothesis that feelings of powerlessness and a compensatory need for power continue into adulthood for survivors of childhood sexual abuse. The Picture-Story Exercise (PSE) was used as an indirect assessment technique to determine the level of the need for power (McClelland, 1985; Winter, 1973, 1988). Results indicated that the stories of women with sexual abuse histories revealed a higher need for power and greater fear of power than those of nonabused women. Further content analysis of the PSE revealed that sexual abuse survivors' stories also contained more references to Finkelhor and Browne's (1986) dynamics of powerlessness, traumatic sexualization, betrayal, and stigmatization. These findings suggest important directions for future research as well as areas for therapeutic exploration.