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Ratings of pre-morbid intelligence level, derived from the hospital charts of 26 chronic schizophrenics, were correlated with the post-mortem brain volume measures of cortex, white matter, central grey matter, and ventricles. Contrary to hypothesis, no significant correlations were found. 相似文献
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Fighting pairs of isolated DBA/2 mice showed a significant increase in tail-flick response latencies independent of whether opponents were losing or winning the combat. The effect lasted less than 10 min in both animals. Elevated pain thresholds were also found in isolates that attacked a nonaggressive conspecific, and were prevented by naltrexone (0.2 mg/kg), while a larger dose (1.0 mg/kg) inhibited the attack behavior. A small increase in pain threshold was observed after exposure of isolates to the test box alone, while isolation per se had no effect on baseline tail-flick latencies. The data demonstrate that endogenous pain suppressing systems are activated during attack and suggest that this opioid-mediated antinociception is a correlate of the isolation syndrome, reflecting enhanced arousal of the attacking animal. 相似文献
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Iwata BA 《The Behavior analyst / MABA》1988,11(2):149-157
Default technologies evolve from failure. Within the realm of human behavior, technologies based on the use of aversive contingencies can be conceptualized as default technologies because they come into play when natural contingencies or positive reinforcement fail to produce a desired behavioral outcome. Historical as well as contemporary events suggest that it is a mistake for behavior analysts to advocate for the adoption of aversive technologies. We must, however, continue to play a leading role in the development of such technologies so that they will be used in an appropriate manner. Furthermore, the eventual elimination of aversive technologies will be possible only through continued, careful, and experimental analysis of the contexts of failure in which they are born. 相似文献