Gender differences in emotional and overt/covert aggressive responses to stress

We examined the role of stress exposure on gender differences in hostile (emotional and behavioral) reactions within the context of a laboratory paradigm. Aggressive behavior was indexed via the intensity (overt) and the duration (covert) of putative shocks delivered to a confederate. Half of the participants were exposed to a chronic stressor (high stress) and half were not (low stress). Participants' emotional responses were measured via self-report mood ratings before and after the experiment. Men displayed higher aggression in both stress conditions, which corresponded to their ratings of state hostility. On the other hand, women in high stress delivered lower intensity shocks, and this decreased overt aggression was positively correlated with sadness ratings. However, women did not decrease their levels of shock duration (covert aggression) under high stress and showed equivalent shock duration compared with men in high stress. These findings are discussed in terms of differential overt manifestations of distress between men and women.     

The effects of phencyclidine and chlordiazepoxide on target biting of confined male mice

Target-biting of confined mice increases following delivery of tail shock and decreases during a tone that precedes the shock. Both phencyclidine and chlordiazepoxide reduced biting (dose dependently) following shock and had no effect on biting during the tone. These observations are discussed in reference to previous reports, which infer that the effects of phencyclidine and chlordiazepoxide on aggression might depend upon the baseline rate of the behavior.     

Facing Ourselves

At the time of this writing, a widely publicized, waived-consent trial is underway. Sponsored by Northfield Laboratories, Inc. (Evanston, IL) the trial is intended to evaluate the emergency use of PolyHeme^®, an oxygen-carrying resuscitative fluid that might prevent deaths from uncontrolled bleeding. The protocol allows patients in hemorrhagic shock to be randomized between PolyHeme^® and saline in the field and, still without consent, randomized between PolyHeme^® and blood after arrival at an emergency department. The Federal regulations that govern the waiver of consent restrict its applicability to circumstances where proven, satisfactory treatments are unavailable. Blood—the standard treatment for hemorrhagic shock—is not available in ambulances but is available in hospitals. The authors argue that the in-hospital stage of the study fails to meet ethical and regulatory standards.     

文化能力与文化友好型医患关系

医院文化休克是糟糕的患者体验,严重影响医患关系。医院文化休克与医生父爱主义、尊重患者自主和医患契约三种医患关系模式观将人片面化的共同缺陷相关。解决医院文化休克问题,应回到作为完整人的文化人,将患者作为文化人,提高文化差异敏感性,增强文化能力。这就要求加强教育和培训,建立文化谦逊态度;注重非临床的患者体验;增强语言和沟通能力,改善服务态度;改善医疗环境和流程,加大医疗资源的供给;建立文化友好型研究者−受试者关系,建立文化友好型医患关系。

     

重症感染非抗感染措施的思考

近年来严重感染与感染性休克治疗策略的主要进展是对强化血糖控制、糖皮质激素等疗法的再评价。同时,也出现了诸如血管加压素、他汀类药物、选择性口腔/肠道脱污染等新的治疗措施,并取得了一定成果。本文对相关研究进展进行综述,以阐明集束化策略和管理水平的提高可能是最终降低重症感染病死率的关键。     

男女两性在文化震荡、心理健康及其关系中的差异比较

采用自编问卷对1555名30岁及以上被试受文化震荡的影响程度及其心理健康进行调查,分别探讨不同生活环境和环境相同但受教育程度不同的男女两性在两变量及其关系中的差异。结果表明:(1)总体上,男性报告的文化事件的主观影响明显比女性更积极,但其心理健康水平却明显低于女性;男女两性在文化震荡与心理健康之间均存在显著正相关,但具有不同特点。(2)不同生活环境和同一生活环境中不同受教育程度的男女两性在文化震荡、心理健康中均存在不同程度的差异;在这两变量间也均存在不同方面的显著正相关。     

Line-orientation generalization following signalled-reinforcer training

Three naive and three nonnaive pigeons key pecked for food on a multiple variable-interval 1-minute variable-interval 1-minute schedule with a black zero-degree vertical line on a white surround associated with one component and a black line shifted 30 degrees to the right (+30 degree) associated with the other component. Subsequently, a signalled-reinforcer procedure was introduced in the +30 degree component, i.e., whenever the reinforcer was available for the next response, the key changed to blank white. Following this training, the original unsignalled-reinforcer condition was re-instated. Line orientation generalization tests were given at the end of signalled-reinforcer training and after the second unsignalled-reinforcer condition. The signalled-reinforcer procedure reduced response rate in the +30-degree component in all subjects but facilitated responding during the zero-degree component (behavioral contrast) for two of the naive subjects only. However, average generalization gradients following signalled-reinforcer training indicated peak shift in two subjects and area shift in all five subjects that completed the experiment. There was no apparent relation between contrast and peak shift or degree of area shift. The data were interpreted as supporting the notion that the signalled-reinforcer procedure segments a variable-interval schedule into extinction and fixed ratio 1 segments.     

Schedules of food postponement: II. Maintenance of behavior by food postponement and effects of the schedule parameter

In Experiment I, food-deprived, feeder-trained squirrel monkeys pressed a lever to postpone brief electric shocks (Response-Shock=Shock-Shock interval=30 seconds). Forty-one three-hour sessions of shock postponement were followed by 120 sessions of concurrent shock and food postponement. The shock schedule was unchanged and the food schedule was Response-food interval–20 seconds, Food-food interval 10 seconds. After concurrent shock and food postponement, the shock schedule was discontinued and 40 sessions of food postponement ensued, followed by 53 sessions of extinction. After extinction, food postponement was resumed for 11 sessions. Stable responding with low food rates was maintained under food-postponement after the concurrent schedule. Responding decreased to low levels under extinction and recovered immediately to previous levels when the food-postponement schedule was re-instated. In Experiment II, a parameter of the food-postponement schedule was studied sequentially. Using the same subjects, the Response-food–Food-food interval was manipulated from four seconds to 80 seconds with several orders of presentation. Relations of response rates and food rates to the parameter were similar to those seen under shock postponement. Exposure to very short postponement times (four seconds), resulting in very high food rates, decreased but did not abolish subsequent responding at longer postponement times. Results are discussed from the point of view that reinforcing functions of stimuli consequent on responding depend on a prior history of scheduled contact with those stimuli.     

Negative reinforcement with shock-frequency increase

Two avoidance-conditioning experiments in which responding delayed shocks are reported. Rats receiving an average of two shocks per minute (imposed condition) could produce, by pressing a bar, a 3-min alternate condition. Six (Experiment I) or more (Experiment II) shocks occurred in the alternate condition. All shocks in the alternate condition were delayed and delivered at 1-sec intervals. With long delays, all subjects produced the alternate condition and spent a large percentage of each session in the alternate condition. The first experiment demonstrated that the longer the delay from onset of the alternate condition to onset of the shocks, the more session time spent in the alternate condition. The second experiment indicated that despite increased shock frequency, behavior is acquired and maintained when responding leads to sufficient delay. Individual subjects produced the alternate condition by bar pressing in essentially one of two patterns. One pattern, termed postshock, involved bar pressing immediately after shock; the other, termed posttransition, involved responding immediately after the transition from the alternate to the imposed condition. These results indicate that shock-frequency reduction is not necessary for avoidance conditioning; delay to shock onset is sufficient.