Gender effect on the right-left discrimination task in a sample of heroin-dependent patients

Rationale: Discriminating right from left is an everyday cognitive ability. Repeated exposure to certain drugs, such as heroin, can produce poor performance on many cognitive tasks. However, it is yet unclear whether drug abuse impairs the ability of right-left discrimination. Objectives: The aim of the present study is to examine whether the spatial ability measured by the right-left discrimination task can be affected by heroin abuse and whether such drug effect, if it exists, is gender related. Methods: A paper-and-pen test was used. The test consists of line drawings of a person with no arm, one arm, or both arms crossing the vertical body axis of the figure. The line drawings are viewed from the back, from the front, or randomly alternating between the back and front drawings. The subjects task is to mark which is the right or left hand in the figure as fast as possible. Results: A main finding in this study was that the ability to discriminate between left and right in visual space was impaired in heroin-dependent patients. Especially, heroin-dependent females performed poorer than control females in all conditions but heroin-dependent males only performed poorly in part of conditions. Conclusions: Recent heroin abuse impairs the ability of right-left discrimination and such impairment is gender related: heroin-dependent females demonstrated greater performance deficits than males.

EEG activities in the orbitofrontal cortex and dorsolateral prefrontal cortex during the development of morphine dependence, tolerance and withdrawal in rhesus monkeys

Investigating the activities of the prefrontal cortex (PFC) in the process of addiction is valuable for understanding the neural mechanism underlying the impairments of the PFC after drug abuse. However, limited data are obtained from primate animals and few studies analyze Electroencephalogram (EEG) in the gamma band, which plays an important role in cognitive functions. In addition, it is yet unclear whether drug abuse affects the orbitofrontal cortex (OFC) and dorsolateral PFC (DLPFC) - the two most important subregions of the PFC - in similar ways or not. The aim of this study is to address these issues. We recorded EEG in the OFC and DLPFC in three rhesus monkeys. All animals received a course of saline (NaCl 0.9%, 2 ml) injection (5 days) followed by 10 days of morphine injection (every 12 h), and then a further series of saline injection (7 days). A main finding in the present study was that morphine decreased EEG power in all frequency bands in a short period after injection in both the OFC and DLPFC in monkeys. And gamma power decreased not just in short period after morphine injection but lasted to 12 h after injection. Moreover, we found that although the changes in EEG activities in the OFC and DLPFC at 30-35 min after injection were similar, the DLPFC was more sensitive to the effect of morphine than the OFC. (c) 2005 Elsevier B.V. All rights reserved.

异文化圈社会规范层次结构模型的比较研究

The relationship between the management and the culture was explored from the view of social norm's theory. In concrete terms, the differences of the hierarchical structure of the social norm among the Chinese, the Japanese and the American were studied systematically by using interview, case study, questionnaire survey and the structure equation model, etc. The results were: (1) The basic two types of the social norms of the Chinese, the American and the Japanese were the same: the external control norm and the internal control norm. The basic dimensions of the two types of norms composed of moral principle, value orientation, the law and the rules, and the social custom were consistent among the three countries. Furthermore, the dimensions of social norms were hierarchical because of the functioning of the different culture, which consisted of the hierarchical structure system. (2) Although there were the same dimensions among the three countries, the contents of these dimensions had both the common norms surpassing the specific culture and the particular norms depending on the specific culture. (3) The basic structures of the social norms in China and in Japan were the same: the internal control norms played a main role and the external control norm was auxiliary. On one hand, within the internal norm of the Chinese, the moral principle was the main force while the value orientation was the supplementary; within the external norm, the law and the rules was the main force while the social culture custom was supplementary. On the other hand, the relationship between the external and the internal dimensions of the Japanese turned out to be contrary to those of the Chinese. (4) The structure of the American social norms were different from the Chinese: for the American, the external control norm played a main role while the internal control norm was assistant. Furthermore, the law and the rule was the major aspect while the social costumes was the second in the external control dimension. In addition, the value orientation led the performance style of the American, while the moral principle played the second role in the internal control structure. (5) The social norms related to the management performance were found including work responsibility, organization commitment, meeting making-decision, communication style, work duty and interpersonal conflict by inventory and case study. The mangers from China, Japan and America had significant different views on paying attention to the management norms. In a word, the culture differences of the social norm were the fundamental reason of the management conflict.