Reduced right hemisphere activation in severely abused violent offenders during a working memory task: An fMRI study

This study uses functional magnetic resonance imaging (fMRI) to address two important gaps in our knowledge of brain functioning and violence: (1) What are the brain correlates of adults in the community who have suffered severe physical abuse early in life and who go on to perpetrate serious violence in adulthood? (2) What characterizes those who experience severe physical abuse but who refrain from serious violence? Four groups of participants recruited from the community (controls, severe physical child abuse only, serious violence only, and severely abused, seriously violent offenders) underwent fMRI while performing a visual/verbal working memory task. Violent offenders who had suffered severe child abuse show reduced right hemisphere functioning, particularly in the right temporal cortex. Abused individuals who refrain from serious violence showed relatively lower left, but higher right, activation of the superior temporal gyrus. Abused individuals, irrespective of violence status, showed reduced cortical activation during the working memory task, especially in the left hemisphere. Brain deficits were independent of IQ, history of head injury, task performance, cognitive strategy, and mental activity during the control task. Findings constitute the first fMRI study of brain dysfunction in violent offenders, and indicate that initial right hemisphere dysfunction, when combined with the effects of severe early physical abuse, predisposes to serious violence but that relatively good right hemisphere functioning protects against violence in physically abused children. Aggr. Behav. 27:111–129, 2001. © 2001 Wiley‐Liss, Inc.     

发展性阅读障碍视听时间整合缺陷可能的机制：视听时间再校准能力受损

发展性阅读障碍的本质一直是研究者争论的焦点。大量研究发现,阅读障碍者具有视听时间整合缺陷。然而,这些研究仅考察了阅读障碍者视听时间整合加工的整体表现,也就是平均水平的表现,却对整合加工的变化过程缺乏探讨。视听时间再校准反映了视听时间整合的动态加工过程,对内部时间表征与感觉输入之间差异的再校准困难则会导致多感觉整合受损,而阅读障碍者的再校准相关能力存在缺陷。因此,视听时间再校准能力受损可能是发展性阅读障碍视听时间整合缺陷的根本原因。未来的研究需要进一步考察发展性阅读障碍者视听时间再校准能力的具体表现,以及这些表现背后的认知神经机制。     

孤独症谱系障碍者的生物运动探测障碍：基于行为与神经的证据

关于孤独症谱系障碍个体探测生物运动的能力是否受损,已有行为研究尚存分歧。导致分歧的原因可能是实验刺激、实验任务和测量指标存在差异。然而,神经研究却一致证实其潜在的神经机制存在异常。领域特殊性观点认为该障碍可能是基于后侧颞上沟功能异常的社会性功能障碍,也可能是基于镜像神经元功能异常的社会性功能障碍;而领域一般性观点认为该障碍可能是基于背侧视觉流功能异常的视运动知觉障碍,也可能基于脑功能联结异常的弱中央统合障碍。据此,本文将从研究范式、行为表现及潜在机制三个方面梳理相关研究,以期为后续研究提供新方向。     

Political and interpersonal aspects of ethics consultation

Previous papers on ethics consultation in medicine have taken a positivistic approach and lack critical scrutiny of the psychosocial, political, and moral contexts in which consultations occur. This paper discusses some of the contextual factors that require more careful research. We need to know more about what prompts and inhibits consultation, especially what factors effectively prevent house officers and nonphysicians from requesting consultation despite perceived moral conflict in cases. The attitudes and institutional power of attending medical staff seem important, especially where innovative interventions raise ethical questions. Ethics consultants also need to address the thorny problems of the origin(s) of the consultant's authority, whistleblowing, conflicts of interest that affect the consultant, persistently poor communications in hospitals, systemic inequity in the availability or quality of services for some, and the standing of the consultant's recommendations, including their appearance in the patient's medical record.     

Sequential effects of interval duration on fixed-interval performance

The bar pressing of rats was reinforced on a multiple fixed-interval schedule. The schedule intervals were 1 and 5 min long, and the sequence was such that intervals of either duration were equally likely to be followed by intervals of the same or of the other duration. Rates were higher during 1-min and after 5-min intervals. Best fit equations for cumulative responses during the 5-min intervals produced very similar exponents regardless of preceding duration. It was concluded that preceding duration may have affected the subjects' performances through direct effects on temporal discrimination.     

Optimal temporal differentiation

In order to illuminate a light signaling a correct response, adult humans had to space their button presses according to a range of time requirements. In some conditions, the spacing needed only to exceed a minimum duration; in others, it had to fall between lower and upper bounds. Mean interresponse times always exceeded the lower limit, and decreased the more stringent were the upper bounds. Variability of interresponse times increased with larger lower bounds, but was unaffected by the size of the upper bound. Feedback about the direction of errors in conditions involving both upper and lower bounds did not affect the means, but it did reduce variability. Predictions were derived from optimality theory, based on the assumption that the critical factor was minimization of the time between correct responses. Without upper bounds, the theory overestimated the mean interresponse times by about 10%; with upper bounds, the theoretical predictions corresponded closely to the actual data. The results did not appear to reflect a scalar timing process. Optimality theory, in contrast to Weber's law, correctly predicted the variety of curves relating sensitivity to duration requirements.     

Temporal discrimination and a free-operant psychophysical procedure.

Pigeons were presented a series of keylight time periods (separated by blackouts) during which two response keys were lit, one by blue light and the other either by orange or green. Blue-key responses changed the color on the other key. Orange-key responses sometimes produced food during the first half of a time period; green-key responses sometimes produced food during the second half. In three experiments, the probability of a green-key response increased as a function of elapsed time. Experiment 1 compared performance when the duration of the keylight periods was varied across a wide range. Discrimination of performance was similar across the range of durations. Experiment 2 varied both relative reinforcement rate and the local reinforcement rate for orange-key and green-key responses. These manipulations produced changes in response bias but not discrimination sensitivity. Experiment 3 varied the local temporal placement of reinforcers within time periods and demonstrated that choice behavior was affected by differential reinforcement at different points during the time periods. The results were consistent with previous research on duration discrimination that used psychophysical trials procedures.     

Pure timing in temporal differentiation

Temporal control appears to depend on whether the critical durations are those of stimuli or those of responses. Stimulus timing (temporal discrimination) supports Weber's law, whereas response timing (temporal differentiation) indicates decreasing relative sensitivity with longer time intervals. The two types of procedure also yield different conclusions in scaling experiments designed to study the functional midpoint of two or more durations (temporal bisection procedures). In addition, the fractional-exponent power relation between emitted and required duration usually found with animals in differentiation experiments conflicts with deductions from formal analyses. The experiment reported here derived from considering differentiation arrangements as schedules of reinforcement. When analyzed from this perspective, the procedures are tandem schedules involving a required pause followed by a response, and it is the pause alone that involves temporal control. A choice procedure separated timing from responding, and enabled observations of pause timing in isolation. Pure temporal control in differentiation consisted of linear overestimation of the standard duration, and Weber's law described sensitivity. These results indicate that the two problems, the fractional-exponent power relations and the apparently different nature of sensitivity in differentiation and discrimination, disappear when temporal control is observed alone in differentiation.     

Francisco de Vitoria and Francisco Suárez on Religious Authority and Cause for Justified War: The Centrality of Religious War in the Christian Just War Tradition

Contrary to the received understanding that Francisco de Vitoria and Francisco Suárez ruled out religious war by grounding just cause in natural law, they supported a robust view of papal authority for war when necessary for the defense of the church against heretics, schismatics, and pagans as well as for the spread of Christianity and Christendom throughout the world. They believed that religious wars were in accord with natural law as a means to its fulfillment in Christianity, as a justification for the defense of the church as the one true faith, and as a moral obligation to provide all of humanity with the opportunity to receive Christian truth and grace. The neo‐Thomists' vigorous support for religious war was in the mainstream of the Christian just war tradition from the time of the wars against pagans in the early middle ages through their own time. This finding and the continuation into the modern era of sanctified patriotism stemming from the mixing of church and state especially during war that began in early Middle Ages, along with the historic roots of the recently prominent presumption against war, argue for a more complex understanding of the normative Christian just war tradition than that found among supporters of the classic interpretation of that tradition.