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.     

A low-cost method for digitizing videotaped continuous movements on the Macintosh

We describe an inexpensive means of digitizing videotaped positions of moving points, such as the positions of the joints of a person who is performing an action. Single-frame video images and a Macintosh computer monitor are optically superimposed, using a half-silvered mirror, and the positions of reference points in the video image are manually clicked in by the operator, so that the screen coordinates of the reference points on each frame can be stored in a text file for later analysis. The digitizing program records comments and identifying information along with the position data.     

A comparison of recollective memory and source monitoring

Participants in recognition memory experiments are often asked for additional information about their memories after each positive recognition response. Two experiments were conducted that were identical, except that the first asked participants to make remember/familiar judgments about the items they recognized, and the second asked them to make source judgments. The similarity between the recollection and source judgment data has implications for measurement issues and theory development.     

Cooperative selection of movements: The optimal selection model

How one selects a movement when faced with alternative ways of doing a task is a central problem in human motor control. Moving the fingertip a short distance can be achieved with any of an infinite number of combinations of knuckle, wrist, elbow, shoulder, and hip movements. The question therefore arises: how is a unique combination chosen? In our model, choice is achieved by consideration of the similarity between the task requirements and the optimal biomechanical performance of each limb segment. Two variants of the model account for the movements that are selected when subjects freely oscillate the fingertip and when they tap against an obstacle. An important feature of both is that the impulse of collision with an obstacle (as in drumming with the hand or tapping with the finger) is assumed to be controlled in part by aiming for a point beyond the surface being struck. Thus, a force-related control variable may be represented and controlled spatially.     

Close friendships among senior adults

The purpose of this research was to evaluate the relative contributions of personal, affective, and social exchange characteristics to satisfaction with the best friendship. Senior adults (N = 76) described and evaluated their best friendships in terms of positive and negative affect, equity, reciprocity of social support, and satisfaction. The individual's endorsement of communal and exchange orientations were included as personal characteristics. The study confirms that a communal orientation enhances satisfaction with a best friendship and that conflict and negativity detract from it. Social exchange characteristics were not related to friendship satisfaction. The need to reevaluate the role of social exchange in close relationships is discussed.     

Measurement of eye orientation of monkeys during visual discrimination

This paper describes apparatus and procedures for measuring eye orientation in the rhesus monkey without restraining the head. The main components of the apparatus are (a) a helmet on which are mounted the discriminative stimuli and the optical and other devices for obtaining a corneal reflection, (bj a special restraining chair that allows the monkey to respond to pushbuttons in front of him, yet prevents him from reaching the equipment mounted on the helmet, and (c) systems for presenting stimuli, monitoring choice responses, and recording eye orientation, which are controlled by a LINC-8 computer. The initial findings on eye orientation during performance on both a hard and an easy brightness discrimination problem are also presented.