Ethanol impairs memory of a simple discrimination in adolescent rats at doses that leave adult memory unaffected

Adolescent rats are less sensitive than adults to the hypothermic, anxiolytic, motor impairing, hypnotic, and lethal effects of ethanol. In vitro experiments nevertheless suggest that hippocampal neural activity is more affected by ethanol in preweanling or adolescent rats than in adults. These data are complemented by in vivo results showing that pretraining ethanol impairs learning in adolescent rats at doses that do not affect adult learning. In order to determine if posttraining ethanol affects memory differently in adolescents than in adults, Sprague-Dawley albino rats of both ages were trained in an appetitively motivated odor discrimination in which they were required to dig in scented sand for sweetened cereal reward. Immediately after training subjects received intraperitoneal injections of 0, 0.5, or 1g/kg ethanol (12.6%). At test, 48h later, subjects were presented with unbaited discriminanda and the time (s) spent digging in the S+ and S- was measured. Adolescents, but not adults, showed impaired discrimination performance if training was followed by ethanol. A subsequent experiment discounted the possibility that impaired adolescent performance was due to ethanol-induced conditioned taste or odor aversions. It thus appears that relative to adults, memory in adolescent rats is more strongly affected by ethanol in a test of appetitive conditioning that excludes ethanol's effects on sensory and motivational influences during the learning experience.     

Fairground rides and spatial updating

A simple experiment with a rotating office chair demonstrates that the extent of counter-rotation we experience when imposed rotation has stopped is the same as the angular inaccuracy of pointing to a previously fixated object. This suggests that our conscious percept of rotation and the updating signal for the egocentric model we use to guide motor actions are closely related.     

Area-Based Socioeconomic Characteristics of Industries at High Risk for Violence in the Workplace

This study examined socioeconomic factors associated with the presence of workplaces belonging to industries reported to be at high risk for worker homicide. The proportion of 2004 North Carolina workplaces in high-risk industries was computed following spatial linkage of individual workplaces to 2000 United States Census Block Groups (n = 3,925). Thirty census-derived socioeconomic variables (selected a priori as potentially predictive of violence) were summarized using exploratory factor analysis into poverty/deprivation, human/economic capital, and transience/instability. Multinomial logistic regression models indicate associations between higher proportion of workplaces belonging to high-risk industries and Block Groups with more poverty/deprivation or transience/instability and less human/economic capital. The relationship between human/economic capital and Block Groups proportion of high-risk industry workplaces was modified by levels of transience/instability. Community characteristics therefore contribute to the potential for workplace violence, and future research should continue to understand the relationship between social context and workplace violence risk.     

The Structure of Coping in AIDS Caregivers: A Factor Analytically Derived Measure1

We report on the development of a new coping inventory. Findings demonstrate factorial invariance for 3 factors across 3 groups of caregivers. From a 19‐item summative inventory, we derived a 3‐factor model including direct problem management. positive outlook, and reality‐based coping. The model, inclusive of 9 items. appears to have consistent factor structure across groups. Results offer evidence that the 3‐factor structure is robust and may be generalized across other groups of caregivers. The model provides an acceptable fit with coping concepts of direct problem management, cognitive, and perceptual management of meaning. Findings suggest that caregivers are similar in these 3 dimensions of coping; that domain‐specific caregiving experiences are responsible for selection of coping efforts comprising these coping dimensions.     

Mental representation and learning: The influence of practice on the development of mental representation structure in complex action

ObjectivesRecent research has elicited distinct differences in mental representations between athletes of different skill levels. Such differences suggest that the structure of mental representations changes as a function of skill level. However, research examining how such mental representation structures develop over the course of learning is lacking. In the present study, we examine the effects of practice on the development of one's mental representation of a complex action during early skill acquisition.DesignFor this purpose, we created a controllable learning situation, using a repeated-measures design with a control group. More specifically, novice golfers were randomly assigned to either a practice group (n = 12) or a control group (n = 12). Both groups were tested before and after an acquisition phase of three days as well as after a three day retention interval.MethodsMental representation structures of the putt were recorded, employing the structural dimensional analysis of mental representation (SDA-M), which provides psychometric data on the structure and grouping of action concepts in long-term memory. In addition, outcome performance of the practice group was measured, using two-dimensional error scores of the putt.ResultsFindings revealed a significant improvement in task performance, as well as functional changes in the structure of the practice group's mental representation. In contrast, no functional adaptations were evident in the mental representation of the control group.ConclusionOur findings suggest that motor skill acquisition is associated with functional adaptations of action-related knowledge in long-term memory.     

The roles of vision and eye movements in the control of activities of daily living

The aim of this study was to determine the pattern of fixations during the performance of a well-learned task in a natural setting (making tea), and to classify the types of monitoring action that the eyes perform. We used a head-mounted eye-movement video camera, which provided a continuous view of the scene ahead, with a dot indicating foveal direction with an accuracy of about 1 deg. A second video camera recorded the subject's activities from across the room. The videos were linked and analysed frame by frame. Foveal direction was always close to the object being manipulated, and very few fixations were irrelevant to the task. The first object-related fixation typically led the first indication of manipulation by 0.56 s, and vision moved to the next object about 0.61 s before manipulation of the previous object was complete. Each object-related act that did not involve a waiting period lasted an average of 3.3 s and involved about 7 fixations. Roughly a third of all fixations on objects could be definitely identified with one of four monitoring functions: locating objects used later in the process, directing the hand or object in the hand to a new location, guiding the approach of one object to another (e.g. kettle and lid), and checking the state of some variable (e.g. water level). We conclude that although the actions of tea-making are 'automated' and proceed with little conscious involvement, the eyes closely monitor every step of the process. This type of unconscious attention must be a common phenomenon in everyday life.     

d-Cycloserine: effects on long-term retention of a conditioned response and on memory for contextual attributes.

d-Cycloserine (DCS), a partial agonist of the glycine recognition site of the N-methyl d-aspartate receptor, has beneficial effects on learning and memory. In order to investigate its potential to influence learning and memory of both the response and the stimulus attributes of training, male Sprague-Dawley albino rats were trained in a one-trial inhibitory avoidance task following an acute intraperitoneal injection of DCS (3 mg/kg) or an equal volume of saline. In order to measure memory for stimulus attributes, testing involved a context shift paradigm, in which subjects are tested in either the environment of training or a different one. Good memory for the contextual attributes of training is indicated by poor performance in the alternate context. Retention was assessed either 1, 7, or 14 days after training. At 1 day, Saline subjects were affected by a change in context, while DCS subjects were not. In subjects tested 1 week following training, Saline subjects were no longer affected by a change in context, in that they performed the avoidance response in both contexts. This indicates the forgetting of stimulus attributes in Saline subjects. DCS subjects did show the context shift effect at 1 week, indicating the retention of stimulus attributes. Finally, Saline subjects demonstrated the context shift rebound at 14 days, while DCS subjects performed equivalently in both contexts. Taken together, these data suggest that DCS may enhance retention of fear and slow the forgetting of stimulus attributes.     

Self-talk and affective problems in college students: valence of thinking and cognitive content specificity

The aim of this study was to develop a Self-Talk Inventory for young adults. This inventory consisted of two scales. The Negative Self-Talk Scale included three categories of self-talk (depressive, anxious, and angry thoughts) and the Positive Self-Talk Scale, three categories (minimization, positive orientation, and coping self-instructions). Participants were 982 undergraduate students (Mean age = 20.35 years, SD = 2.16). They completed the self-talk scales together with the following scales to measure symptoms of affective disorders: the Center for Epidemiological Studies Depression Scale (CES-D), the State-Trait Anxiety Inventory (STAI), and the State-Trait Anger Expression Inventory (STAXI-T). Factor analyses confirmed the hypothesized structure for the Self-Talk Inventory. The relations between self-talk and symptoms of affective disorders (depression, anxiety, and anger) were also evaluated. In general, states-of-mind -SOM- ratios and negative cognitions showed a greater association with psychological symptoms than did positive cognitions. Results concerning the cognitive characteristics of depression, anxiety, and anger were mixed and partially supported the cognitive content specificity theory.