Prolonged inactivation of the hippocampus reveals temporally graded retrograde amnesia for unreinforced spatial learning in rats

We investigated whether systems consolidation of spatial memory could be detected in a non-navigational, spatial-learning test that takes advantage of rats’ natural propensity to preferentially investigate an object that was displaced relative to spatial cues more than an object that remained stationary. Previous studies using navigational spatial-learning tests have generally failed to reveal temporally-graded retrograde amnesia, possibly because the hippocampus needs to be intact for the retrieval and/or processing of navigational information during the test. In the present study, the hippocampus of rats was kept inactivated, at two sites along its septo-temporal axis (dorsal and intermediate), for four consecutive days, beginning either 3 h or 5 days after familiarization to two identical objects in an open field. Rats that had their hippocampus inactivated beginning 5 days but not 3 h after familiarization showed evidence that they remembered the previous location of the displaced object. The results suggest that systems consolidation of spatial memories can be detected using a non-navigational test of spatial memory.     

Attentional control settings modulate susceptibility to the induced Roelofs effect

When a visible frame is offset laterally from an observer's objective midline, the subjective midline is pulled toward the frame's center, causing the frame and any enclosed targets to be misperceived as being shifted somewhat in the opposite direction. This illusion, the Roelofs effect, is driven by environmental (bottom-up) visual cues, but whether it can be modulated by top-down (e.g., task-relevant) information is unknown. Here, we used an attentional manipulation (i.e., the color-contingency effect) to test whether attentional filtering can modulate the magnitude of the illusion. When observers were required to report the location of a colored target, presented within an array of differently colored distractors, there was a greater effect of the illusion when the Roelofs-inducing frame was the same color as the target. These results indicate that feature-based attentional processes can modulate the impact of contextual information on an observer's perception of space.     

Convex and Concave,Part I: Images of Emptiness in Women

The American Journal of Psychoanalysis -     

Dimensions of impulsiveness

A factor-analysis of 95 items concerned with impulsivity identified eight major components, namely, concentration, decision-making, thinking, money, excitement, temper, future orientation, and complexity.     

Islam and suicide

Suicide and homicide rates of a sample of 72 nations were associated with a cluster of social variables related to economic development but not with a cluster related to the proportion of Islamic adherents.     

The reliability and validity of the panic disorder self-report: a new diagnostic screening measure of panic disorder

This study examined the Panic Disorder Self-Report (PDSR), a new self-report diagnostic measure of panic disorder based on the 4th edition of the Diagnostic and Statistical Manual of Mental Disorders (American Psychiatric Association, 1994). PDSR diagnoses were compared with structured interview diagnoses of individuals with generalized anxiety disorder, social phobia, and panic disorder and nonanxious controls. Receiver operating characteristic analyses revealed that the PDSR showed 100% specificity and 89% sensitivity. The PDSR also demonstrated retest reliability, convergent and discriminant validity, and kappa agreement of .93 with a structured interview. Finally, the PDSR demonstrated clinical validity. Students who were identified as having panic disorder using the PDSR did not have significantly different scores on the Panic Disorder Severity Scale--Self-Report form (P. R. Houck, D. A. Speigel, M. K. Shear, & P. Rucci, 2002) than a panic disordered community sample. However, both groups had significantly higher scores than students identified as not meeting criteria for panic disorder.     

Eye movements serialize memory for objects in scenes

A gaze-contingent short-term memory paradigm was used to obtain forgetting functions for realistic objects in scenes. Experiment 1 had observers freely view nine-item scenes. After observers' gaze left a predetermined target, they could fixate from 1-7 intervening nontargets before the scene was replaced by a spatial probe at the target location. The task was then to select the target from four alternatives. A steep recency benefit was found over the 1-2 intervening object range that declined into an above-chance prerecency asymptote over the remainder of the forgetting function. In Experiment 2, we used sequential presentation and variable delays to explore the contributions of decay and extrafoveal processes to these behaviors. We conclude that memory for objects in scenes, when serialized by fixation sequence, shows recency and prerecency effects that are similar to isolated objects presented sequentially over time. We discuss these patterns in the context of the serial order memory literature and object file theory.