Role of CA3 and CA1 subregions of the dorsal hippocampus on temporal processing of objects

Previous research in the dorsal CA1 and dorsal CA3 subregions of the hippocampus has been shown to play an important role in mediating temporal order memory for spatial location information. What is not known is whether the dorsal CA3 and dorsal CA1 subregions of the hippocampus are also involved in temporal order for visual object information. Rats with dorsal CA1, dorsal CA3 or control lesions were tested in a temporal order task for visual objects using an exploratory paradigm. The results indicated that the controls and the dorsal CA3 lesioned rats preferred the first rather then the last object they had explored previously, indicating good memory for temporal order of object presentation. In contrast, rats with dorsal CA1 lesions displayed a profound deficit in remembering the order of the visual object presentations in that they preferred the last object rather than the first. All three groups of rats preferred a novel object compared to a previously explored object suggesting normal detection of visual object novelty. The results suggest that only the dorsal CA1, but not dorsal CA3, region is critical for processing temporal information for visual objects without affecting the detection of new visual objects.     

Bilateral entorhinal cortex lesions impair acquisition of delayed spatial alternation in rats

Entorhinal cortex lesions induce significant reorganization of several homotypic and heterotypic inputs to the hippocampus. This investigation determined whether surviving heterotypic inputs after bilateral entorhinal lesions would support the acquisition of a learned alternation task. Rats with entorhinal lesions or sham operations were trained to acquire a spatial alternation task. Although the sham-operated rats acquired the task within about 3 weeks postsurgery, rats with bilateral entorhinal lesions failed to learn the task after 12 consecutive weeks of training despite heterotypic sprouting of the cholinergic septodentate pathway and the expansion of the commissural/associational fiber plexus within the dentate gyrus. Thus, heterotypic sprouting failed to ameliorate significantly the effects of bilateral entorhinal lesions. Rather, entorhinal lesions produced a persistent impairment of spatial memory, characterized by a mixture of random error production and perseverative responding.     

Comprehensive treatment of three patients with comorbid OCPD and ADHD

Three patients were seen in an outpatient setting with work difficulties involving disorganization and task completion. They were evaluated and found to have significant symptoms of both attention-deficit/hyperactivity disorder, inattentive subtype and obsessive-compulsive personality disorder and were then treated with a creative combined behavioral and medication treatment, which emphasized the use of external aides (eg, paraprofessionals). Significant symptom reduction was observed as a result of this combined intervention.     

Training cognitive skills in virtual reality: measuring performance.

Across a variety of operational environments, virtual reality (VR) is being increasingly used as a means of simulating hazardous work conditions in order to allow trainees to practice advanced cognitive skills such as problem-solving and decision-making. Replicating dangerous conditions particularly involving heavy machinery in the real world can be dangerous and costly. The use of VR is therefore appealing across many industries such as aviation, mining, and rail. However, while the number of training prototypes increase less focus is being given to appropriate evaluation of the training provided via this technology. Increasing skills acquisition and performance does not depend solely on the appropriate design of simulation training. Of equal importance are strong performance measures which can ultimately feedback on the success or otherwise of training and highlight any deficits to guide ongoing improvements. To ensure cognitive skills acquired in a virtual training environment (VTE) are transferable to the real world, training objectives need to be tied directly to realistic scenario events which in turn are directly linked to measures of specific required behaviors.     

Regulatory Focus Strategies Scale: A measure of individual differences in the endorsement of regulatory strategies

Regulatory focus theory proposes that people can have a promotion or a prevention focus when pursuing goals and choosing strategies. The Regulatory Focus Strategies Scale (RFSS), a scale that assesses the endorsement of promotion and prevention strategies for goal pursuit, is developed and validated in three studies. Exploratory and confirmatory factor analyses in Australia and Japan showed that promotion- and prevention-focused strategic endorsement formed two largely uncorrelated factors. The RFSS exhibits adequate reliability, and discriminant and convergent validity. A cross-cultural comparison showed that Australians were more promotion- but less prevention-focused than Japanese students. The RFSS provides an additional measure that is useful in future research on self-regulatory strategies.     

Propranolol and the prevention of post-traumatic stress disorder: is it wrong to erase the "sting" of bad memories?

The National Institute of Mental Health (Bethesda, MD) reports that approximately 5.2 million Americans experience post-traumatic stress disorder (PTSD) each year. PTSD can be severely debilitating and diminish quality of life for patients and those who care for them. Studies have indicated that propranolol, a beta-blocker, reduces consolidation of emotional memory. When administered immediately after a psychic trauma, it is efficacious as a prophylactic for PTSD. Use of such memory-altering drugs raises important ethical concerns, including some futuristic dystopias put forth by the President's Council on Bioethics. We think that adequate informed consent should facilitate ethical research using propranolol and, if it proves efficacious, routine treatment. Clinical evidence from studies should certainly continue to evaluate realistic concerns about possible ill effects of diminishing memory. If memory-attenuating drugs prove effective, we believe that the most immediate social concern is the over-medicalization of bad memories, and its subsequent exploitation by the pharmaceutical industry.     

False memory in a short-term memory task

The Deese/Roediger-McDermott (DRM; Roediger & McDermott, 1995) paradigm reliably elicits false memories for critical nonpresented words in recognition tasks. The present studies used a Sternberg (1966) task with DRM lists to determine whether false memories occur in short-term memory tasks and to assess the contribution of latency data in the measurement of false memories. Subjects studied three, five, or seven items from DRM lists and responded to a single probe (studied or nonstudied). In both experiments, critical lures were falsely recognized more often than nonpresented weak associates. Latency data indicated that correct rejections of critical lures were slower than correct rejections of weakly related items at all set sizes. False alarms to critical lures were slower than hits to list items. Latency data can distinguish veridical and false memories in a short-term memory task. Results are discussed in terms of activation-monitoring models of false memory.