On-line syntactic processing under concurrent memory load

Thirty-six university students were tested in a plausibility judgment task using a self-paced listening paradigm under no-interference and two-digit load conditions. Listening times were longer at syntactically more complex portions of syntactically more complex sentences, and greater loads led to increased listening times. However, listening times at syntactically more complex positions in syntactically more complex sentences did not increase more than listening times at comparable positions in syntactically simple sentences under digit load conditions. The results indicate that a concurrent memory load does not reduce the availability of working memory resources used for on-line syntactic processing and, thus, provide evidence that the working memory system used for assigning syntactic structure is separate from that measured by standard working memory tasks.     

Out of sight,out of mind: Occlusion and the accessibility of information in narrative comprehension

Do readers encode the perceptual perspectives of characters during narrative comprehension? To address this question, we conducted two experiments using stories that sometimes described situations in which certain information was occluded from the protagonists’ views. We generated two related hypotheses concerning the potential impact of occlusion events on text representations. One, theevent boundary hypothesis, suggested that any salient narrative event would reduce the accessibility of prior story information. The second, theperceptual availability hypothesis, suggested that accessibility would decrease most for information no longer visible to story protagonists. In Experiment 1, the participants were slowest to respond to verification questions that asked about occluded information. In Experiment 2, we demonstrated that this effect did not extend to other, nonoccluded information. These results suggest that readers encode text information from the perceptual perspective of story protagonists. This is consistent with recent perceptual symbol views of language comprehension.     

Emotion-induced amnesia in rats: working memory-specific impairment, corticosterone-memory correlation, and fear versus arousal effects on memory

We have shown previously that psychological stress (predator exposure) impairs spatial memory in rats. We have extended that finding here to show that predator stress selectively impaired recently acquired (hippocampal-dependent) spatial working memory without affecting long-term (hippocampal-independent) spatial reference memory. We also investigated why predator exposure impairs memory. Was spatial memory impaired because of the fear-provoking aspects of predator exposure or only because the cat was a novel and arousing stimulus? If the latter possibility was correct, then any novel and arousing stimulus, independent of its emotional valence (i.e., aversive or appetitive), would impair memory. We found that spatial working memory was not impaired when the male rats were exposed to a sexually receptive female rat, a stimulus that was novel and arousing to them, but not aversive. We also found that there was an equivalent increase in serum corticosterone levels in male rats exposed to either a cat or a female rat, but only the cat-exposed rats exhibited a significant correlation between corticosterone levels and impaired memory. Overall, this series of experiments demonstrates that (1). predator stress selectively impaired working (hippocampal-dependent), but not reference (hippocampal-independent), memory; (2). a fear-provoking stimulus, and not merely novelty and increased arousal, impaired spatial memory; and (3). increased corticosterone levels correlated with impaired spatial working memory only under predator exposure, that is, fear-provoking conditions.     

Decoding digit symbol: speed,memory, and visual scanning

The authors evaluated the relative contributions of speed, memory, and visual scanning to Digit Symbol score in a sample of young adults (N = 87). Speed (Symbol Copy) explained 35% of Digit Symbol variance; only half of this was attributable to graphomotor speed (Name Printing), implying a role for perceptual speed. Visual-scanning tests (e.g., Symbol Scan) explained (on average) 34% of Digit Symbol variance, much of which was independent of perceptual-motor speed, establishing an important role for visual-scanning efficiency in Digit Symbol performance. By contrast, memory tests (on average) explained only 4% to 5% of Digit Symbol variance: statistically significant but clearly subsidiary, although a visual memory composite correlated more strongly with Digit Symbol. The Digit Symbol incidental learning procedures did, however, correlate moderately with other memory measures, suggesting that they are valid memory screening devices.     

Development of a short form for the MMPI-2 based on scale elevation congruence

The length of the Minnesota Multiphasic Personality Inventory (MMPI) is often considered a barrier to its use, leading to the development of short forms. Two methods of abbreviating the revised MMPI have now been developed. One agrees poorly with the long form in terms of which scales are elevated. The second ensures perfect congruence in which scales are elevated but requires computer administration. This article describes the development of a short form representing a compromise approach. The short form was derived using 800 psychiatric inpatients and cross-validated with samples of 658 inpatients and 266 outpatients. It is briefer than the computerized short form but does not achieve perfect congruence with the full inventory. It is longer than earlier noncomputerized short forms but demonstrates greater scale elevation congruence with the full inventory and allows estimates of more scales. The short form offers a reasonable alternative when the full inventory is impractical.     

The Tourette's Disorder Scale (TODS): development, reliability, and validity

To address the lack of a simple and standardized instrument to assess overall illness severity of Tourette's disorder (TD), the authors developed and tested a 15-item scale to measure a broad range of common symptoms including tics, inattention, hyperactivity, obsessions, compulsions, aggression, and emotional symptoms. Independent investigators used the 15-item Tourette's Disorder Scale (TODS) to assess 60 TD patients who were taking part in a double-blind placebo-controlled multicenter 8-week treatment study. Interrater reliability, internal consistency, convergent and discriminant validity, and sensitivity to change were examined. The TODS was associated with good interrater reliability, excellent internal consistency, and favorable levels of validity and sensitivity to change. Individual TODS items showed good convergent and discriminant validity against other measures. The TODS is a simple, efficient way for clinicians and parents to rate the severity of multiple symptoms commonly found in patients with Tourette's disorder.     

Holistic thinking is not the whole story: alternative or adjunct approaches for increasing the accuracy of legal evaluations

There are a number of very helpful, but often underutilized, principles and procedures that can augment decision making in clinical and legal settings. Psychologists often restrict their range of decision-making strategies and options--at the cost of maximizing diagnostic and predictive accuracy--in part as the result of "ontological-epistemological one-worldedness" (O-E O-W). However, no philosophical, logical, or scientific necessity demands strict consistency between views regarding the nature of psychological phenomena and views about how to best assess or learn about those phenomena. Relaxing this unnecessary and largely psychologically-based O-E O-W may promote greater comfort with and utilization of the methods that are discussed in this article for increasing judgmental accuracy.     

Cell phone-induced failures of visual attention during simulated driving

This research examined the effects of hands-free cell phone conversations on simulated driving. The authors found that these conversations impaired driver's reactions to vehicles braking in front of them. The authors assessed whether this impairment could be attributed to a withdrawal of attention from the visual scene, yielding a form of inattention blindness. Cell phone conversations impaired explicit recognition memory for roadside billboards. Eye-tracking data indicated that this was due to reduced attention to foveal information. This interpretation was bolstered by data showing that cell phone conversations impaired implicit perceptual memory for items presented at fixation. The data suggest that the impairment of driving performance produced by cell phone conversations is mediated, at least in part, by reduced attention to visual inputs.     

Treatment of bipolar depression

Bipolar disorder is underdiagnosed and often mistaken for unipolar depression. Bipolar patients spend 33% of their time in a state of depression compared to 11% of time spent in a manic state. Duration of time depressed and severity of depression are associated with increased risk for suicide, which occurs in 10% to 20% of bipolar patients. Antidepressants are increasingly being used as adjuncts in the depressed phase of bipolar disorder, although they provide a moderate risk for switch into mania. Lithium and some antiepileptics and atypical antipsychotics have shown antidepressant effects in the treatment of bipolar disorder. Other adjuncts for treatment-refractory patients include monoamine oxidase inhibitors and electroconvulsive therapy.     

Early maternal availability and prefrontal correlates of reward-related memory

Early emotional experiences affect developing brain systems that subsequently mediate adult learning and memory in rodents. Here we test for similar effects in squirrel monkeys (Saimiri sciureus) four years after disruptions in early maternal availability. These conditions were previously shown to generate differences in emotional behavior, hypothalamic-pituitary-adrenal stress physiology, and right ventral medial prefrontal volumes determined in adulthood by magnetic resonance imaging. This report identifies in the same monkeys variability in reward-related memory on tests with a spatial reversal. Adult monkeys that more often selected locations repeatedly rewarded before each reversal had larger right ventral medial prefrontal volumes, but not hippocampal nor dorsolateral prefrontal volumes on the left or right brain side. Differences in performance were also discerned after each spatial reversal. These findings indicate that maternal availability alters developing ventral medial prefrontal brain regions involved in reward-related memory.