Gender differences in early risk factors for adolescent depression among low-income urban children

One component of a model by Nolen-Hoeksema and Girgus, who propose that risk factors for adolescent depression are more common in girls than in boys during childhood, was tested with 85 low-income, urban, African American and Latino kindergarten through fourth grade children who completed inventories of depression, stress, attributional style, gender role, and body image. Endorsing two of three predicted risk factors, girls reported slightly poorer body image and identified more strongly with a feminine gender role. Boys, however, reported a more negative attributional style. Feminine gender role was not associated with body image or negative attributional style. The applicability of the proposed model to a low-income, ethnic minority, urban population is discussed.     

Collaborative recall in face-to-face and electronic groups

When people remember shared experiences, the amount they recall as a collaborating group is less than the amount obtained by pooling their individual memories. We tested the hypothesis that reduced group productivity can be attributed, at least in part, to content filtering, where information is omitted from group products either because individuals fail to retrieve it or choose to withhold it (self-filtering), or because groups reject or fail to incorporate it (group-filtering). Three-person groups viewed a movie clip together and recalled it, first individually, then in face-to-face or electronic groups, and finally individually again. Although both kinds of groups recalled equal amounts, group-filtering occurred more often face-to-face, while self-filtering occurred more often electronically. This suggests that reduced group productivity is due not only to intrapersonal factors stemming from cognitive interference, but also to interpersonal costs of coordinating the group product. Finally, face-to-face group interaction facilitated subsequent individual recall.     

CONDITIONING MODELS OF ANXIETY

A critical examination is made of some behavioristic conceptualizations and treatments of chronic anxiety which are mostly based on a classically-conditioned fear model. A new model is proposed wherein it is assumed that tonic emotional states such as anxiety are more based on instrumental conditioning. This model has been successfully tested in experiments with monkeys. Questions remain about the relevance of this model with regard to the natural actual life etiology of these disorders.     

Central synaptic mechanisms underlie short-term olfactory habituation in Drosophila larvae

Naive Drosophila larvae show vigorous chemotaxis toward many odorants including ethyl acetate (EA). Chemotaxis toward EA is substantially reduced after a 5-min pre-exposure to the odorant and recovers with a half-time of ～20 min. An analogous behavioral decrement can be induced without odorant-receptor activation through channelrhodopsin-based, direct photoexcitation of odorant sensory neurons (OSNs). The neural mechanism of short-term habituation (STH) requires the (1) rutabaga adenylate cyclase; (2) transmitter release from predominantly GABAergic local interneurons (LNs); (3) GABA-A receptor function in projection neurons (PNs) that receive excitatory inputs from OSNs; and (4) NMDA-receptor function in PNs. These features of STH cannot be explained by simple sensory adaptation and, instead, point to plasticity of olfactory synapses in the antennal lobe as the underlying mechanism. Our observations suggest a model in which NMDAR-dependent depression of the OSN-PN synapse and/or NMDAR-dependent facilitation of inhibitory transmission from LNs to PNs contributes substantially to short-term habituation.     

Implicit measurement of positive and negative future thinking as a predictor of depressive symptoms and hopelessness

Research using explicit measures has linked decreased positive future thinking, but not increased negative future thinking, with clinical depression. However, individuals may be unable or unwilling to express thoughts about the future, and can be unaware of implicit beliefs that can influence their behavior. Implicit measures of cognition may shed light on the role of future thinking in depression. To our knowledge, the current study presents the first implicit measure of positive and negative future thinking. A sample of 71 volunteers (38 healthy; 33 with sub-clinical depression) completed both implicit and explicit measures of positive and negative future thinking. The findings indicate differences in the evaluation of both positive and negative future events between the two groups. However, group differences were more pronounced on the implicit measure. These findings point to the potential utility of an implicit measure of future thinking in mental health research and clinical practice.     

California verbal learning test indicators of Malingered Neurocognitive Dysfunction: sensitivity and specificity in traumatic brain injury

The present study used well-defined traumatic brain injury (TBI) and mixed neurological (other than TBI) and psychiatric samples to examine the specificity and sensitivity to Malingered Neurocognitive Dysfunction (MND) of four individual California Verbal Learning Test (CVLT) variables and eight composite CVLT malingering indicators. Participants were 275 traumatic brain injury and 352 general clinical patients seen for neuropsychological evaluation. The TBI patients were assigned to one of five groups using the Slick, Sherman, and Iverson (1999) criteria: no incentive, incentive only, suspect, and malingering (both Probable MND and Definite MND). Within TBI, persons with the strongest evidence for malingering (Probable and Definite) had the most extreme scores. Good sensitivity (approximately 50%) in the context of excellent specificity (> 95%) was found in the TBI samples. Issues related to the appropriate clinical application of these data are discussed.