Amodal completion in visual search: preemption or context effects?

In a previous study, search for a notched-disk target abutting a square among complete-disk nontargets and squares was inefficient in 250-ms exposures, but relatively efficient in 100-ms exposures. This finding was interpreted as evidence that amodal completion proceeds through a mosaic and then a completion stage, with the latter preempting the former. We used the same target but changed its context: Nontargets were instead notched disks near squares. Task set was also different: Participants searched for a complete disk. Contrary to the prediction of the preemption model, search was efficient in the 100-ms condition and inefficient in the 250-ms condition. We propose that in both the present and the previous studies, the target was ambiguous, and task set and context affected how it was perceived. In both experiments, set effects were evident for 100-ms exposures; context effects were evident for 250-ms exposures.     

Preserved fronto-striatal plasticity and enhanced procedural learning in a transgenic mouse model of Alzheimer's disease overexpressing mutant hAPPswe

Mutations in the amyloid precursor protein (APP) gene inducing abnormal processing and deposition of beta-amyloid protein in the brain have been implicated in the pathogenesis of Alzheimer's disease (AD). Although Tg2576 mice with the Swedish mutation (hAPPswe) exhibit age-related Abeta-plaque formation in brain regions like the hippocampus, the amygdala, and the cortex, these mice show a rather specific deficit in hippocampal-dependent learning and memory tasks. In view of recent findings showing that neural systems subserving different forms of learning are not simply independent but that depressing or enhancing one system affects learning in another system, we decided to investigate fronto-striatal synaptic plasticity and related procedural learning in these mutants. Fronto-striatal long-term depression (LTD) induced by tetanic stimulation of the cortico-striatal input was similar in Tg2576 and wild-type control mice. Behavioral data, however, pointed to an enhancement of procedural learning in the mutants that showed robust motor-based learning in the cross maze and higher active avoidance scores. Thus, in this mouse model of AD, an intact striatal function associated with an impaired hippocampal function seems to provide neural conditions favorable to procedural learning. Our results suggest that focusing on preserved or enhanced forms of learning in AD patients might be of interest to describe the functional reorganization of the brain when one memory system is selectively compromised by neurological disease.     

Predicting performance times from deliberate practice hours for triathletes and swimmers: what, when, and where is practice important?

In Studies 1 and 2, the authors evaluated deliberate practice theory through analyses of the relationship between practice and performance for 2 populations of athletes: triathletes and swimmers, respectively. In Study 3, the authors obtained evaluations of practice from athletes' diaries. Across athletes, length of time involved in fitness activities was not related to performance. For the triathletes, a significant percentage of variance in performance was captured by practice. This was not so for sprint events for the swimmers, in which gender was a significant predictor. In the diaries, physical activities were perceived as enjoyable. In contrast to the results obtained from questionnaires, enjoyment did not covary with an activity's relevance to improving performance. Although these findings highlight the importance of sport-specific practice, the authors question a domain-independent account of expertise based on deliberate practice.     

Visual but not spatial working memory deficit in children with spina bifida

Twenty children with spina bifida and twenty controls were assessed on a battery of visuospatial working memory tests. Children with spina bifida performed as well as the control group in the visuospatial test and in the forward and backward versions of the Corsi test, but were impaired in the 'House Visual Span.' This test, designed in our lab, provides specific information regarding visual ability to discriminate between pictorial targets and lures, and requires specific visual processing of stimuli. These results are discussed in terms of working memory models and are viewed as supporting the distinction between the visual and spatial components of working memory.     

Influence of training on maintenance of equilibrium on a tilting platform

To assess the influence of training on the maintenance of equilibrium on a tilting platform, 13 young healthy male athletes aged 19 to 33 years were randomly divided into experimental (n=7) and control (n=6) groups. Two experimental sessions were performed before and after a specific 4-wk. training by the experimental group. Subjects stood upright on a tilting platform. The athletes were asked to maintain the platform as horizontal as possible during a 30-sec. test. The three-dimensional movements of the platform versus the ground were recorded by using a computerized optoelectronic digitiser. The platform plane was calculated and its directrix computed. The area of oscillation and instantaneous angular velocity of the directrix at standardized height were calculated. In both groups the area of oscillation and the angular velocity were reduced in Session 2, but the reduction was significant only in the experimental group. Specific training can significantly improve skill at maintaining equilibrium in young healthy sport performers.     

Measuring surface achromatic color: Toward a common measure for increments and decrements

Surface color is traditionally measured by matching methods. However, in some conditions, the color of certain surfaces cannot be measured: The surface simply looks brighter or darker than all the patches on a matching scale. We studied the reliability, validity, and range of application of three different types of simulated Munsell scales (white-, black-, and split-surrounded) as methods for measuring surface colors in simple disk-ring displays. All the scales were equally reliable for matching both increments and decrements, but about 20% of the increments were unmatchable on the white-surrounded scale, about 13% of the decrements were unmatchable on the black-surrounded scale, and about 9% of the increments were unmatchable on the split-surrounded scale. However, matches on all the scales were linearly related. Therefore, it is possible to convert them to common units, using regression parameters. These units provide an extended metric for measuring all increments and decrements in the stimulus space, effectively removing ceiling and floor effects, and providing measures even for surfaces that were perceived as out of range on some of the scales.     

Storage of verbal associations is sufficient to activate the left medial temporal lobe

Neuroimaging studies have shown that memory encoding activates the medial temporal lobe (MTL). Many believe that these activations are related to novelty but it remains unproven which is critical - novelty detection or the rich associative encoding it triggers. We examined MTL activation during verbal associative encoding using functional magnetic resonance imaging. First, associative encoding activated left posterior MTL more than single word encoding even though novelty detection was matched, indicating not only that associative encoding activates the MTL particularly strongly, but also that activation does not require novelty detection. Moreover, it remains to be convincingly shown that novelty detection alone does produce such activation. Second, repetitive associative encoding produced less MTL activation than initial associative encoding, indicating that priming of associative information reduces MTL activation. Third, re-encoding familiar associations in a well-established way had a minimal effect on both memory and MTL activation, indicating that MTL activation reflects storage of associations, not merely their initial representation.     

Gender and locus of control correlates of body image dissatisfaction

The study concerned sex and various locus of control correlates of body image satisfaction. The results indicated that men and women differ significantly in the degree and in the direction of dissatisfaction towards their bodies, which were consistent with the culturally defined ideals for men and women. Significant differences were also observed regarding self-perceptions, suggesting that women more than men are more likely to suffer from depression and have lower self-esteem which was itself associated with body image satisfaction. Individual beliefs about perceived control towards achieving an ‘ideal’ body shape were assessed using a new locus of control scale which correlated significantly with two scales measuring attitudes relating to body shape. The results from this new scale suggest that perceived locus of control beliefs are important predictors of the resulting behaviours and self-perceptions associated with body shape satisfaction and dissatisfaction.     

Very long-term retention of a novel

This study investigated the very long-term retention of a full-length novel originally studied as part of a university undergraduate course. One hundred and forty former students completed three tests designed to assess retention of Charles Dickens' Hard Times. Retention intervals ranged from 3 to 39 months. Subjects' responses when they were asked to report their most vivid and enduring memory of the novel were consistent with story grammar models which claim that components of a story which are higher in a hierarchy are remembered better than those lower in the hierarchy. A free recall test of the names and roles of the characters in the novel found that retention of both declined rapidly in the first few months following acquisition, that names were forgotten more quickly than roles, and that retention of both had stabilized above baseline before the longest retention interval. These data are interpreted in terms of a schema account of memory retention, in which retention of schematic knowledge (roles), but not non-schematic knowledge (names) can be mediated by abstract knowledge structures. The results of a fact verification test showed that memory for events of high importance in the novel was better than memory for events of low importance, consistent with models that suggest that texts and stories are represented hierarchically in memory. Confidence ratings also declined over time and showed that subjects generally assessed the accuracy of their responses correctly. The significant predictors of memory for the novel were retention interval and the mark obtained on a coursework essay on Hard Times.     

What are the relationship experiences of in which one member identifies as transgender? A systematic review and meta-ethnography

Transgender individuals and their partners may face unique challenges that other couples do not. These unique challenges merit investigation, understanding and consideration by systemic practitioners in order to provide a culturally attuned service for transgender clients. A systematic review of the literature into the experiences of couples in which one member is transgender identified 22 qualitative papers. A translation and synthesis of constructs from these papers utilising a meta-ethnographic approach generated a number of third order constructs organised into nine overarching themes. These themes included experiences of stigma and discrimination, issues of power, privilege, visibility and identity, and experiences of dissonance and dysphoria that required adjustments and negotiations on the personal and relationship levels. Implications for practice and avenues for future research are discussed.