Clock drawing performance and brain morphology in mild cognitive impairment and Alzheimer's disease

The Clock Drawing Test (CDT) is a widely used instrument in the neuropsychological assessment of Alzheimer's disease (AD). As CDT performance necessitates several cognitive functions (e.g., visuospatial and constructional abilities, executive functioning), an interaction of multiple brain regions is likely. Fifty-one subjects with mild cognitive impairment, 23 with AD and 15 healthy controls underwent high-resolution magnetic resonance imaging. Optimized voxel-based morphometry (VBM) was performed to investigate the putative association between CDT performance and gray matter (GM) density throughout the entire brain. In the first step of analysis (p<.001, uncorrected), VBM revealed a reduced GM density in numerous cortical (temporal lobe, frontal lobe, parietal lobe, cerebellum) and subcortical (thalamus, basal ganglia) brain regions to be associated with poorer CDT performance. When corrected for multiple comparisons (p<.01), the associations remained significant predominantly in the left temporal and--less pronounced--the right temporal lobe. VBM demonstrated CDT performance to depend on the integrity of widely distributed cortical and subcortical areas in both brain hemispheres with accentuation in the left-sided temporal lobe region.     

Rapid figure-ground responses to stereograms reveal an advantage for a convex foreground

Convexity has long been recognised as a factor that affects figure - ground segmentation, even when pitted against other factors such as symmetry [Kanizsa and Gerbino, 1976 Art and Artefacts Ed.M Henle (New York: Springer) pp 25-32]. It is accepted in the literature that the difference between concave and convex contours is important for the visual system, and that there is a prior expectation favouring convexities as figure. We used bipartite stimuli and a simple task in which observers had to report whether the foreground was on the left or the right. We report objective evidence that supports the idea that convexity affects figure-ground assignment, even though our stimuli were not pictorial in that depth order was specified unambiguously by binocular disparity.     

On the origins of emergent differential sample behavior

Two experiments evaluated the source(s) of emergent differential sample behavior in pigeons. Initially, pigeons learned two-sample, two-alternative symbolic matching in which different patterns of sample responding were required to produce the comparisons. Afterwards, two other samples nominally identical to the comparisons were added to the matching task. On new-sample trials, completion of either sample-response requirement produced comparison alternatives which were either the same as or different from the alternatives on the familiar-sample trials. Differential responding to the new samples developed only when the comparisons were the same as the familiar samples. The results are consistent with acquired sample equivalence and adventitious reinforcement accounts of emergent sample behavior and are inconsistent with bidirectional transfer (symmetry) between the response patterns explicitly required to the originally trained (familiar) samples and the subsequently reinforced comparisons.     

ASTEF: A simple tool for examining fixations

In human factors and ergonomics research, the analysis of eye movements has gained popularity as a method for obtaining information concerning the operator's cognitive strategies and for drawing inferences about the cognitive state of an individual. For example, recent studies have shown that the distribution of eye fixations is sensitive to variations in mental workload---dispersed when workload is high, and clustered when workload is low. Spatial statistics algorithms can be used to obtain information about the type of distribution and can be applied over fixations recorded during small epochs of time to assess online changes in the level of mental load experienced by the individuals. In order to ease the computation of the statistical index and to encourage research on the spatial properties of visual scanning, A Simple Tool for Examining Fixations has been developed. The software application implements functions for fixation visualization, management, and analysis, and includes a tool for fixation identification from raw gaze point data. Updated information can be obtained online at www.astef.info, where the installation package is freely downloadable.     

Short-Term Inpatient DBT Combined with Metacognitive Interventions for Personality Disorders: A Pilot Acceptability and Effectiveness Study

This study aims at evaluating the effectiveness of an intensive 1-month residential treatment course in an Italian psychiatric unit for patients meeting criteria for personality disorders (PD). This study involved 189 patients consecutively admitted to the unit and assessed at admission and discharge. The inpatient program was based on Dialectical Behavior Therapy (DBT) combined with Metacognitive interventions. Primary outcome was a reduction of general symptom severity (as measured by SCL-90-R). Secondary outcomes were reduction in depression (BDI), interpersonal problems (IIP-47). Other outcomes were impulsivity (BIS-11), aggressiveness (AQ), and dissociation (DES). We found a significant reduction in symptom severity, as well as in depression, interpersonal problems, dissociation, impulsivity and aggressiveness. The size of this benefit was predicted mostly by number of criteria met at SCID-II and intake scores mostly for impulsiveness and dissociation. In conclusion, intensive 1-month residential DBT combined with metacognitive interventions can be effective in treating patients with any PD presenting with severe global suffering, prominent self-harm and suicidal risk.

     

Nonconsensual neurocorrectives,bypassing, and free action

Philosophical Studies - As neuroscience progresses, we will not only gain a better understanding of how our brains work, but also a better understanding of how to modify them, and as a result, our...     

Gender effects among undergraduates relating to suicide risk, impulsivity, aggression and self-efficacy

The present study investigated the association of impulsivity, aggression and self-efficacy with protective factors against suicide. The study population consisted of 300 Italian university students (141 males, 159 females); mean age 24.2 (SD = 3.01). Participants were assessed by means of the Reasons for Living Inventory, the Aggression Questionnaire, the Barratt Impulsiveness Scale, and the General Self-Efficacy Scale. Correlations between reasons for living and aggression and impulsivity scores were weak. However, for those individuals with high self-efficacy, aggression and impulsivity were associated with stronger reasons for living. These results support the possibility that increasing general self-efficacy could be a useful target for interventions directed toward suicide prevention in individuals with problems in emotional control.     

Desire to change one’s multimodality and its relationship to the use of different transport means

Using data collected from French employees of a transportation institute and residents of the US San Francisco Bay Area, we operationalize a segmentation of mobility patterns based on objective, subjective, and desired amounts of mobility by various modes and overall. We especially focus on the degree of multimodality in an individual’s current modal mix and desired changes to that mix through the use of a “multimodality index”. The clusters that result showed some similarities and some differences across countries, where the latter are likely due to disparities in the sampling strategies and in the land use/transportation/cultural milieux. In both cases, however, the clusters have useful policy implications, enabling us, for example, to distinguish car users who might be inclined to reduce car use and increase transit use from those who are largely content with their current modal baskets.