210 research outputs found
Testing QoE in Different 3D HDTV Technologies
The three dimensional (3D) display technology has started flooding the consumer television market. There is a number of different systems available with different marketing strategies and different advertised advantages. The main goal of the experiment described in this paper is to compare the systems in terms of achievable Quality of Experience (QoE) in different situations. The display systems considered are the liquid crystal display using polarized light and passive lightweight glasses for the separation of the left- and right-eye images, a plasma display with time multiplexed images and active shutter glasses and a projection system with time multiplexed images and active shutter glasses. As no standardized test methodology has been defined for testing of stereoscopic systems, we develop our own approach to testing different aspects of QoE on different systems without reference using semantic differential scales. We present an analysis of scores with respect to different phenomena under study and define which of the tested aspects can really express a difference in the performance of the considered display technologies
Reducing Falls on the Neurovascular Unit
https://digitalcommons.psjhealth.org/stvincent-bootcamp/1015/thumbnail.jp
The role of shifting, updating, and inhibition in prospective memory performance in young and older adults.
Prospective memory performance shows a decline in late adulthood. The present article examines the role of 3 main executive function facets (i.e., shifting, updating, and inhibition) as possible developmental mechanisms associated with these age effects. One hundred seventy-five young and 110 older adults performed a battery of cognitive tests including measures of prospective memory, shifting, updating, inhibition, working memory, and speed. Age effects were confirmed in prospective memory and also obtained in shifting, updating, and inhibition. Yet, facets of executive control differently predicted prospective memory performance: While inhibition and shifting were strong predictors of prospective memory performance and also explained age differences in prospective memory, updating was not related to prospective memory performance across adulthood. Furthermore, considering executive function measures increased the amount of explained variance in prospective remembering and reduced the influence of speed. Working memory was not revealed to serve as a significant predictor of prospective memory performance in the present study. These findings clarify the role of different facets of controlled attention on age effects in prospective memory and bear important conceptual implications: Results suggest that some but not all facets of executive functioning are important developmental mechanisms of prospective memory across adulthood beyond working memory and speed. Specifically, inhibition and shifting appear to be essential aspects of cognitive control involved in age-related prospective memory performance
Explaining Age-Differences in Working Memory: The Role of Updating, Inhibition, and Shifting
Working memory (WM) represents the capacity to store and process a limited amount of information. Better understanding developmental changes of WM forms a key topic in research on neuropsychology of aging. Previous studies reveal age-differences in WM and in executive functions (EFs). Although EFs are seen as essential mechanisms in WM, the specific relation between the two cognitive constructs so far remains unclear. The present study set out to investigate the unique roles of the three main facets of EFs (i.e., updating, inhibition, and shifting) in accounting for age-related variability in WM. Therefore, one-hundred seventy-five younger and 107 older adults performed a battery of cognitive tests including measures of WM, EFs, and processing speed. A set of statistical approaches including regression analyses and path models was used to examine the cognitive correlates that could explain individual and age-related variance in WM. Significant age-differences were found on WM and on EF measures. Regression analyses and path models showed that updating and inhibition but not shifting played a major role in explaining age-related variance in WM. In sum, findings suggest that updating and inhibition are most influential for age-differences in WM. They further show that age and processing speed do not significantly contribute to variability in WM performance beyond executive resource. The present findings have implications for conceptual and developmental theories of WM and may further offer an initial empirical basis for developing possible trainings to improve older adultsā WM performance by strengthening the efficiency of updating and inhibitory processes
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MEDICATION ABORTION WITH PHARMACIST DISPENSING OF MIFEPRISTONE: A COHORT STUDY
Differential patterns of activity and functional connectivity in emotion processing neural circuitry to angry and happy faces in adolescents with and without suicide attempt
Background - Neural substrates of emotion dysregulation in adolescent suicide attempters remain unexamined. Method - We used functional magnetic resonance imaging to measure neural activity to neutral, mild or intense (i.e. 0%, 50% or 100% intensity) emotion face morphs in two separate emotion-processing runs (angry and happy) in three adolescent groups: (1) history of suicide attempt and depression (ATT, n = 14); (2) history of depression alone (NAT, n = 15); and (3) healthy controls (HC, n = 15). Post-hoc analyses were conducted on interactions from 3 group Ć 3 condition (intensities) whole-brain analyses (p < 0.05, corrected) for each emotion run. Results - To 50% intensity angry faces, ATT showed significantly greater activity than NAT in anterior cingulate gyralādorsolateral prefrontal cortical attentional control circuitry, primary sensory and temporal cortices; and significantly greater activity than HC in the primary sensory cortex, while NAT had significantly lower activity than HC in the anterior cingulate gyrus and ventromedial prefrontal cortex. To neutral faces during the angry emotion-processing run, ATT had significantly lower activity than NAT in the fusiform gyrus. ATT also showed significantly lower activity than HC to 100% intensity happy faces in the primary sensory cortex, and to neutral faces in the happy run in the anterior cingulate and left medial frontal gyri (all p < 0.006,corrected). Psychophysiological interaction analyses revealed significantly reduced anterior cingulate gyralāinsula functional connectivity to 50% intensity angry faces in ATT v. NAT or HC. Conclusions - Elevated activity in attention control circuitry, and reduced anterior cingulate gyralāinsula functional connectivity, to 50% intensity angry faces in ATT than other groups suggest that ATT may show inefficient recruitment of attentional control neural circuitry when regulating attention to mild intensity angry faces, which may represent a potential biological marker for suicide risk
Oligodendrocyte dynamics dictate cognitive performance outcomes of working memory training in mice
Previous work has shown that motor skill learning stimulates and requires generation of myelinating oligodendrocytes (OLs) from their precursor cells (OLPs) in the brains of adult mice. In the present study we ask whether OL production is also required for non-motor learning and cognition, using T-maze and radial-arm-maze tasks that tax spatial working memory. We find that maze training stimulates OLP proliferation and OL production in the medial prefrontal cortex (mPFC), anterior corpus callosum (genu), dorsal thalamus and hippocampal formation of adult male mice; myelin sheath formation is also stimulated in the genu. Genetic blockade of OL differentiation and neo-myelination in Myrf conditional-knockout mice strongly impairs training-induced improvements in maze performance. We find a strong positive correlation between the performance of individual wild type mice and the scale of OLP proliferation and OL generation during training, but not with the number or intensity of c-Fos+ neurons in their mPFC, underscoring the important role played by OL lineage cells in cognitive processing
Set-shifting as a component process of goal-directed problem-solving
In two experiments, we compared secondary task interference on Tower of London performance resulting from three different secondary tasks. The secondary tasks were designed to tap three different executive functions, namely set-shifting, memory monitoring and updating, and response inhibition. Previous work using individual differences methodology suggests that, all other things being equal, the response inhibition or memory tasks should result in the greatest interference. However, this was not found to be the case. Rather, in both experiments the set-shifting task resulted in significantly more interference on Tower of London performance than either of the other secondary tasks. Subsequent analyses suggest that the degree of interference could not be attributed to differences in secondary task difficulty. Results are interpreted in the light of related work which suggests that solving problems with non-transparent goal/subgoal structure requires flexible shifting between subgoals ā a process that is held to be impaired by concurrent performance of a set-shifting task
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