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791.
Motor preparation, motor execution, attention, and executive functions in attention deficit/hyperactivity disorder (ADHD). 总被引:1,自引:0,他引:1
Ester I Klimkeit Jason B Mattingley Dianne M Sheppard Paul Lee John L Bradshaw 《Child neuropsychology》2005,11(2):153-173
Attention and executive functions were investigated in medicated and unmedicated children with ADHD combined type using a novel selective reaching task. This task involved responding as rapidly as possible to a target while at times having to ignore a distractor. Results indicated that unmedicated children with ADHD showed slow and inaccurate responding. Slow responding reflected problems at the stage of movement preparation but not movement execution. An attentional impairment, rather than a motor planning problem per se, appeared to underlie the slow movement preparation. Inaccurate responding reflected problems with response inhibition and selective attention, impulsivity, set-shifting, and difficulties in maintaining vigilance. Although medicated children with ADHD did not show slow movement preparation, they did show some response inaccuracy, resulting especially from impulsive responding.These findings suggest that ADHD is characterized by slow motor preparation (but not motor execution), and deficits in selective attention, vigilance, and executive functions. Preliminary results suggest that stimulant medication may resolve some of these motor, attentional and executive function deficits. 相似文献
792.
Phenomenological qualitative methods were used to identify and describe moral elements in therapeutic relationships. Using the relational philosophy of E. Levinas (1961/1969, 1979/1987) as a base, data in which therapists and clients identified and described morally responsive experiences in therapy sessions were analyzed. These moments were often unexpected and included categories of surprise, interruption, willingness to change, and clarifications/repairs. Additional moral phenomena related to therapists' attitudes included asymmetrical indebtedness, attitude of serving, and tentativeness of diagnosis. Identified moments of moral responsiveness were frequently associated with clients' progress in therapy. This suggests that conceptually smooth and uninterrupted therapy may be less helpful than therapy that is discontinuous and able to change in the moment. 相似文献
793.
Jason Rajsic Natasha E. Ouslis Daryl E. Wilson Jay Pratt 《Attention, perception & psychophysics》2017,79(6):1643-1651
Visual working memory (VWM) plays a central role in visual cognition, and current work suggests that there is a special state in VWM for items that are the goal of visual searches. However, whether the quality of memory for target templates differs from memory for other items in VWM is currently unknown. In this study, we measured the precision and stability of memory for search templates and accessory items to determine whether search templates receive representational priority in VWM. Memory for search templates exhibited increased precision and probability of recall, whereas accessory items were remembered less often. Additionally, while memory for Templates showed benefits when instances of the Template appeared in search, this benefit was not consistently observed for Accessory items when they appeared in search. Our results show that becoming a search template can substantially affect the quality of a representation in VWM. 相似文献
794.
Gestational stress may have lasting effects on the physical and neurocognitive development of offspring. The mechanisms that may underlie these effects are of interest. Progesterone and its 5α-reduced metabolites, dihydroprogesterone and 5α-pregnan-3α-ol-20-one (3α,5α-THP), maintain pregnancy, have neurotrophic effects, and can enhance cognitive performance. We hypothesized that some of the deleterious effects of gestational stress on the cognitive performance of offspring may be related to progestogen formation. Pregnant rat dams were exposed to restraint under a bright light (thrice daily for 45 min) on gestational days 17-21 or were minimally handled controls. Dams that were exposed to restraint had lower circulating levels of 3α,5α-THP and significantly greater concentrations of corticosterone at the time of birth than did control dams. Male and female offspring, that were gestationally stressed or not, were cross-fostered to non-manipulated dams. Between postnatal days 28-30, offspring were assessed for object recognition, a prefrontal cortex (PFC)-dependent cognitive task. Restraint-exposed offspring performed more poorly in the object recognition task than did control offspring, irrespective of sex. As well, progesterone turnover to its 5α-reduced metabolites in the medial PFC (but not the diencephalon) was significantly reduced among restraint-exposed, compared to control, offspring. Progesterone turnover, and levels of 3α,5α-THP, positively correlated with performance in the object recognition task. Thus, restraint stress in late pregnancy impaired cognitive development and dysregulated progestogen formation in brain. 相似文献
795.
An important disagreement in contemporary debates about free will hinges on whether an agent must have alternative possibilities to be morally responsible. Many assume that notions of alternative possibilities are ubiquitous and reflected in everyday intuitions about moral responsibility: if one lacks alternatives, then one cannot be morally responsible. We explore this issue empirically. In two studies, we find evidence that folk judgments about moral responsibility call into question two popular principles that require some form of alternative possibilities for moral responsibility. Survey participants given scenarios involving agents that fail to satisfy these principles nonetheless found these agents to be (1) morally responsible, (2) blameworthy, (3) deserving of blame, and (4) at fault for morally bad actions and consequences. We defend our interpretation of this evidence against objections and explore some implications of these findings for the free will debate. 相似文献
796.
People are sensitive to the summary statistics of the visual world (e.g., average orientation/speed/facial expression). We
readily derive this information from complex scenes, often without explicit awareness. Given the fundamental and ubiquitous
nature of summary statistical representation, we tested whether this kind of information is subject to the attentional constraints
imposed by change blindness. We show that information regarding the summary statistics of a scene is available despite limited
conscious access. In a novel experiment, we found that while observers can suffer from change blindness (i.e., not localize
where change occurred between two views of the same scene), observers could nevertheless accurately report changes in the
summary statistics (or “gist”) about the very same scene. In the experiment, observers saw two successively presented sets
of 16 faces that varied in expression. Four of the faces in the first set changed from one emotional extreme (e.g., happy)
to another (e.g., sad) in the second set. Observers performed poorly when asked to locate any of the faces that changed (change
blindness). However, when asked about the ensemble (which set was happier, on average), observer performance remained high.
Observers were sensitive to the average expression even when they failed to localize any specific object change. That is,
even when observers could not locate the very faces driving the change in average expression between the two sets, they nonetheless
derived a precise ensemble representation. Thus, the visual system may be optimized to process summary statistics in an efficient
manner, allowing it to operate despite minimal conscious access to the information presented. 相似文献
797.
A supplemental starch feeding (SSF) procedure was used to decrease rumination in a 27‐year‐old man. A multiple baseline across mealtimes design determined treatment efficacy, followed by 26 months of maintenance and fading implemented by direct‐care staff. Following intermittent meals, four slices of bread were offered in a paced manner, after which the frequency of rumination was measured. Subsequent to the SSF sessions, the participant's rumination reduced 47%, from 0.19 per minute (8.5 per session) after baseline sessions to 0.09 per minute (4.1 per session) after treatment sessions. Ongoing measures in the natural setting continued to show reductions through maintenance and fading of the supplemental feeding. No weight gain was noted during the time the procedure was in place. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
798.
The goal of the current research was to test whether direct versus indirect measures of comparative optimism yield different results as a function of health risk severity and prevalence. A random-digit sample of community residents (N?=?259) responded to interview questions about perceived vulnerability using both direct (i.e. self-to-peer risk) and indirect comparison measures (i.e. separate questions about self and peer risk). Responses to direct comparison measures were more affected by prevalence, whereas indirect comparison measures were more affected by severity. These results may offer guidance to researchers and practitioners about when it may be more appropriate to use direct versus indirect measures of comparative health risk. 相似文献
799.
The presence of peers increases risk taking among adolescents but not adults. We posited that the presence of peers may promote adolescent risk taking by sensitizing brain regions associated with the anticipation of potential rewards. Using fMRI, we measured brain activity in adolescents, young adults, and adults as they made decisions in a simulated driving task. Participants completed one task block while alone, and one block while their performance was observed by peers in an adjacent room. During peer observation blocks, adolescents selectively demonstrated greater activation in reward-related brain regions, including the ventral striatum and orbitofrontal cortex, and activity in these regions predicted subsequent risk taking. Brain areas associated with cognitive control were less strongly recruited by adolescents than adults, but activity in the cognitive control system did not vary with social context. Results suggest that the presence of peers increases adolescent risk taking by heightening sensitivity to the potential reward value of risky decisions. 相似文献
800.