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31.
Twenty-four adults (24 to 53 years old) with Attention-Deficit/Hyperactivity Disorder (ADHD), Combined Type, were studied in a double-blind, placebo-controlled, crossover study of Pycnogenol and methylphenidate. Pycnogenol is an antioxidant derived from the bark of the French maritime pine tree. Methylphenidate is a standard pharmaceutical intervention for ADHD. Anecdotal reports suggest that Pycnogenol improves concentration in adults with ADHD without adverse side effects. Participants received Pycnogenol, methylphenidate, and placebo, each for three weeks, in a randomized and counterbalanced order. Although ADHD symptoms improved during treatment, neither methylphenidate nor Pycnogenol outperformed the placebo control, as measured by self-report rating scales, rating scales completed by the individual's significant other, and a computerized continuous performance test. The conservative dosage levels and relatively brief length of treatment may have contributed to the absence of significant differences among treatment conditions. Implications for future research are noted. 相似文献
32.
The purpose of this study was to examine the relationships between physical activity measured as pedometer steps and performance on three motor skill tests. A secondary purpose was to determine if middle school children are meeting the recommendation for the number of daily steps. A sample (n =217) of 6th, 7th and 8th grade students participated. Each subject wore a Digi-Walker pedometer for three consecutive days. Subjects additionally recorded their pedometer steps in two 45 min.-physical education classes. There were strong significant correlations between daily steps taken by boys and girls, pedometer steps during physical education class and the AAHPERD Passing Test and the Bass Stick Balance. Similar correlations were weaker for the Side-Step Agility Test. Multivariate analysis of variance was utilized to examine variability of the three skills test by sex and year in school. Differences between students in Grades 7 and 8 on the AAHPERD Passing Test were significant. In addition, significant differences between daily pedometer steps and steps during physical education between Grades 6 and 7 were observed. Boys and girls had similar means on the AAHPERD Passing Test and Bass Stick Balance Test, but not on the Side-Step Agility Test. Scores on the three movement skills tested in this study were not strongly related to physical activity of the entire sample. Steps taken by middle school children appear not to be related to these measures of motor skills. 相似文献
33.
W T Maddox J L Dodd 《Journal of experimental psychology. Learning, memory, and cognition》2001,27(6):1367-1384
Observers completed a series of simulated medical diagnosis tasks that differed in category discriminability and base-rate/cost-benefit ratio. Point, accuracy, and decision criterion estimates were closer to optimal (a) for category d' = 2.2 than for category d' = 1.0 or 3.2, (b) when base-rates as opposed to cost-benefits were manipulated, and (c) when the cost of an incorrect response resulted in no point loss (nonnegative cost) as opposed to a point loss (negative cost). These results support the "flat-maxima" and competition between reward and accuracy (COBRA) hypotheses. A hybrid model that instantiated simultaneously both hypotheses was applied to the data. The model parameters indicated that (a) the reward-maximizing decision criterion quickly approached the optimal criterion, (b) the importance placed on accuracy maximization early in learning was larger when the cost of an incorrect response was negative as opposed to nonnegative, and (c) by the end of training the importance placed on accuracy was equal for negative and nonnegative costs. 相似文献
34.
Julian Szymański 《Cognitive Systems Research》2012,14(1):84-100
Psycholinguistic theories of semantic memory form the basis of understanding of natural language concepts. These theories are used here as an inspiration for implementing a computational model of semantic memory in the form of semantic network. Combining this network with a vector-based object-relation-feature value representation of concepts that includes also weights for confidence and support, allows for recognition of concepts by referring to their features, enabling a semantic search algorithm. This algorithm has been used for word games, in particular the 20-question game in which the program tries to guess a concept that a human player thinks about. The game facilitates lexical knowledge validation and acquisition through the interaction with humans via supervised dialog templates. The elementary linguistic competencies of the proposed model have been evaluated assessing how well it can represent the meaning of linguistic concepts. To study properties of information retrieval based on this type of semantic representation in contexts derived from on-going dialogs experiments in limited domains have been performed. Several similarity measures have been used to compare the completeness of knowledge retrieved automatically and corrected through active dialogs to a “golden standard”. Comparison of semantic search with human performance has been made in a series of 20-question games. On average results achieved by human players were better than those obtained by semantic search, but not by a wide margin. 相似文献
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Gerard M. Martin Ashar Pirzada Alexander Bridger Julian Tomlin Christina M. Thorpe Darlene M. Skinner 《Learning and motivation》2011,42(4):288-299
Rats were able to search multiple food cups in a foraging task and successfully return to a fixed, but not a variable, start location. Reducing the number of food cups to be searched resulted in an improvement in performance in the variable start condition. Performance was better when only one or two food cups had to be visited but was still impaired if the food was not found in the first cup searched. Variable start locations impaired performance when only one food cup had to be searched, if that cup was moved over the table. These findings suggest that there is an interaction between memory processes and the navigational processes that allows an animal to return to its start location after a foraging trip. It appears that a fixed location for the food or the start point of a foraging trip is a necessary precondition for accurate performance. 相似文献
38.
This research examines the relationship between behavioural inhibition (BI), family environment (overinvolved and negative
parenting, parental anxiety and parent-child attachment) and anxiety in a sample of 202 preschool children. Participants were
aged between 3 years 2 months and 4 years 5 months, 101 were male. A thorough methodology was used that incorporated data
from multiple observations of behaviour, diagnostic interviews and questionnaire measures. The results showed that children
categorised as behaviourally inhibited were significantly more likely to meet criteria for a range of anxiety diagnoses. Furthermore,
a wide range of family environment factors, including maternal anxiety, parenting and attachment were significantly associated
with BI, with inhibited children more likely to experience adverse family environment factors. No interactions between temperament
and family environment were found for child anxiety. However, a significant relationship between current maternal anxiety
and child anxiety was found consistently even after controlling for BI. Additionally, there was some evidence of a relationship
between maternal negativity and child anxiety, after controlling for BI. The results may suggest that temperament and family
environment operate as additive, rather than interactive risk factors for child anxiety. This is discussed in the context
of theoretical models of child anxiety and directions for future research. 相似文献
39.
Joachim Stoeber Matt Harvey Joshua A. Ward Julian H. Childs 《Personality and individual differences》2011,51(8):991-995
According to the Dualistic Model of Passion, two forms of passion can motivate a behavior: harmonious passion and obsessive passion. Across various life activities, studies have found that the two forms of passion show different relationships with affect, linking harmonious passion to positive affect and obsessive passion to negative affect. To investigate if this pattern also holds for online gaming, the present study investigated 160 gamers involved in playing massively multiplayer online role-playing games (MMOs) and examined positive and negative affect (a) when playing and (b) when prevented from playing. In addition, the effects of general affect and craving for playing MMOs were controlled for. Results were as expected from the Dualistic Model of Passion: harmonious passion for online gaming predicted positive affect when playing whereas obsessive passion predicted negative affect when playing and when prevented from playing. Moreover, these effects remained unchanged when general affect and craving were controlled for. With this, the present research shows that individual differences in passion for online gaming explain unique variance in gaming-related emotions. Moreover, the present findings suggests that craving is a variable that future research on positive and negative affect in online gaming should pay closer attention to. 相似文献
40.
Ford Julian D. Shevlin Mark Karatzias Thanos Charak Ruby Spinazzola Joseph 《Journal of abnormal child psychology》2022,50(9):1207-1218
Research on Child and Adolescent Psychopathology - Developmental Trauma Disorder (DTD) is a proposed child psychopathology diagnosis with emotion/somatic, attention/behavioral, and self/relational... 相似文献