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811.
Bremner JG Johnson SP Slater A Mason U Cheshire A Spring J 《Developmental science》2007,10(5):613-624
When viewing an event in which an object moves behind an occluder on part of its trajectory, 4-month-old infants perceive the trajectory as continuous only when time or distance out of sight is short. Little is known, however, about the conditions under which young infants perceive trajectories to be discontinuous. In the present studies we focus first on infants' perception of trajectories that change during a period of occlusion. Four-month-olds perceive discontinuity in trajectories that change in height or orientation while behind an occluder, and this is true even when a change in direction could be due to an invisible bouncing collision with a surface. Further experiments reveal that infants do not perceive diagonal linear trajectories as continuous across an occlusion unless the occluding and revealing edges are orthogonal to the path of movement. Implications for theories of perceptual and cognitive development are discussed. 相似文献
812.
McMorris T Mielcarz G Harris RC Swain JP Howard A 《Neuropsychology, development, and cognition. Section B, Aging, neuropsychology and cognition》2007,14(5):517-528
The purpose of this study was to examine the effect of creatine supplementation on the cognitive performance of elderly people. Participants were divided into two groups, which were tested on random number generation, forward and backward number and spatial recall, and long-term memory tasks to establish a baseline level. Group 1 (n = 15) were given 5 g four times a day of placebo for 1 week, followed by the same dosage of creatine for the second week. Group 2 (n = 17) were given placebo both weeks. Participants were retested at the end of each week. Results showed a significant effect of creatine supplementation on all tasks except backward number recall. It was concluded that creatine supplementation aids cognition in the elderly. 相似文献
813.
814.
Many everyday activities depend on the capacity to organize and smoothly execute motor sequences. The authors tested the hypothesis that a sequencing deficit is associated with schizophrenia. They used a new method to distinguish between lower and higher order mechanisms for the impairment. The 1st task involved triggered sequences in which sensory information from 1 movement was the cue for initiation of the following movement. Results showed that the motor sequences were performed as fluently in patients as in controls. The 2nd and 3rd tasks involved sequences in which the entire movement sequence could be preplanned. Patients executed the sequences less fluently than controls but only under the condition where action sequences were required. Furthermore, the patients' fluency deficit increased with sequence complexity. The high discrimination power of Task 3 gave the authors a means to control for a potential psychometric confound involving differential discriminating power and to argue in favor of a specific higher order motor fluency deficit in patients with schizophrenia. It is suggested that basic lower order mechanisms that integrate sensory information with outgoing motor commands are preserved in schizophrenia, whereas higher order integrative mechanisms that are required for the smooth coordination of motor sequences are impaired. 相似文献
815.
Ramponi C Richardson-Klavehn A Gardiner JM 《Journal of experimental psychology. Learning, memory, and cognition》2007,33(5):843-862
The authors investigated depth-of-processing effects on conceptual priming by comparing incidental (implicit) and intentional (explicit) tests of word association. In Experiment 1, depth of processing at study influenced priming of weak and medium associates but not of strong associates. In Experiment 2, depth of processing influenced priming of weak associates but not of compound phrases (e.g., coathanger), whose preexperimental association strength matched that of weak associates. In Experiment 3, the same pattern persisted when study was auditory and test was visual, ensuring that priming was conceptual and not perceptual. In all experiments, in matched intentional tests, depth-of-processing effects occurred for all association strengths and for both phrases and associates, suggesting that the incidental tests were uncontaminated by voluntary retrieval, because they showed depth-of-processing effects only for some materials and not others, within the same participants and tests. Because depth-of-processing effects on involuntary free-association priming depend on the presence versus absence of a cohesive preexperimental representation, the memory-systems and conceptual/perceptual processing approaches to memory-test dissociations require modification to account for component processes of conceptual priming. 相似文献
816.
Silverman MM Berman AL Sanddal ND O'carroll PW Joiner TE 《Suicide & life-threatening behavior》2007,37(3):264-277
A revised and refined version of the O'Carroll et al. (1996) nomenclature for suicidology is presented, with a focus on suicide‐related ideations, communications, and behaviors. The hope is that this refinement will result in the development of operational definitions and field testing of this nomenclature in clinical and research settings. This revision would not have been possible without the international collaboration and dialogue addressing the nomenclature of suicidology since the O'Carroll et al. nomenclature appeared in 1996. Although it is doubtful that we will ever be able to construct universally unambiguous criteria to comprehensively characterize suicidal behaviors (and, overall, firmly establish the intention behind them), for scientific clarity it would be highly desirable that the set of definitions and the associated terminology be explicit and generalizable. De Leo, Burgis, Bertolote, Kerkhof, & Bille‐Brahe, 2006 , p. 5) 相似文献
817.
Mishara BL Chagnon F Daigle M Balan B Raymond S Marcoux I Bardon C Campbell JK Berman A 《Suicide & life-threatening behavior》2007,37(3):308-321
A total of 2,611 calls to 14 helplines were monitored to observe helper behaviors and caller characteristics and changes during the calls. The relationship between intervention characteristics and call outcomes are reported for 1,431 crisis calls. Empathy and respect, as well as factor-analytically derived scales of supportive approach and good contact and collaborative problem solving were significantly related to positive outcomes, but not active listening. We recommend recruitment of helpers with these characteristics, development of standardized training in those methods that are empirically shown to be effective, and the need for research relating short-term outcomes to long-term effects. 相似文献
818.
819.
Patrick W. O'Carroll Alan L. Berman Ronald W. Maris Eve K. Moscicki Bryan L. Tanney Morton M. Silverman 《Suicide & life-threatening behavior》1996,26(3):237-252
Suicidology finds itself confused and stagnated for lack of a standard nomenclature. This paper proposes a nomenclature for suicide-related behavior in the hope of improving the clarity and precision of communications, advancing suicidological research and knowledge, and improving the efficacy of clinical interventions. 相似文献
820.