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971.
We studied the development of creative cognition in children ranging from nursery school to Grade 6 (4–12 yr old, N = 511), performing a problem generation task. The task involved inventing a novel item for a classical problem solving task they had completed beforehand: the Raven Progressive Matrices (RPM). This task and the generating task both comprise matrixes of components, to which a set of transformational relations are applied; only in the first case these are inferred to solve a puzzle, but in the second they are invented to create one. We analyzed the matrixes invented in the generation task and compared them to those of the original solving task. We observed that (a) both in solving and generation, the ability to combine more than 1 relation increased with grade level, (b) within all 8 grades, except Grades 3 and 6, performance was uncorrelated between both tasks, (c) relations that were applied in the generation task often did feature in the solving task, and (d) relations occurring in both tasks were applied with different frequencies. Overall, we conclude that standard problem solving ability is not a precondition for creative reasoning and that the comprehension of relations between components featured in solving task differs from that applied in generation.  相似文献   
972.
The influence of vehicular control on motion sickness has implications for theories of motion sickness etiology. We asked whether motion sickness susceptibility might also be related to the control of non-vehicular locomotion. Participants were exposed to a console video game that featured ambulatory locomotion of a virtual avatar. In a yoked control design, individuals either played the game (players) or watched another participant's recorded game play (viewers). Viewers were more likely than players to report motion sickness. During exposure to the video game players moved more than viewers, and the movement of players was more predictable or self-similar than the movement of viewers. Coupling of movement within player-viewer pairs was greater for pairs in which the viewer later reported motion sickness than for pairs in which both participants stated that they were not motion sick. The results reveal that motion sickness incidence can be influenced by the control of stimulus motion, in general, and is not limited to control of vehicular motion. We discuss implications of these findings for theories of motion sickness etiology.  相似文献   
973.
To evaluate the efficacy of cognitive rehabilitation therapies (CRTs) for mild cognitive impairment (MCI). Our review revealed a need for evidence-based treatments for MCI and a lack of a theoretical rehabilitation model to guide the development and evaluation of these interventions. We have thus proposed a theoretical rehabilitation model of MCI that yields key intervention targets–cognitive compromise, functional compromise, neuropsychiatric symptoms, and modifiable risk and protective factors known to be associated with MCI and dementia. Our model additionally defines specific cognitive rehabilitation approaches that may directly or indirectly target key outcomes–restorative cognitive training, compensatory cognitive training, lifestyle interventions, and psychotherapeutic techniques. Fourteen randomized controlled trials met inclusion criteria and were reviewed. Studies markedly varied in terms of intervention approaches and selected outcome measures and were frequently hampered by design limitations. The bulk of the evidence suggested that CRTs can change targeted behaviors in individuals with MCI and that CRTs are associated with improvements in objective cognitive performance, but the pattern of effects on specific cognitive domains was inconsistent across studies. Other important outcomes (i.e., daily functioning, quality of life, neuropsychiatric symptom severity) were infrequently assessed across studies. Few studies evaluated long-term outcomes or the impact of CRTs on conversion rates from MCI to dementia or normal cognition. Overall, results from trials are promising but inconclusive. Additional well-designed and adequately powered trials are warranted and required before CRTs for MCI can be considered evidence-based.  相似文献   
974.
In the behavioral sciences, discussions of vision often carry an implicit assumption that the formation of inverted optic images is a result of human technology (i.e., cameras) or biological mechanisms (i.e., the chambered eye). If this assumption were true, then inverted images would be—in effect—an invention of living things, which, in turn, would have important consequences for our understanding of the evolution and psychology of vision. In this article, I briefly review the history of ideas relating vision and optics to the formation of inverted optic images. I then evaluate the necessary and sufficient conditions for the formation of inverted images. I demonstrate that inverted optic images (including inverted optic flow) can and do form in the absence of any biology and that sufficient conditions for inverted image formation predate the origins of life. Inverted images are not an invention of biological systems; rather, biological systems and human technologies exploit preexisting facts of physical optics. This conclusion is consistent with the ecological premise that life is coherent with physical law.  相似文献   
975.
The aim of the study was to investigate the influence of two different routine integration strategies on volleyball float-serve performance, and on the structure of players’ mental representations. Thirty female players participated in our study. One group trained routines using imagery, another group trained using the method of routines introduction, and the third group acted as control group. Players’ imagery ability, hand and ball velocity, serve accuracy, and players’ movement mental representation were assessed. The imagery group served significantly more accurate with significantly increased ball velocity, and players’ movement mental representation covered more clearly these of the experts.  相似文献   
976.
This study provided a systematic qualitative examination of robust sport-confidence. A focus group (2 male and 2 female participants), and follow-up interviews, with 16 (8 male and 8 female participants) elite individual sport performers, were conducted to define and contextualize the characteristics of robust sport-confidence. Data analysis procedures resulted in a definition of robust sport-confidence and the identification of 6 characteristics of robust sport-confidence. The characteristics abstracted were: multidimensional, malleable, durable, strength of belief, developed, and protective. Overall, robust sport-confidence was conceptualized as a multidimensional set of enduring positive beliefs. Future research and practical implications are discussed.  相似文献   
977.
Sounds that are equivalent in all aspects except for their temporal envelope are perceived differently. Sounds with rising temporal envelopes are perceived as louder, longer, and show a greater change in loudness throughout their duration than sounds with falling temporal envelopes. Stecker and Hafter (2000) Stecker, G. C. and Hafter, E. R. 2000. An effect of temporal asymmetry on loudness. Journal of the Acoustical Society of America, 107: 33583368.  [Google Scholar] proposed that participants ignore the decay portion of sounds with falling temporal envelopes to account for observed loudness differences, but there is no empirical evidence support this hypothesis. To test this idea, two duration-matching experiments were performed. One experiment used broadband noise and the other natural stimuli. Different groups of participants were given different instruction sets asking them to (1) simply match the duration or (2) include all aspects of the sounds. Both experiments produced the same result. The first instruction set, which represented participants' natural biases, yielded shorter subjective durations for sounds with falling temporal envelopes than for sounds with rising temporal envelopes. By contrast, asking participants to include all aspects of the sounds significantly reduced the size of the asymmetry in subjective duration, a result that supports Stecker and Hafter's hypothesis. This segregation of the stimulus at the perceptual level is consistent with observed asymmetries in loudness change and overall loudness for sounds with rising and falling temporal envelopes, but it does not account for the entire effect. The remaining portion of the effect, after considering biases due to instructions, is not likely a result of adaptation but could be associated with persistence. The amount of persistence was inferred from behavioral masking data obtained for these sounds.  相似文献   
978.
Studies on dynamic (i.e., kinesthetic) touch perception have shown that perception of many properties of wielded objects are linked to variables related to the rotational inertia of those objects. The broad nature of the sensitivity to such variables invites the question of whether various perceived functional properties of wielded objects are distinct (i.e., whether they map to rotational inertia via different functions) or whether they are perceptually equivalent (i.e., whether they map to opposite extremes of the same function). Two experiments investigated whether hammer-with-ability and poke-with-ability are perceptually equivalent (i.e., metamers) using a metameric matching strategy. The results show that metamers for hammering were not metamers for poking, and vice versa. The results suggest that haptic perception of poke-with-ability and hammer-with-ability are distinct percepts.  相似文献   
979.
We examined the influence of stance width (the distance between the feet) on postural sway and visually induced motion sickness. Stance width influences the magnitude of body sway, and changes in sway precede the subjective symptoms of motion sickness. Thus, manipulation of stance width may influence motion sickness incidence. Participants (healthy young adults) were exposed to complex, low-frequency oscillation of a moving room. Participants stood with their feet 5 cm, 17 cm, or 30 cm apart. During exposure to visual motion, the widest stance (30 cm) was associated with reduced incidence of motion sickness. For all stance widths, motion sickness was preceded by significant changes in motion of the head and torso. The results support the postural instability theory of motion sickness and suggest practical implications for the prevention of motion sickness. Adoption of wider stance may decrease the risk of motion sickness in operational situations.  相似文献   
980.
The purpose of this study was to examine the relationships of perceived motivational climate to cohesion and collective efficacy in elite female teams. A total of 124 basketball and handball athletes completed two season measures (T1, T2). Relationships were examined at an individual level both statically and across time. Canonical correlations revealed that a combination of high perceptions of an ego-involving but low perceptions of a task-involving climate were associated with low perceptions of task cohesion at Time 1. High perceptions of a task-involving but low perceptions of an ego-involving climate were associated with higher perceptions of task cohesion and collective efficacy at Time 2. Moreover, low perceptions of an ego-involving and moderately low perceptions of a task-involving climate were associated with high perceptions of social cohesion at Time 2. Regression analyses including autoregressive influence indicated that a task-involving climate positively predicted variance in T2 group integration-task and collective efficacy after controlling for T1 scores. In contrast, an ego-involving climate negatively predicted changes in T2 athletes’ perceptions of social cohesion (individual attractions to the group-social [ATG-S], group integration-social [GI-S]) and group integration-task [GI-T] after controlling for T1 scores. Theoretical and practical implications are discussed.  相似文献   
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