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871.
Lars Nyberg Lillemor Lundin-Olsson Bj?rn Sondell Anders Backman Kenneth Holmlund Staffan Eriksson Michael Stenvall Erik Rosendahl Marcus Maxhall Gustaf Bucht 《Cyberpsychology & behavior》2006,9(4):388-395
Falls and fall-related injuries are a major problem for elderly persons. Most falls occur during walking and turning, and the risk of falling increases when attention is diverted to something besides walking. It is often difficult to standardize methods for testing balance and fall tendency in a clinically relevant setting. We describe the development of a system using a virtual environment (VE) to assess how attention demanding and unexpected events influence a person's capacity to control balance and movement. The hardware in the system consists of a head-mounted display (HMD), a magnetic tracker system, and two SGI computers. The software consists of the image generation of the VE and the management and visualization of motion tracking data. In a preliminary pilot study eight subjects (age 23-80) participated. Each subject walked on a normal floor and was visually presented a familiar outdoor environment in the HMD. They were exposed to different unexpected events, such as a virtual snowfall and tilting of the VE. Disturbances of balance and walking patterns such as changes in speed, stride length and balance reactions like slipping were observed. Two subjects experienced symptoms of cyber sickness with a SSQ score above 25 points. Walking with sensors only did not affect walking time, but in VE the subjects generally walked more slowly. Virtual tilting of the environment had an impact on balance performance during walking. This effect was not observed while the test subjects were walking in a virtual snowfall. The model needs further development but may hold a potential for clinical use. 相似文献
872.
Lo?c Lemoine Kjerstin Torre Delignières Didier 《Revue canadienne de psychologie expérimentale》2006,60(4):247-257
A number of recent papers have suggested that the series of time intervals produced in continuation tapping may have fractal properties. This proposition, nevertheless, was only based on the visual appraisal of graphical results, and was not statistically supported. In the present study, we applied the ARMA/ARFIMA modeling procedures proposed by Wagenmakers, Farrell, and Ratcliff (2005) to test for the presence of long-range dependencies in continuation tapping data. Our results demonstrate the presence of long-range dependencies in most series and offer strong support for the hypothesis that fluctuations in tapping series are fractal in nature. 相似文献
873.
Christopher M. Federico 《Political psychology》2007,28(5):535-561
Political psychologists have typically argued that ideological commitments are structured in a bipolar fashion, where a positive evaluation of conservative objects implies a negative evaluation of liberal objects (and vice versa). Individual differences in conformity to this pattern are usually attributed to an ability-related variable, i.e., political expertise . Departing from this strict focus on ability, this study examines the hypotheses that an important motivational variable—the need to evaluate , or the desire to form opinions of objects as "good" or "bad"—would (1) predict deviations from ideological bipolarity, even controlling for expertise; and (2) moderate the relationship between expertise and deviations from bipolarity. Data from two national surveys provided evidence for these hypotheses and indicated that the results extended to deviations from bipolarity in evaluations of presidential candidates and political parties. 相似文献
874.
To make technology research more effective and to deal with fierce cost competition, technology research should be more focused
on radical innovation and needs to adopt a more end-user-focused approach. Product improvement is already quite often building
on knowledge collected around consumers’ experiences with these products to come with a next, improved generation of products.
However, in case of creating novel products from “scratch,” this will be more difficult. The user-centered research approach
including insights, scenarios, and experience prototypes provides a good method to incorporate the consumer perspective in
the earliest stages of the product creation process. The development of the Ambilight TV will be used as a case to illustrate
this approach. 相似文献
875.
Remodeling of hippocampal mossy fibers is selectively induced seven days after the acquisition of a spatial but not a cued reference memory task
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Rekart JL Sandoval CJ Bermudez-Rattoni F Routtenberg A 《Learning & memory (Cold Spring Harbor, N.Y.)》2007,14(6):416-421
Relating storage of specific information to a particular neuromorphological change is difficult because behavioral performance factors are not readily disambiguated from underlying cognitive processes. This issue is addressed here by demonstrating robust reorganization of the hippocampal mossy fiber terminal field (MFTF) when adult rats learn the location of a hidden platform but not when rats learn to locate a visible platform. Because the latter task requires essentially the same behavioral performance as the former, the observed MFTF growth is seen as the consequence of specific input-dependent hippocampal activity patterns selectively generated by processing of extramaze but not intramaze cues. Successful performance on the hidden platform task requires formation of spatial memory. Increased MFTFs in hidden platform-trained rats are observed 7 d but not 2 d after training nor in swim controls. These results suggest that structural plasticity of the mossy fiber:CA3 circuit may contribute to the maintenance of long-lasting memory but not to the initial storage of the spatial context. 相似文献
876.
Some researchers argue that task switching involves task-set reconfiguration-that is, changing the existing task set to perform
a different task. Although this idea is intriguing, it is often unclear what is reconfigured and which processes are involved
in reconfiguration. We addressed these issues by defining task sets, identifying differences between them, and obtaining evidence
that was diagnostic of reconfiguration. In two experiments, subjects performed relative judgment tasks that involved comparing
a target with a reference point that repeated or switched across trials. The task was the same on every trial, but the task
set was not, because a task-set parameter-the reference point-had to be changed. Target-reference point distance effects that
changed with the reference point provided diagnostic evidence that reconfiguration occurred, and this reconfiguration led
to switch costs. We discuss how our approach can be generalized to define reconfiguration more clearly in other task-switching
situations. nt|mis|This research was supported by Grants BCS 0133202 and BCS 0446806 from the National Science Foundation
to G.D.L. 相似文献
877.
Experiences with a high emotional content (aversive) tend to be stored as long-term memories; however, there are also contextual recollections, which form a significant part of our memories. Different research has shown that the insular cortex (IC) plays an important role during aversive memory formation, yet its role during incidental/non-aversive learning like pre-exposure contextual memory formation has received little attention. The objective of this research was to establish the role of cholinergic activity in the IC through its muscarinic receptors during the formation of inhibitory avoidance (IA) memory, as well as during pre-exposure contextual memory, using a paradigm such as latent inhibition (LI). Rats with bilateral cannulae directed into the IC were trained in the LI paradigm of IA or IA task alone. The muscarinic antagonist receptor scopolamine was infused bilaterally into the IC 5 min before the pre-exposure into the dark chamber of the IA cage, one day before the conventional IA training or during the IA training day. During the IA test, the entrance latency into the dark chamber of the IA cage was measured as an index of contextual memory. The results showed that scopolamine infused before and after IA training disrupts inhibitory avoidance memory. Also, it showed that the pre-exposed saline-infused animals (LI) had a lower entrance latency compared to the group not pre-exposed (IA). However, the group that received scopolamine into the IC before, but not after, the pre-exposure to the dark chamber, presented a similar latency to the IA group, showing a blockade of the latent inhibition of the IA. These results suggest that cholinergic activity in the insular cortex is necessary during the acquisition and consolidation of avoidance memory, but appears necessary only during the acquisition of pre-exposure non-aversive contextual memory. 相似文献
878.
Jens F?rster Nira Liberman Ronald S Friedman 《Personality and social psychology review》2007,11(3):211-233
Countless studies have recently purported to demonstrate effects of goal priming; however, it is difficult to muster unambiguous support for the claims of these studies because of the lack of clear criteria for determining whether goals, as opposed to alternative varieties of mental representations, have indeed been activated. Therefore, the authors offer theoretical guidelines that may help distinguish between semantic, procedural, and goal priming. Seven principles that are hallmarks of self-regulatory processes are proposed: Goal-priming effects (a) involve value, (b) involve postattainment decrements in motivation, (c) involve gradients as a function of distance to the goal, (d) are proportional to the product of expectancy and value, (e) involve inhibition of conflicting goals, (f) involve self-control, and (g) are moderated by equifinality and multifinality. How these principles might help distinguish between automatic activation of goals and priming effects that do not involve goals is discussed. 相似文献
879.
We aimed to expand upon the demographic characteristics and gender differences among those who have met someone on the Internet who they later met offline and had sex with as well as any relationship with cybersex, sexually transmitted infections, and online sexual problems. We analyzed data collected through an online questionnaire in 2002 in Sweden including a total population of 1836 respondents of which 1458 used the Internet for sexual purposes. Of those, 35% men and 40% women reported to have met offline sex partners online. The majority reported an occurrence of one to two times, whereas 10% reported six or more times. The analysis suggested women aged 34-49 and 50-65 years, homo- and bisexual men, and singles more likely to have this experience. They were also more likely to have engaged in cybersex. No relationships were found with sexually transmitted infections or online sexual problems. The results suggest that using the Internet to find sex partners may be less hazardous for the general Internet users than pointed out by prior research about this behavior often focusing on specific sub groups of Internet users. 相似文献
880.
Participants were asked to recall the names when shown photographs of faces in both a semantic task (Experiment 1) and an episodic task (Experiments 2 and 3). When recall failed, feeling of knowing (FOK) ratings were solicited. In addition, participants reported on the strategies that they used to make their ratings, whether they could recall other pieces of information (the target-accessibility strategy, e.g., Koriat, A. (1993). How do we know that? The accessibility model of the feeling of knowing. Psychological Review, 100, 609–639) or whether the faces simply looked familiar (the cue-familiarity strategy, e.g., Schwartz, B. L., & Metcalfe, J. (1992). Cue familiarity but not target accessibility enhances feeling of knowing ratings. Journal of Experimental Psychology: Learning, Memory, and Cognition, 18, 1074–1083). In all experiments, FOK ratings were fairly accurate in that participants were successful in predicting their performance on a subsequent recognition test. More importantly, participants reported using the cue-familiarity strategy more often, although they gave higher FOK ratings when they reported using the target-accessibility strategy. The FOK ratings that were given using the two strategies were equally accurate. 相似文献