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921.
Social foraging is suggested to increase foraging efficiency, as individuals might benefit from public information acquired
by monitoring the foraging activities of other group members. We conducted a series experiments with captive common marmosets
(Callithrix jacchus) to investigate to what extent marmosets utilize social information about food location when foraging simultaneously with
conspecifics. Subjects were confronted with dominant and subordinate demonstrators in three experiments which differed in
the amount of information about food location available to the demonstrators. In all three experiments, the focal subjects’
performance in the social condition was not enhanced in comparison to a non-social control condition. Because we could rule
out kleptoparasitism and aggressive displacements as explanations, we argue that the subjects’ tendency for scramble competition
by avoiding others and dispersing over the foraging area seems to inhibit or mask the acquisition of social information about
the location of rewarded patches. 相似文献
922.
Hofmann B 《Theoretical medicine and bioethics》2007,28(3):243-256
The science/non-science distinction has become increasingly blurred. This paper investigates whether recent cases of fraud in science can shed light on the distinction. First, it investigates whether there is an absolute distinction between science and non-science with respect to fraud, and in particular with regards to manipulation and fabrication of data. Finding that it is very hard to make such a distinction leads to the second step: scrutinizing whether there is a normative distinction between science and non-science. This is done by investigating one of the recent internationally famous frauds in science, the Sudbø case. This case demonstrates that moral norms are not only needed to regulate science because of its special characteristics, such as its potential for harm, but moral norms give science its special characteristics. Hence, moral norms are crucial in differentiating science from non-science. Although this does not mean that ethics can save the life of science, it can play a significant role in its resuscitation. 相似文献
923.
Breidegard B 《Behavior research methods》2007,39(4):824-834
This article presents the first technology ever for online registration and interactive and automatic analysis of finger movements during tactile reading (Braille and tactile pictures). Interactive software has been developed for registration (with two cameras and a microphone), MPEG-2 video compression and storage on disk or DVD as well as an interactive analysis program to aid human analysis. An automatic finger-tracking system has been implemented which also semiautomatically tracks the reading aloud speech on the syllable level. This set of tools opens the way for large scale studies of blind people reading Braille or tactile images. It has been tested in a pilot project involving congenitally blind subjects reading texts and pictures. 相似文献
924.
von Leupoldt A Rohde J Beregova A Thordsen-Sörensen I zur Nieden J Dahme B 《Behavior research methods》2007,39(3):606-609
Standardized sets of films have been shown to be effective for eliciting emotional states in adults, but no comparable validated stimuli are available for children. We therefore examined the effects of three pre-selected film clips each of 3-min duration in eliciting a pleasant, neutral and unpleasant emotional state in 297 children aged between 6 and 12 years. After the films were presented on a video projector, affective ratings were obtained with the Self-Assessment-Manikin on the emotional dimensions of valence and arousal. Increasing pleasure ratings were observed from the unpleasant to the neutral to the pleasant film. Associated arousal ratings were stronger for the unpleasant and pleasant films compared to the neutral film. Overall, results showed successful elicitation of targeted emotional states only marginally influenced by age, gender or prior experience with the films. The use of these films is therefore suggested for future studies on emotions in children. 相似文献
925.
Desai AV Wilsmore B Bartlett DJ Unger G Constable B Joffe D Grunstein RR 《Behavior research methods》2007,39(3):673-681
Several driving simulators have been developed which range in complexity from PC based driving tasks to advanced "real world" simulators. The AusEd driving simulator is a PC based task, which was designed to be conducive to and test for driver fatigue. This paper describes the AusEd driving simulator in detail, including the technical requirements, hardware, screen and file outputs, and analysis software. Some aspects of the test are standardized, while others can be modified to suit the experimental situation. The AusEd driving simulator is sensitive to performance decrement from driver fatigue in the laboratory setting, potentially making it useful as a laboratory or office based test for driver fatigue risk management. However, more research is still needed to correlate laboratory based simulator performance with real world driving performance and outcomes. 相似文献
926.
927.
Theoretical models of attention for affective information have assigned a special status to the cognitive processing of emotional facial expressions. One specific claim in this regard is that emotional faces automatically attract visual attention. In three experiments, the authors investigated attentional cueing by angry, happy, and neutral facial expressions that were presented under conditions of limited awareness. In these experiments, facial expressions were presented in a masked (14 ms or 34 ms, masked by a neutral face) and unmasked fashion (34 ms or 100 ms). Compared with trials containing neutral cues, delayed responding was found on trials with emotional cues in the unmasked, 100-ms condition, suggesting stronger allocation of cognitive resources to emotional faces. However, in both masked and unmasked conditions, the hypothesized cueing of visual attention to the location of emotional facial expression was not found. In contrary, attentional cueing by emotional faces was less strong compared with neutral faces in the unmasked, 100-ms condition. These data suggest that briefly presented emotional faces influence cognitive processing but do not automatically capture visual attention. 相似文献
928.
Does trauma exposure have a long-term impact on the brain and behavior of healthy individuals? The authors used functional magnetic resonance imaging to assess the impact of proximity to the disaster of September 11, 2001, on amygdala function in 22 healthy adults. More than three years after the terrorist attacks, bilateral amygdala activity in response to viewing fearful faces compared to calm ones was higher in people who were within 1.5 miles of the World Trade Center on 9/11, relative to those who were living more than 200 miles away (all were living in the New York metropolitan area at time of scan). This activity mediated the relationship between group status and current symptoms of posttraumatic stress disorder. In turn, the effect of group status on both amygdala activation (fearful vs. calm faces) and current symptoms was statistically explained by time since worst trauma in lifetime and intensity of worst trauma, as indicated by reported symptoms at time of the trauma. These data are consistent with a model of heightened amygdala reactivity following high-intensity trauma exposure, with relatively slow recovery. 相似文献
929.
Coloring only a single letter in the Stroop task can result in a reduction or elimination of Stroop interference. The present experiments were designed to test whether this modulation of Stroop interference occurs at all letter positions. Specifically, we investigated whether Stroop interference was reduced when the colored letter occupied the optimal viewing position (OVP). The experiments show that Stroop interference is not reduced at the OVP (Experiment 1) and that Stroop interference at the OVP is significantly greater than at other letter positions (Experiments 1 and 2). This finding has important theoretical and methodological consequences for studies of automatic processing in visual word recognition. 相似文献
930.
Koster EH Crombez G Verschuere B Vanvolsem P De Houwer J 《Experimental psychology》2007,54(2):161-171
Models of attention and emotion have assigned a special status to the processing of threatening information: Facilitated attentional capture by threat and its prioritized processing would allow for swift and adequate action to potentially dangerous stimuli. In four experiments, we examined the time-course of facilitated orienting of attention to threatening scenes in the exogenous cueing paradigm. Threat value and presentation duration of the cues were systematically varied. Facilitated attentional capture by threat was limited to highly threatening pictures presented for 100 ms. No attentional effects were observed with a 28 ms cue presentation duration. At slightly longer cue presentations, 200 ms and 500 ms, results indicated no and even reduced attentional capture by threat compared with neutral information. The present results provide support for the idea that threat facilitates fast attentional orienting to its location, followed by the inhibition of attention to threat. 相似文献