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911.
The ability to discriminate the physical states of others could be an adaptive behavior, especially for social animals. For example, the ability to discriminate illness behavior would be helpful for avoiding spoiled foods. We report on an experiment with Japanese quails testing whether these birds can discriminate the physical states of conspecifics. The quails were trained to discriminate between moving video images of quails injected with psychoactive drugs and those in a normal (not injected) condition. Methamphetamine (stimulant) or ketamine (anesthetic) were used to produce drug-induced behaviors in conspecifics. The former induced hyperactive behavior and the latter hypoactive behavior. The subject quails could learn the discrimination and showed generalization to novel images of the drug-induced behaviors. They did not, however, show discriminative behavior according to the type and dosage of the drugs. Thus, they categorized the behavior not on the basis of degree of activity, but on the basis of abnormality. 相似文献
912.
913.
914.
E.?Paul?WileytoEmail author Janet?Audrain-Mcgovern Leonard?H.?Epstein Caryn?Lerman 《Behavior research methods》2004,36(1):41-51
The monetary choice questionnaire (MCQ) and similar computer tasks ask preference questions in order to ascertain indifference,
the perceived equivalence of immediate versus larger delayed rewards. Indifference data are then fitted with a hyperbolic
function, summarizing the decline in perceived value with delay time. We present a fitting method that estimates the hyperbolic
parameterk directly from survey responses. Binary preferences are modeled as a function of time (X2) and a transformed reward ratio (X
1), yielding logistic regression coefficients β2 and β1. The hyperbolic parameter emerges ask = β2/β1, where the logistic predictedp = .5 (the definition of indifference). The MCQ was administered to 1,073 adolescents and was scored using both standard and
logistic methods. The means for ln(k) were similar (standard, −4.53; logistic, −4.51), and the results were highly correlated (ρ = .973). Simulated MCQ data showed
thatk was unbiased, except where β1 ≥ −1, indicating a vague survey response. Jackknife standard errors provided excellent coverage. 相似文献
915.
We have developed an experimental platform that allows a large number of human participants to interact in real time within a common virtual world. Within this environment, human participants foraged for resources distributed in two spatially separated pools. In addition to varying the relative replenishment rate for the two pools (50-50, 65-35, or 80-20), we manipulated whether the participants could see each other and the entire resource distribution or had their vision restricted to resources at their own location. Two empirical deviations from an optimal distribution of the participants were found. First, the participants were more scattered within a resource pool than the resources were themselves. Second, there was systematic underutilization of the richer pool. For example, the participants distributed themselves 73% and 27% to resource pools that had replenishment rates of 80% and 20%, respectively. In addition, there were oscillations in the harvesting rate of the pools across time, revealed by a Fourier analysis with prominent power near 50 sec per cycle. The suboptimalities and oscillations were more apparent when the locations of the participants and the food were not visible. Individual participant knowledge thus affects the efficiency with which a population of participants harvests resources. 相似文献
916.
Fischer H Fransson P Wright CI Bäckman L 《Cognitive, affective & behavioral neuroscience》2004,4(3):326-334
Blood-oxygenation-level-dependent signal was measured with functional magnetic resonance imaging in 24 healthy young subjects
(12 men and 12 women) during viewing of angry, fearful, and neutral male and female face pictures. Exposure to angry male
as opposed to angry female faces activated the visual cortex and the anterior cingulate gyrus significantly more in men than
in women. A similar sex-differential brain activation pattern was present during exposure to fearful but not neutral faces.
Previous behavioral studies indicate enhanced physiological arousal in men but not in women during exposure to angry male
as opposed to female faces, and brain imaging studies have shown that the occipital cortex and the anterior cingulate gyrus
are influenced by activity in the autonomic nervous system as well as by visual attention. Hence, we suggest that the elevated
occipital and anterior cingulate activation in men during confrontation with other angry and fearful males may reflect enhanced
vigilance in a potentially dangerous situation. 相似文献
917.
Robert?G.?CookEmail author Alfred?I.?Geller Guo-Rong?Zhang Ram?Gowda 《Behavior research methods》2004,36(1):101-106
The efficiency of traditional levers and of modern touchscreen technology for training rats on a computerized visual discrimination
was studied in a series of observations. When compared with a lever-based discrimination procedure, the use of touchscreens
supported the faster development of signal tracking behavior and acquisition of a two-stimulus simultaneous visual discrimination.
It did not affect the final level of accuracy. Factors related to spatial proximity of the responses with the stimuli, sign-tracking,
and increased ease of touchscreen motor responses were suggested as possible reasons for the touchscreen training advantage.
This increased efficiency allows large numbers of animals to be tested quickly, a necessary requirement for studies involving
genetic and physiological interventions. 相似文献
918.
Quinn PC 《Psychonomic bulletin & review》2004,11(1):92-97
Quinn and Eimas (1998) reported an asymmetry in the exclusivity of the category representations that young infants form for
humans and nonhuman animals: category representations for nonhuman animal species were found to exclude humans, whereas a
category representation for humans was found to include nonhuman animal species (i.e., cats, horses). The present experiment
utilized the familiarization/novelty-preference procedure with 3- and 4-month-olds to determine the perceptual cues (i.e.,
whole stimulus, head alone, body alone) that provided the basis for this asymmetry. The data revealed the asymmetry to be
observable only with the whole animal stimuli and not when infants were provided with information from just the head or the
body of the exemplars. The results indicate that the incorporation of nonhuman animal species into a category representation
for humans is based on holistic information. 相似文献
919.
Mark W. Steege David P. Wacker Wendy K. Berg Karla K. Cigrand Linda J. Cooper 《Journal of applied behavior analysis》1989,22(1):23-33
Behavioral assessment procedures were used to prescribe and evaluate treatments of maladaptive behavior for 2 children with severe multiple handicaps. In Experiment 1, the results of an assessment of reinforcer preference were used in conjunction with a functional analysis of the conditions maintaining self-injurious behavior to prescribe a treatment for a child with severe disabilities. The treatment procedure involved the use of a pressure-sensitive microswitch to activate reinforcing stimuli during two solitary conditions, during which self-injurious behavior had occurred at high rates. The results were evaluated with a multiple baseline across settings design and indicated that self-injury decreased with concomitant increases in microswitch activation. Results were maintained at 6 weeks, 8 weeks, and 6 months. In Experiment 2, the results of behavioral assessments of reinforcer preference and self-injurious behavior were combined to develop a treatment for a second severely handicapped child, who exhibited high rates of self-injury in demand situations. This treatment was evaluated with a multiple baseline across tasks design and resulted in the elimination of self-injury for up to 15 months. 相似文献
920.
J Hy?n? P Niemi G Underwood 《Journal of experimental psychology. Human perception and performance》1989,15(1):142-152
The possibility was explored that the informativeness of a specific region within a word can influence eye movements during reading. In Experiment 1, words containing identifying information either toward the beginning or toward the end were displayed asymmetrically around the point of fixation so that the reader was initially presented with either the informative or noninformative zone. Words were read with shorter summed initial fixation time when the reading was started from the informative zone. In Experiments 2 and 3, the target words were presented in sentences that were to be comprehended. More attention was given to the informative endings of words than to redundant endings. The latter were also skipped more often. The duration of the first fixation was not affected by information distribution within the word, whereas the second fixation duration was. The results of these experiments lend good support to the hypothesis of immediate lexical control over fixation behavior and to the notion of a convenient viewing position. 相似文献