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891.
Modulation of male urogenital sniff, attack, and mount behaviors by urinary cues from female mice (SJL/J) was assessed in two experiments. Experiment 1 examined the efficacy of urine from ovariectomized and intact females in modulating the behavior of sexually experienced and inexperienced males vis-à-vis the control substance, water. It was found that urine from ovariectomized females showed no behavior-modulating properties, whereas urine from intact females decreased attack but increased sniff and mount behaviors in male mice. These findings are indicative of ovarian-dependent chemosignals contained in the urine of only intact females. Prior sexual experience had no effect on behavior of males when exposed to urine from ovariectomized females. Sniff and mount behaviors were, however, increased when sexually experienced males were exposed to urine from intact females. Using sexually inexperienced males, Experiment 2 assessed the chemosignal activity of urine from females in each of four estrous phases. It was determined that urine from proestrous and estrous females increased sniff and mount behaviors and decreased attack behavior. Urine from metaestrous females was shown to possess only sniff-inducing and mount-reducing chemosignal properties. Urine from females in diestrous lacked attack- and mount-modulating chemocues but may possess a sniff-inducing chemosignal. 相似文献
892.
Individual differences in cognitive arithmetic 总被引:2,自引:0,他引:2
Unities in the processes involved in solving arithmetic problems of varying operations have been suggested by studies that have used both factor-analytic and information-processing methods. We designed the present study to investigate the convergence of mental processes assessed by paper-and-pencil measures defining the Numerical Facility factor and component processes for cognitive arithmetic identified by using chronometric techniques. A sample of 100 undergraduate students responded to 320 arithmetic problems in a true-false reaction-time (RT) verification paradigm and were administered a battery of ability measures spanning Numerical Facility, Perceptual Speed, and Spatial Relations factors. The 320 cognitive arithmetic problems comprised 80 problems of each of four types: simple addition, complex addition, simple multiplication, and complex multiplication. The information-processing results indicated that regression models that included a structural variable consistent with memory network retrieval of arithmetic facts were the best predictors of RT to each of the four types of arithmetic problems. The results also verified the effects of other elementary processes that are involved in the mental solving of arithmetic problems, including encoding of single digits and carrying to the next column for complex problems. The relation between process components and ability measures was examined by means of structural equation modeling. The final structural model revealed a strong direct relation between a factor subsuming efficiency of retrieval of arithmetic facts and of executing the carry operation and the traditional Numerical Facility factor. Furthermore, a moderate direct relation between a factor subsuming speed of encoding digits and decision and response times and the traditional Perceptual Speed factor was also found. No relation between structural variables representing cognitive arithmetic component processes and ability measures spanning the Spatial Relations factor was found. Results of the structural modeling support the conclusion that information retrieval from a network of arithmetic facts and execution of the carry operation are elementary component processes involved uniquely in the mental solving of arithmetic problems. Furthermore, individual differences in the speed of executing these two elementary component processes appear to underlie individual differences on ability measures that traditionally span the Numerical Facility factor.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
893.
Structure and process in semantic memory: new evidence based on speed-accuracy decomposition 总被引:1,自引:0,他引:1
Reaction-time and accuracy data obtained from studies of sentence verification have not been rich enough to answer certain important theoretical questions about structures and processes in human semantic memory. However, a new technique called speed-accuracy decomposition (Meyer, Irwin, Osman, & Kounios, 1986) may help solve this problem. The technique allows intermediate products of sentence verification to be analyzed more precisely. Three experiments with speed-accuracy decomposition indicate that verification processes produce useful partial information before they are completed. Such information appears to accumulate continuously at a rate whose magnitude depends on the degree of relatedness between semantic categories. This outcome is consistent with continuous computational (e.g., semantic-feature comparison) models of semantic memory. An analysis of reaction-time minima suggests that a discrete all-or-none search process may also contribute at least occasionally to sentence verification. Further details regarding the nature of these processes and the memory structures on which they operate can be inferred from additional results obtained through speed-accuracy decomposition. 相似文献
894.
W Timberlake D J Gawley G A Lucas 《Journal of experimental psychology. Animal behavior processes》1987,13(3):302-309
An important tenet of optimal foraging theory is that foragers compare prey densities in alternative patches to determine an optimal distribution of foraging behavior over time. A critical question is over what time period (time horizon) this integration of information and behavior occurs. Recent research has indicated that rats do not compare food density in a depleting patch with that in a rich patch delayed by an hour or more (Timberlake, 1984). In the present research we attempted to specify over what time period a future rich patch would affect current foraging. The effect of future food was measured by early entry into the rich patch (anticipation) and by a decrease in food obtained in the depleting patch (suppression). The rats showed anticipation of a rich patch up to an hour distant, but suppressed current feeding only if the rich patch was 16 min distant or less. The suppression effect appeared mediated by competition for expression between anticipatory entries into the rich patch and continued foraging in the depleting patch. These results suggest that optimal foraging is based on a variety of specific mechanisms rather than a general optimizing algorithm with a single time horizon. 相似文献
895.
Some features of social living were investigated in three inbred strains of mice: C57Bl/6j, Balb/cj, and NIH. Five social behaviors--Aggression, Submission, Allogrooming, Social Rest and Rest Alone, as well as Wheel Running Activity--were recorded 2 h daily for a week, in 26 groups of seven male mice living in an enriched environment. Dominants and subordinates among strains shared some behavioral characteristics, but strain contributions upon social structure were also detected. Similarities among strains included the appearance of a single dominant mouse per group rated as the most aggressive, besides from being the animal presented with most Submissions. Allogrooming was more frequent among subordinates than among dominants and subordinates. Differences among strains were that agonistic behavior among subordinates was higher in the Balb/cj and NIH groups than in the C57Bl/6j mice. NIH mice were recorded in Rest Alone more often than mice from the other strains. C57Bl/6j dominants showed higher rates of Wheel Running Activity than subordinates. 相似文献
896.
R Ramachandran J M Pearce 《Journal of experimental psychology. Animal behavior processes》1987,13(2):182-192
In four experiments we examined the effect of an irrelevant drive on classical conditioning with food and water. In the first experiment the irrelevant drive weakened the conditioned response in extinction. In Experiments 2 and 3, this suppressive effect was found also in acquisition. Furthermore, the presence of an irrelevant drive during nonreinforced presentations of the conditioned stimulus was found to protect the conditioned response from extinction. Experiment 4 showed that the depressive effect of the irrelevant drive is manifested only when the relevant drive is present. Taken together, these results suggest that an irrelevant drive can influence conditioned responding by modulating the representation of the unconditioned stimulus. 相似文献
897.
J M Henderson A Pollatsek K Rayner 《Journal of experimental psychology. Human perception and performance》1987,13(3):449-463
The results of three different experiments suggested that the relation between an object in the fovea on fixation n and an object subsequently brought into the fovea on fixation n + 1 affects the time to identify the second object. In Experiment 1 we extended previous work by demonstrating that a previously seen related priming object speeded the time to name a target object even when a saccade intervened between the two objects. In Experiment 2 we replicated this result and further showed that the benefit on naming time was due to facilitation from the related object rather than inhibition from the unrelated object. In addition, naming of the target object was much slower in both experiments when there was not a peripheral preview of the target object on fixation n. However, because the effect of the foveal priming object was greater when the target was not present than when it was present, priming did not appear to make extraction of the extrafoveal information more efficient. In Experiment 3, fixation times were recorded while subjects looked at four objects in order to identify them. Fixation time on an object was shorter when a related object was fixated immediately before it, even though the four objects did not form a scene. The size of the facilitation was roughly comparable to that in several analogous experiments where scenes were used. The results suggest that the effects of a predictive scene context on object identification may be explainable in terms of an object-to-object or "intralevel" priming mechanism. 相似文献
898.
I Rock F Halper J DiVita D Wheeler 《Journal of experimental psychology. Human perception and performance》1987,13(3):344-352
When a figure moves behind a narrow aperture in an opaque surface, if it is perceived as a figure, its shape will often appear distorted. Under such anorthoscopic conditions, the speed or direction of the object's motion is ambiguous. However, when the observer simultaneously tracks a moving target, a figure is always perceived, and its precise shape is a function of the speed or direction of tracking. The figure is seen as moving with the speed or in the direction of the target. Thus, it is argued that eye movement serves as a cue to the figure's motion, which, in turn, determines its perceived length or orientation. 相似文献
899.
A. L. Bouhuys D. G. M. Beersma R. H. Van den Hoofdakker 《Journal of psychopathology and behavioral assessment》1987,9(1):13-33
A considerable percentage of depressed patients do not respond to antidepressive treatment. Early indicators of prognosis are needed. The aims of this study are to examine (a) whether the interpersonal behavior of patients and psychiatrist, as assessed by means of direct observation of behavior during a baseline clinical interview, might have predictive value with respect to therapeutic outcome and (b) which predictive potency measures of psychomotor activation, as assessed by less refined methods, such as global clinical judgment, might have. In the analysis used, speech-pause behavior was taken as the basic structure of the interaction. The relations of other behaviors such as looking and hand and head movement with this structure were determined. Evidence is presented that in a group of 31 depressives, improvement after a period of 10 weeks was related to observed behaviors during a baseline interview. The behaviors of the patients are interpreted as relational or nonrelational. The relational behaviors (i.e., looking yesnodding, gesturing) occur less in patients who will improve, whereas the nonrelational behaviors (i.e., intensive body touching, head movements) occur more in these patients. The nonrelational behaviors are presumed to be indicative of the state of arousal. The predictive potency of these variables could not be explained by their relationship with the baseline severity of depression, which in itself also predicted improvement. Moreover, global clinical assessment of psychomotor activation (i.e., retardation and agitation) could not be related to outcome. 相似文献
900.
The purpose of this paper is to help clients and others more fully appreciate the complex chain of events intervening between an external happening and an emotional response to that happening. It deals first with the sensory processing of physical stimulation and then presents the current state of knowledge regarding stress psychophysiology. A decision by the cortex which defines something as dangerous or threatening activates two major stress reaction pathways, the endocrine system and the autonomic nervous system, with a large number of physical consequences such as: acceleration of heart rate, increased blood pressure, reduced effectiveness of the immunological system, slowing of gastro-intestinal processes, pupil dilation, bronchial dilation and inhibition of salivation. The complexity and variety of such consequences is illustrated with a series of flow-chart diagrams, and it is suggested that these can be an additional and persuasive argument for the RET position which follows the claim of Epictetus: People are disturbed not by things, but by the views they take of them. Finally it is argued that while rapid emotional responses oftenseem to occur automatically it is because the intervening cortical processes are at times not verbalized. This is shown in the context of a diagrammatic outline of the Rational-Emotive Therapy process.Paul J. Woods, Ph.D., co-editor of this journal, is an associate fellow and an RET training supervisor of the Institute for Rational-Emotive Therapy. 相似文献