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161.
Early holistic models of perception presume that stimuli composed of interacting dimensions can be experienced initially as undifferentiated. This view, formalized through recourse to a Euclidean geometry of perceptual space, predicts that the orientation of axes used to create stimulus sets is unimportant to performance in speeded classification. We tested this idea by using the interacting vibrotactile dimensions of pitch and loudness. Despite perceivers’ relatively poor experience with these dimensions, we showed that the orientation corresponding to pitch and loudness was unique in vibrotactile perceptual space; subjects classified stimuli more efficiently at this orientation than at other orientations. Certain holistic models also claim that when stimulus differences are small, perceivers can recognize change without distinguishing the kind of change. We tested this idea by using a signal detection analysis of unspeededsame—different decisions. We found that subjects’ ability to notice the kind of change equaled their ability to notice the change alone. In view of these results, which indicate that pitch and loudness are primary in vibrotactile perception, we detail a new conception of dimensional interaction. 相似文献
162.
Thirsty rats were used in order to determine whether a vinegar solution, which had been paired with an injection of lithium chloride, could block the formation of an association between a pentobarbital- and a lithium chloride-induced state. During phase 1 the rats in the blocking group had a 2.0% vinegar solution paired with an injection of 240 mg/kg of lithium chloride, during phase 2 these rats were reexposed to the vinegar prior to each injection of 20 mg/kg of pentobarbital and 240 mg/kg of lithium chloride, and during phase 3 these rats were given access to a novel 0.75% saccharin solution and were injected with pentobarbital after saccharin removal. Animals with this history did not form an association between the pentobarbital- and lithium chloride-induced states during phase 2 as evidenced by their refusal to consume the saccharin solution over repeated pairings of saccharin with pentobarbital during phase 3. Control groups that received forward pairings of pentobarbital and lithium chloride, in the absence of a previously conditioned vinegar solution during phase 2, formed an association between pentobarbital and lithium chloride. These findings indicate that drug states and flavors can interfere with each others' capacity to predict the occurrence of lithium chloride. 相似文献
163.
The caudal portion of the hypoglossal nucleus (nXIIts) contains the motor neurons that control the syrinx in songbirds. In canaries, song occurs seasonally, is principally produced by males, and appears to be produced predominantly by muscles on the left side of the syrinx. The present study measures the effect of seasonal change and manipulation of testosterone levels on synapse number and morphology in nXIIts in adult female canaries. We find that synapse density is lower in testosterone-treated birds than in control birds and lower in fall than in spring. The number of vesicles per presynaptic profile increases in the spring as a result of a general increase in this measure in all synapses. The number of vesicles per presynaptic profile also increases with testosterone treatment, primarily due to an increase in the proportion of synapses associated with unusually high vesicle counts. Together, these changes suggest that large reserves of neurotransmitter may be necessary to sustain singing. Several ultrastructural differences between hemispheres are found. Postsynaptic thickenings are longer, and postsynaptic processes are larger on the left side than on the right side. In the spring, there are more vesicles per synapse on the left than on the right, but this lateralization is reversed in the fall. Thus, lateralization of song production is associated with lateral asymmetries in synapse morphology. These hemispheric differences are relatively small, like those seen at the light microscope level, encouraging further consideration of peripheral as well as CNS sources of functional lateralization. The seasonal and testosterone-induced changes in synapse number and morphology may be components of the periodic reorganization of canary vocalization. 相似文献
164.
A number of studies have demonstrated stable individual differences in the cues that generate emotions and other feeling states. These differences are assumed to arise from the cues parents use to identify their children's emotional states. As children learn about their own emotional states, they come to rely on these same cues. To test one implication of their view, the facial expressions of children (N=41) were manipulated and their feelings assessed. Some children reported emotions consistent with their expressions, while others reported emotions appropriate to the situation. In a separate procedure, their mothers were asked to identify the emotional states of children whose expressions were inconsistent with an account of their circumstances. Mothers who paid more attention to their children's expressive behavior had children who were more responsive to their own expressive behavior. In contrast, the mothers who were more responsive to situational cues had children whose emotions arose from the situational cues as well.The authors would like to thank numerous teachers and administrators of the Worcester Public School system in Worcester, Massachusetts, for their assistance. 相似文献
165.
D H Foster M Ferraro 《Journal of experimental psychology. Human perception and performance》1989,15(4):771-784
Visual processing was investigated in judgments of relative line position. Stimulus continua were generated by bisecting a straight line and displacing the segments. Experiment 1 measured discrimination of pairs of longitudinally displaced segments at equal steps along the continuum. At long (2 s) durations discrimination fell smoothly, but at short (100 ms) durations it was sharp-peaked. In Experiment 2 the short-duration stimuli were labeled with subsets of the labels no gap, just a gap, and more than just a gap. Theoretical discrimination performances were computed and the one based on no gap and just a gap closely fitted observed performance. Experiments 3 and 4 were similar to 1 and 2, with lateral replacing longitudinal displacement. Similar "categorical" performance was obtained. It was concluded that there are discrete mechanisms for early detection of relative line position and that 2 labels can be used to characterize performance in each direction. 相似文献
166.
This study examined the relations among physical fitness, body image, and locus of control. The Hall-Physical Fitness Test Profile, the Winstead and Cash Body Self-relations Questionnaire (BSRQ) and the Nowicki-Strickland Locus of Control Scale were administered to 243 freshmen. Women were significantly more positive about their physical appearance than men. Men were more positive about their physical fitness than women. Men were more physically fit than women. Men and women scoring in the internal direction viewed the physical fitness domain of their body image positively. Unlike men, internally oriented women had more positive perceptions of the health aspect of their body image. Physically fit men and women had positive attitudes toward the physical fitness component of their body image. Physically fit men differed from physically fit women in that men were more internal and held more positive attitudes toward the physical health dimension of their body images. 相似文献
167.
This study compared normal developing children, aged 34 to 51 mo., on comprehension and production of relative dimensional adjectives using object manipulations in a close elicitation procedure and on Piagetian operational tests of conservation of continuous quantity, length, reversibility and seriation. Analysis indicated a significant difference on the expressive language performance of the transitional and the concrete operational children over the preoperational children, but no significant differences occurred between the first two groups. Children who performed better on seriation were significantly better on expressive language performance. Children classified as operational for length performed better on all language measures than those classified as nonoperational. Reversibility and conservation of a continuous quantity did not differentiate children. 相似文献
168.
169.
Semantic memory in Alzheimer's disease 总被引:2,自引:0,他引:2
R D Nebes 《Psychological bulletin》1989,106(3):377-394
Patients with Alzheimer's disease have been suggested to have a semantic memory impairment not present in the normal old. This article reviews the performance of Alzheimer patients on tests of various aspects of semantic memory, including word finding, knowledge of the semantic attributes, and associates of concepts, as well as their category membership. The effect that semantic context has on cognitive processes such as lexical and semantic priming and memory encoding is also reviewed. Finally, the ability of theoretical constructs such as implicit memory and automaticity to explain intertask variability in Alzheimer patients' semantic performance is discussed. 相似文献
170.
T A Aronson 《Psychoanalytic review》1989,76(3):329-351
Many factors go into a choice of a therapeutic focus: the patient's psychopathology; the therapist's training, countertransference reactions, and ideological beliefs; and, importantly, a decision about what seems most amenable to treatment and change. As a theory, self psychology describes one aspect of the paranoid process; as such, it is an incomplete theory that complements rather than invalidates more classical theories. As a technique, however, it suggests a style and focus conducive to working with paranoid patients, one that is markedly supportive, nonconfrontational, yet also interpretive. In this context, it must be remembered how difficult it is to treat paranoid patients psychotherapeutically, much less to keep them in treatment. The strategies discussed above do not wholly replace other dynamic approaches (e.g., counterprojective techniques), nor are they universally applicable. Some patients may be more amenable than others. However, the techniques provide a very supportive framework that may help the therapist to be more available to and in contact with the paranoid patient. More broadly, this paper's application of self psychology to the theory and therapy of the paranoid disorders further illustrates the practical utility of this approach. Attention to the narcissistic developmental line, interpersonal selfobject relationships, intrapsychic conflicts and deficits, and empathic immersion in the patients's world are important adjuncts to the psychotherapy of paranoid patients. Rather than an either/or dichotomy, the principle of overdetermination suggests a both/and relationship between self psychology and traditional theory, such that the self psychological approach complements rather than contradicts the classical psychoanalytic theory. The vicissitudes of the self simply add another perspective or vantage point from which to understand and respond to the patient, one which has perhaps more applicability for preoedipally disordered patients. 相似文献