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871.
Five obliquely rotated factor analyses were performed on items from Eysenck and Eysenck’s (1975) EPQ, Zuckerman’s (1975) Sensation-Seeking Scale, and Strelau’s (1972) temperament inventory (STI), administered to 277 subjects (Ss). The analyses were used to examine the relationships between the personality dimensions E, N, L, P and Sensation-Seeking, which pertain mainly to social situations, attitudes and feelings, and questionnaire-derived measures of nervous system properties, which, while validated on experimental indices of nervous system properties derived from Nebylitsyn’s (1972) model, are expressed as characteristic features of social behavior, work style and activity. Four factors were identified—extraversion/strength of excitation/mobility; self-control of affect/stability/caution; strength of inhibition/verbal control/motor expressiveness/ nonmanipulativeness; and sensation-seeking/nervousness. The results offer support for Eysenck’s claim of some identity between excitatory strength and E, for the reported relationship between E and mobility, and for Eysenck’s conditioning postulate. They also suggest that similar temperamental variables underlie individual differences in both social and occupational/motor activity. Since Strelau’s STI items are validated on experimental indices of nervous system properties, it follows that typological characteristics may be inferred from questionnaire data derived from both behavioral categories.  相似文献   
872.
Special difficulties are encountered when attempting to provide intracranial cannulation of small animals that have floating or fragile skull bones. The technique described was developed for mice but seems applicable to other species. The cannula system is inexpensive and easy to use. A wound clip anchor seems superior to either skull screws or bonded acrylic, producing less damage to the brain and no necrosis of bone or tissue on the wound margin. Patency data up to 25 days is presented, and the system is as efficacious as other techniques.  相似文献   
873.
The theoretical role of proprioception in the perception and control of human movement is elusive because of the obvious inability to manipulate experimentally the various receptive systems. Individuals who have had the metacarpophalangeal joint and joint capsule removed and replaced with silastic inserts afford a unique opportunity to evaluate a principal source of proprioception, namely, slowly adapting joint afferents. In a set of experiments, we show that such individuals show no deficits in finger localization following joint replacement. We take this and other complementary findings as a preliminary basis for proposing a dynamic rather than kinematic account of movement production. In addition, we provide a reconceptualization of the function of proprioceptive information in the CNS. Our arguments focus on proprioceptive inputs as tuning or modulating interneuronal pools rather than providing dimension-pecific information to the brain, as is commonly assumed.  相似文献   
874.
Patterns varying in form goodness and size were presented for 15, 30, and 45 msec. The experiment included three independent groups of subjects. Half of the first group were presented size variations with good figures, while the other half were shown size variations with poor figures. Half of the second group were presented goodness variations with small figures, while the other half were shown goodness variations with large figures. A third group experienced variations in both goodness and size. The major findings were: (1) poor figures and large figures were judged “longer” than good or small figures when varied within a session; (2) this effect vanished when the different levels of size or goodness were presented to separate groups of subjects; (3) the magnitude of the difference in temporal estimation was the same for size and goodness when each was varied in isolation; (4) when size and form goodness were varied orthogonally in the same session, both dimensions produced reliable changes in temporal estimation. These data are discussed in light of current theoretical explanations of the filled duration illusion.  相似文献   
875.
Recent experiments have indicated that contrast effects can be obtained with vowels by anchoring a test series with one of the endpoint vowels. These contextual effects cannot be attributed to feature detector fatigue or to the induction of an overt response bias. In the present studies, anchored ABX discrimination functions and signal detection analyses of identification data (before and after anchoring) for an [i]-[I] vowel series were used to demonstrate that [i] and [I] anchoring produce contrast effects by affecting different perceptual mechanisms. The effects of [i] anchoring were to increase within-[i] category sensitivity, while [I] anchoring shifted criterion placements. When vowels were placed in CVC syllables to reduce available auditory memory, there was a significant decrease in the size of the [I]-anchor contrast effects. The magnitude of the [i]-anchor effect was unaffected by the reduction in vowel information available in auditory memory. These results suggest that [i] and [I] anchors affect mechanisms at different levels of processing. The [i] anchoring results may reflect normalization processes in speech perception that operate at an early level of perceptual processing, while the [I] anchoring results represent changes in response criterion mediated by auditory memory for vowel information.  相似文献   
876.
The present experiment examined a model and a supplementary explanation of feedback acceptance. The model consisted of inventory responding under a yea-saying response set and the explanation stated that feedback is accepted because it is accurate and persuasive. "Neurotic" and stable undergraduates (n = 120) took several personality inventories and then rated the accuracies of personality "interpretations." As predicted, the model mirrored every detail of feedback acceptance; also, the accuracy of interpretations related most simply to their acceptance and the undergraduates changed their self-perceptions in the direction of the interpretations. Contrary to predictions, individual differences in persuasibility did influence feedback acceptance.  相似文献   
877.
A semantic differential study of development of antonym meanings revealed methodological problems (e.g., concept-scale interaction and developmental changes in scale-checking style) not fully considered in previous semantic differential investigations of child language development. Twenty adjectives were rated on 10 scales by subjects from grades K to 5 (approximately 6 through 11 years old) and adults. Analyses by means, polarity ratings, and average sums of squared differences failed to yield consistent developmental trends. Subjects' choices of scale ratings did show clear age-related differences: Grades K and 1 chose extreme ratings almost exclusively; grades 2 through 4 showed an increase in neutral choices and decreases in extreme ratings; grades 4 and 5 and adults chose extreme ratings least often, neutral choices most often, and more intermediate ratings than any younger subjects. Results show that scale choice is a crucial factor in designing semantic differential studies with children, there is a low correlation between mean scores and ratings given by individual children, and shifts in scale-checking style should be considered when interpreting apparent developmental changes in children's semantic differential ratings.  相似文献   
878.
Experiments 1 and 2 examined the effects of various durations of lickcontingent delays of reinforcement on the development of schedule-induced polydipsia. Food was provided every 1 min in the absence of licking. Delays of 1 min or more effectively disrupted the development of the licking behavior. In Experiments 3 and 4 a lick-contingent stimulus was provided in addition to the delay of food delivery. A light, which was turned on by a lick and turned off by food, greatly enhanced the development of polydipsia under delays that had previously prevented such development. A tone proved less effective than the light in promoting the development of polydipsia. Adventitious reinforcement and conditioned punishment explanations of these results were considered. A distinction was drawn between the mechanism responsible for the development of schedule-induced behavior and that responsible for its maintenance.  相似文献   
879.
Choice and reinforcement delay   总被引:9,自引:8,他引:1       下载免费PDF全文
Previous studies of choice between two delayed reinforcers have indicated that the relative immediacy of the reinforcer is a major determinant of the relative frequency of responding. Parallel studies of choice between two interresponse times have found exceptions to this generality. The present study looked at the choice by pigeons between two delays, one of which was always four times longer than the other, but whose absolute durations were varied across conditions. The results indicated that choice is not uniquely determined by the relative immediacy of reinforcement, but that absolute delays are also involved. Models for concurrent chained schedules appear to be more applicable to the present data than the matching relation; however, these too failed to predict choice for long delays.  相似文献   
880.
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