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111.
Depression in some patients with spinal cord injuries may be clinically significant and, when present, should be treated to
decrease morbidity including decreased physical functioning. Depression associated with spinal cord injury (SCI) may be misevaluated,
due to (1) nonspecific multifactorial production of depression symptoms and (2) SCI-specific decrease in somatic sensory central
nervous system input. The Somatic Suppression Hypothesis suggests that SCI patients have difficulty experiencing any intense
emotion because of suppression of physiological arousal. In addition, cognitive processes that may reduce depression in SCI
patients include: (1) attribution of somatic symptoms of depression to medical (biological) causes, (2) realistic, positive
expectations for physical improvement, and (3) the perception that the disability of the SCI is only minimally related to
the patient’s self-care after complete evaluation. Health personnel should accept lack of depression in SCI, and should encourage
positive realistic expectations of recovery. 相似文献
112.
Increases in self-attention as a function of decreases in the relative size of one’s subgroup in a heterogeneous group context
have been shown to result in increased regulation of behavior toward social (normative) standards for behavior. The present
study demonstrated increased regulation of behavior toward a personal standard for behavior as a function of variations in
group composition. One hundred twenty-five subjects individually completed the Creativity subscale of Scott’s Personal Value
Scale assessing attitudes toward originality. They then completed a word-association task in groups ranging in size from 2
to 8. Originality of word-associations was determined by reference to previously established word-association norms and norms
based on frequency of responses given in the present study. Results indicate that originality in responses increase as the
relative size of one’s own subgroup decreases (indexing increases in self-attention) for subjects who value originality. Discussion
centers on the distinction between experimentally manipulated public and private self-attention and standards that are adopted
for behavioral self-regulation.
Portions of this study were presented at the annual meeting of the Eastern Psychological Association, New York, April 1991. 相似文献
113.
The disambiguation of threat/neutral homophones was investigated in high- and low-trait anxiety subjects who had been exposed
to either a positive or a negative mood manipulation procedure. Subjects were required first to spell each auditorily presented
word and second, to generate and speak a sentence using the word. Difference indices were calculated for the spelling and
the sentence usage data, i.e. the number of threat minus neutral interpretations. Examination of these indices revealed that
subjects exposed to the negative mood manipulation procedure produced relatively more threat than neutral interpretations
(for both spelling and sentence usage) than did subjects exposed to the positive mood manipulation procedure. Multiple regression
analyses revealed that both the trait anxiety and mood manipulation variables contributed significantly to the prediction
of the difference index on the spelling task. In the analysis of the use of homophones in sentences, only the mood manipulation
variable contributed significantly to the prediction of the difference index on the sentence usage task. 相似文献
114.
This study investigated the psychological and physical health status of 265 crew members on two U.S. Navy ships (a guided
missile cruiser and a frigate on convoy escort duty for tankers under U.S. flag) during the Persian Gulf conflict at four
time periods during combat-ready operations on a single day. Findings suggest that adaptation occurs to extreme stressors
associated with sustained operations. Suggestions are made relative to measures that may minimize psychological and physical
conditions that adversely affect performance under conditions of heavy stress.
Report No. 89-18, supported by the Naval Medical Research and Development Command, Bethesda MD, Department of the Navy, under
research Work Unit No. 63206N.M0096. The opinions expressed in this paper are those of the author and do not reflect the official
policy or position of the Department of the Navy, Department of Defense, nor the U.S. Government. 相似文献
115.
Eye-hand coordination was investigated during a task of finger pointing toward visual targets viewed through wedge prisms. Hand and eye latencies and movement times were identical during the control condition and at the end of prism exposure. A temporal reorganization of eye and hand movements was observed during the course of adaptation. During the earlier stage of prism exposure, the time gap between the end of the eye saccade and the onset of hand movement was increased from a control time of 23 to 68 msec. This suggests that a time-consuming process occurred during the early prism-exposure period. The evolution of this time gap was correlated with the evolution of pointing errors during the early stage of prism exposure, in such a way that both measures increased at the onset of prism exposure and decreased almost back to control values within about 10 trials. However, spatial error was not entirely corrected, even late in prism exposure when the temporal organization of eye and hand had returned to baseline. These data suggest that two different adaptive mechanisms were at work: a rather short-term mechanism, involved in normal coordination of spatially aligned eye and hand systems, and a long-term mechanism, responsible for remapping spatially misaligned systems. The former mechanism can be strategically employed to quickly optimize accuracy in a situation involving misalignment, but completely adaptive behavior must await the slower-acting latter mechanism to achieve longterm spatial alignment. 相似文献
116.
Delay-reduction theory states that the effectiveness of a stimulus as a conditioned reinforcer may be predicted most accurately by the reduction in time to primary reinforcement correlated with its onset. We review support for the theory and then discuss two new types of experiments that assess it. One compares models of choice in situations wherein the less preferred outcome is made more accessible; the other investigates whether frequency of conditioned reinforcement affects choice beyond the effect exerted by frequency of primary reinforcement. 相似文献
117.
Unit price as a useful metric in analyzing effects of reinforcer magnitude. 总被引:7,自引:6,他引:1 下载免费PDF全文
R J DeGrandpre W K Bickel J R Hughes M P Layng G Badger 《Journal of the experimental analysis of behavior》1993,60(3):641-666
In this paper, we applied the behavioral-economic concept of unit price to the study of reinforcer magnitude in an attempt to provide a consistent account of the effects of reinforcer magnitude on behavior. Recent research in the experimental analysis of behavior and in behavioral pharmacology suggests that reinforcer magnitude interacts with the schedule of reinforcement to determine response rate and total consumption. The utility of the unit-price concept thus stems from its ability to quantify this interaction as a cost-benefit ratio (i.e., unit price = characteristics of the schedule of reinforcement divided by magnitude of reinforcement). Research employing the unit-price concept has shown that as unit price increases, a positively decelerating function exists for consumption (i.e., a function with an increasingly negative slope, when plotted on log coordinates) and a bitonic function exists for response rate. Based on these findings, the present analysis applied the unit-price concept to those studies of reinforcer magnitude and drug self-administration that examined the effects of reinforcer magnitude on response rate using simple schedules of reinforcement (e.g., fixed-ratio schedule). This resulted in three findings: (a) Reinforcer-magnitude manipulations and schedule manipulations interact in a manner that can be quantified in terms of unit price as benefit and cost factors, respectively; (b) different reinforcer-magnitude manipulations are functionally interchangeable as benefit factors in the unit-price ratio; and (c) these conclusions appear warranted despite the differences in reinforcers (food or drug), species (dogs, monkeys, or rats), and schedules (interval or ratio), and despite the fact that these studies were not designed for a unit-price analysis. In methodological terms, these results provide further evidence that employing the unit-price concept is a parsimonious method for examining the effects of reinforcer magnitude. In theoretical terms, these results suggest that a single process may underlie the effect of combined reinforcer-magnitude and schedule manipulations. 相似文献
118.
TEMPORAL CONTROL ON INTERVAL SCHEDULES: WHAT DETERMINES THE POSTREINFORCEMENT PAUSE? 总被引:1,自引:1,他引:0 下载免费PDF全文
N K Innis S K Mitchell J E Staddon 《Journal of the experimental analysis of behavior》1993,60(2):293-311
On fixed-interval or response-initiated delay schedules of reinforcement, the average pause following food presentation is proportional to the interfood interval. Moreover, when a number of intervals of different durations occur in a programmed cyclic series, postreinforcement pauses track the changes in interval value. What controls the duration of postreinforcement pauses under these conditions? Staddon, Wynne, and Higa (1991), in their linear waiting model, propose control by the preceding interfood interval. Another possibility is that delay to reinforcement, signaled by a key peck and/or stimulus change, determines the subsequent pause. The experiments reported here examined the role of these two possible time markers by studying the performance of pigeons under a chained cyclic fixed-interval procedure. The data support the linear waiting model, but suggest that more than the immediately preceding interfood interval plays a role in temporal control. 相似文献
119.
The theoretical distinction between an articulatory control process and a short-term phonological store was supported in five experiments on immediate serial recall. In Experiment 1, articulatory suppression during the presentation and recall of auditory material abolished the word length effect but not the phonemic similarity effect. In Experiment 2, the two latter effects were found to be independent with auditory presentation. In Experiment 3, the effects of irrelevant speech and word length were found to be independent with visual presentation. In Experiment 4, articulatory suppression during the presentation and recall of auditory material abolished the phonemic similarity effect with a slow presentation rate. Nevertheless, in Experiment 5, articulatory suppression with a conventional presentation rate did not reduce the effect of phonemic similarity, even when a 10-sec interval was interposed between presentation and recall. These results indicate that the encoding, maintenance, and retrieval of spoken material within the phonological store do not depend on a process of articulatory rehearsal. 相似文献
120.
Choice between delayed reinforcers and fixed-ratio schedules requiring forceful responding. 总被引:1,自引:1,他引:0 下载免费PDF全文
This experiment measured pigeons' choices between delayed reinforcers and fixed-ratio schedules in which a force of approximately 0.48 N was needed to operate the response key. In ratio-delay conditions, subjects chose between a fixed-ratio schedule and an adjusting delay. The delay was increased or decreased several times a session in order to estimate an indifference point--a delay duration at which the two alternatives were chosen about equally often. Each ratio-delay condition was followed by a delay-delay condition in which subjects chose between the adjusting delay and a variable-time schedule, with the components of this schedule selected to match the ratio completion times of the preceding ratio-delay condition. The adjusting delays at the indifference point were longer when the alternative was a fixed-ratio schedule than when it was a matched variable-time schedule, which indicated a preference for the matched variable-time schedules over the fixed-ratio schedules. This preference increased in a nonlinear manner with increasing ratio size. This nonlinearity was inconsistent with a theory that states that indifference points for both time and ratio schedules can be predicted by multiplying the choice response-reinforcer intervals of the two types of schedules by different multiplicative constants. Two other theories, which predict nonlinear increases in preference for the matched variable-time schedules, are discussed. 相似文献