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251.
The possibility of isolating personality types using 16 PF profiles was studied by utilizing a Q-type factor analytic procedure. Four modal profiles, characteristic of major clusters of subjects, were derived and cross validated. These four major types successfully classified approximately 2/3 of the 16 PF protocols (n = 1037), and classified similar proportions of previously published profiles. Variation of classification rates as a function of race and sex was described, and strategies for utilizing the profiles for research and interpretive purposes were outlined.  相似文献   
252.
Two experiments were carried out to investigate whether visual imagery was used in representing transitive linear ordering relationships. Subjects were presented with passages describing either a linear ordering or a set inclusion relationship, while being subjected to either visual or verbal interference. Performance was tested by asking subjects to judge the truth or falsity of statements concerning both the information presented in the passages and inferences that could be drawn from this information. In neither experiment was there any evidence for the linear ordering material being selectively disrupted by the visual interference task, as would have been predicted by the imagery theory. Thus it is concluded that linear orderings are probably not represented as visual images.  相似文献   
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254.
Nineteen agoraphobic outpatients were randomly assigned to four sessions of either (1) Exposure: planning and discussion of exposure homework tasks requiring patients to enter and remain in phobic situations hitherto avoided; or (2) Control: discussion of marital, family and social difficulties and strategies for dealing with these.A small but significant effect was found at post-test and at one month follow-up in favour of the exposure condition. It is suggested that this variable should be controlled in future relevant experiments and is worth including as an inexpensive expedient of active treatment of phobias.  相似文献   
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256.
Research suggests that kinesthetic aftereffect (KAE) scores reflect status on a postulated stimulus intensity modulation (SIM) mechanism that damps down subjective stimulus intensity for some (reducing) and increases it for others (augmenting). Such a mechanism would help account for empirically observed individual differences in such behaviors as pain tolerance, sensory deprivation reactivity, and stimulation seeking. It was hypothesized and confirmed in three adult female samples that KAE varies curvilinearly over the menstrual cycle: Greater KAE reduction occurs at the cycle's beginning and end. Neither tiredness, oral contraception, medication, attention, nor social expectations can explain this finding. Of the behaviors studied in the KAE literature, only five are also encompassed by the menstrual cycle literature. Four of these (antisocial behavior, acute schizophrenic episodes, accidents, and activity level) show similar curvilinearity over the cycle. We hypothesize that cyclical variation in the SIM mechanism mediates the curvilinear pattern observed for both these four behaviors and KAE.  相似文献   
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258.
Five pigeons were trained on concurrent variable-interval schedules. A series of conditions in which the ratio of reinforcement rates on two keys was progressively increased and then decreased was arranged twice. The birds were then exposed to an irregular sequence of conditions. Each condition in which reinforcement was available on both keys lasted six sessions. Performance in the first, third, and sixth sessions after a condition change was analyzed. Following a condition change, preference was biased toward the preference in the last condition, but this effect largely disappeared before the sixth session of training. The birds' preferences also appeared less sensitive to reinforcement rates in early sessions after a transition. Preference in a session was a function of both the reinforcements in that session and the reinforcements obtained in as many as four or five previous sessions. The effects of reinforcements in previous sessions could be summarized by the performance in the immediately preceding session, giving a relatively simple relation between present performance and a combination of present reinforcement and prior session performance. While such hysteresis could cause undermatching when only a small number of sessions are arranged in a condition, undermatching in a stable-state performance probably arises elsewhere.  相似文献   
259.
Because carbon monoxide (CO) is an easily understood danger of cigarette smoking, new breath CO analyzers may be useful in cessation programs. Self-reported cigarette consumption and breath CO correlated .70 using a 90-sec. CO-determination method. Smokers averaging 17 daily cigarettes had average breath CO of 24 parts per million (ppm), falling to 7.71 ppm for smokers claiming at least 24-hr. abstinence. Corresponding carboxyhemoglobin (COHb) estimates were 4.34% (slightly above World Health Organization 4% safety limit) and 1.39%. Smoking clinics can use CO-monitoring devices for feedback or surveillance, although feedback would provide the most benefits for participants.  相似文献   
260.
This study investigated the relationship between life stress and measures of anxiety, depression, and hostility as a function of subjects' arousal-seeking status. Results indicated significant relationships between negative life change and measures of both anxiety and hostility. These relationships, however, held only for subjects who were low on the arousal-seeking dimension. The results suggest that arousal-seeking status may serve as a moderator variable in determining the relationship between life stress and other variables.  相似文献   
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