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951.
Two parallel experiments used pigeons in a transfer of control design to determine the basis of the transfer of the use of the “advance strategy” across successive discriminations (W. K. Honig & H. Lindsay, Learning and Motivation, 1975, 6, 157–178). Pigeons were first trained under instrumental contingencies to use an “advance” response to maximize their exposure to SD and minimize their exposure to SΔ. Then orthogonal stimuli (key lights in Experiment 1 and diffuse illuminations in Experiment 2) were independently established through separate discriminative Pavlovian procedures as CS+ and CS? or as CSo's. Later in special tests, it was demonstrated that the associative values of the Pavlovian CS's were a major factor governing the use of the advance strategy: only pigeons exposed to CS+CS? used the advance response to regulate their exposure to either CS. Although these experiments showed that the necessary and sufficient conditions for utilization of the advance strategy are the Pavlovian associative values of the discriminative stimuli, opportunity for differential “operant” responding during the discriminative stimuli seems to be a contributor to the optimal use of the advance response across successive discriminations.  相似文献   
952.
Duration-reduction of avoidance sessions as negative reinforcement   总被引:6,自引:6,他引:0       下载免费PDF全文
Five rats were exposed to a shock-postponement procedure in which responses on each of two levers initially had equivalent effects. After an initial training sequence that ensured at least some responding on each lever, an additional consequence was made conjointly operative on the previously less-preferred lever for each animal. Each response on this lever continued to postpone shock, but also reduced the session duration by one minute. The conjoint contingencies were operative until, through session-shortening responses and the passage of time, the session was scheduled to end in two minutes; during the final two minutes the session-shortening contingency was disabled while the shock-postponement contingency continued to be operative on both levers. When responding shifted to a predominance on the session-shortening lever, the conjoint contingency was shifted to the other lever; for four of the five rats this reversal was followed by two additional reversals. Two of the rats' responding showed clear, strong, and unambiguous sensitivity to the session-shortening contingency. The responding of two others was also systematically controlled by that contingency, but the effects were less clearcut. The fifth animal showed an initial shift when session-shortening was introduced, but its subsequent behavior proved insensitive to reversals of procedure. The results clearly indicate a sensitivity of behavior to events on a time scale quite distinct from that of immediate consequences. They also support an interpretation of avoidance sessions, considered in their entirety, as events whose contingent relationship to behavior can affect that behavior—even in the absence of stimuli that delineate those relationships. Finally, these results support an interpretation of aversively based conditioning within a broader context, analogous to the “open versus closed economy” interpretation of appetitively controlled behavior.  相似文献   
953.
954.
The purpose of the research was to identify empirically and measurably those dimensions considered important by laity in evaluating their priest. The 83-item questionnaire was developed from existing instruments and from an interview survey carried out on laity from a national selection of Episcopal parishes. 221 parishes responded with complete data. A factor analysis was performed on the data yielding eight useable factors: (a) Pastoral sensitivity, (b) Administrative Skills, (c) Scholarship, (d) Personal Integrity, (e) Innovation, (f) Personal Spirituality, (g) Meaningfulness of Services, and (h) Laity Involvement. The results of the research were seen as a beginning insight into what the laity perceived as important aspects of their parish priest's role, and an instrument to measure these dimensions for further research was produced.  相似文献   
955.
956.
The purpose of this study was to assess the perceptions of emotions by accepted and rejected children. Peer ratings and peer sociometrics were used to identify accepted and rejected children. All children were administered a task specifically designed to measure their ability to perceive emotions. This task consisted of a series of videotaped interactions involving two individuals—either two adults or two children—portraying one of three affective states: happiness, sadness, and anger. After viewing each interaction, children were asked to identify what the person was feeling. In addition, teachers and peers rated the children on their ability to perceive emotions in others. The results indicated that accepted children obtained significantly higher scores than rejected children on the identification of emotions in the interactions. Teachers and peers also rated accepted children as better perceivers of emotions than rejected children. Implications of the results are discussed.  相似文献   
957.
It has been suggested that psychopaths exhibit specific deficits in cognitive processes associated with frontal lobe functioning. There is also evidence which indicates that level of intelligence may influence expression of impulse control among psychopaths. The present study investigated these hypotheses by comparing groups of 44 psychopaths and 14 normal controls selected from a sample of incarcerated male felons using Minnesota Multiphasic Personality Inventory (MMPI)-defined criteria. Dependent variables included several measures of cognitive flexibility, perseveration, and impulsiveness. Compared to normal controls, psychopaths showed no greater tendencies to persist in incorrect responding, disregard cues suggesting the need to modify behaviors, or proceed impulsively in problem solving. Level of intelligence was found to be a moderator variable influencing performance for psychopaths and normal controls. Results suggest that deficits in cognitive functioning are not necessarily characteristic of psychopaths across situations.  相似文献   
958.
Few efforts have been made to understand antisocial-prone individuals who maintain adaptive functioning. This study identified a sample of potentially deviant but adaptively functioning persons to determine whether they differed significantly from their more conforming peers. A small sample of men was selected by Minnesota Multiphasic Personality Inventory (MMPI)-defined criteria for sociopathy and compared with MMPI-defined normals of similar ages, backgrounds, and intelligence. Response variables were those cited in the literature as characteristic of sociopathic psychopathology and included measures of abilities to plan ahead and inhibit impulsiveness, sensation seeking, interpersonal performance and style, and behavior conformity. Men labeled adaptive sociopaths showed greater impulsiveness and needs for experience seeking, earned lower scores on measures of socialization and self-control, and admitted greater adolescent behavior deviance. They were not shown to be less empathetic or less able to relate interpersonally in interview. The potential role of socially constructive self-determined goals and tangible vocational rewards as mediators of adaptive behavior are discussed in terms of overcoming antisocial tendencies and attenuation of behavior disinhibition.  相似文献   
959.
The Ponzo illusion refers to an apparent change in length of objectively equal parallel lines induced by enclosure within an acute angle. The present study investigated this illusory change in stimulus extent as a function of the relative depth positions of the parallel lines and the inducing angle. To permit facile and unconfounded manipulation of apparent depth, the stimuli comprising the Ponzo configuration were stereoscopic contours formed from dynamic random-element stereograms. The main results were: (1) apparent depth separation exerted a strong influence on illusion magnitude; (2) this influence was asymmetrical in that illusion magnitude decreased when the inducing angle appeared in depth behind the parallel lines and increased when the inducing angle appeared in depth in front of the lines. These data are consistent with a general theory of space perception that assumes that information about depth position is processed prior to information about stimulus characteristics.  相似文献   
960.
Latent trait models for binary responses to a set of test items are considered from the point of view of estimating latent trait parameters=( 1, , n ) and item parameters=( 1, , k ), where j may be vector valued. With considered a random sample from a prior distribution with parameter, the estimation of (, ) is studied under the theory of the EM algorithm. An example and computational details are presented for the Rasch model.This work was supported by Contract No. N00014-81-K-0265, Modification No. P00002, from Personnel and Training Research Programs, Psychological Sciences Division, Office of Naval Research. The authors wish to thank an anonymous reviewer for several valuable suggestions.  相似文献   
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