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121.
Signalled free-operant avoidance of shock by pigeons pecking a key   总被引:1,自引:1,他引:0       下载免费PDF全文
Two pigeons were trained to peck a key under a free-operant avoidance schedule. Then, changes in key color signalled the beginning (safe period) and the end (warning period) of the response-shock interval, with a response required to change the key color. Finally, a change in key color signalled the warning period and either a response or a shock reinstated the safe stimulus. During signalled avoidance, response rate was higher during the warning stimulus than during the safe stimulus. More responding tended to occur in the warning stimulus when it was terminated by either a response or a shock than by only a response. In either procedure, response latency during the warning stimulus was a function of the duration of the warning stimulus. In general, response and shock rate were higher during unsignalled than during signalled avoidance. When the warning stimulus was brief, the results were similar to those of unsignalled avoidance. These results confirm previous findings with pigeons, are in general agreement with data provided by other species in studies of signalled avoidance, and thereby indicate the transituationality of the key-pecking operant.  相似文献   
122.
The authors report their experience with a special form of psychodrama for the treatment in small groups of neurotic children aged five to fifteen. The acting out of ambivalent, partly unconscious and restrained tendencies and inclinations by playing, i.e., by taking roles in spontaneous performances, is followed by alternation of identification in the group and, possibly, careful indirect verbalization by the therapeutist and/or group, of which the purpose is to arrive at a reorientation of the attitudes of patients and a consolidation of the newly won attitude.  相似文献   
123.
The electronic structures of anionic, imidic and amidic forms of sulphonamides were investigated and compared by means of I.R., Raman and U.V. spectroscopy. Indices reflecting the electronic situation of the common moiety p-H2N-C6H4-SO2 was a whole, although not necessarily related, physically, to any event taking place in the biological processes, were found to correlate with the in vitro bacteriostatic activity of the specific individual forms. The influence of N1-substituents both on the SO2 electronic features and on the coupling between the para amino group and the phenyl ring was discussed. It resulted that the most active chemical species, in this class of compounds, are characterized, electronically, by the most electron-rich common moiety and, in particular, by the most negative oxygens in the SO2 group and the most available (less engaged) lone-pair in the rho-amino group. These conclusions give a new settlement both to the problem of resonance and to the relation between resonance effects and bacteriostatic activity in this class of compounds.  相似文献   
124.
This paper can be treated as a simplification of the Gentzen formalization of SCI-tautologies presented by A. Michaels in [1].Allatum est die 20 Aprilis 1974  相似文献   
125.
The purpose of this paper is to present a new electromagnetic device which uses alternating magnetic fields for tracking movements of multiple points inside and outside the vocal tract. It is biologically safe, noninvasive, it does not interfere with speech movements, allows for multiple recording in the same subject, and for easy collection of large amounts of data. It is especially suitable for evaluation of patients with speech motor impairments.  相似文献   
126.
127.
Sleep in the dove Zenaida asiatica   总被引:1,自引:0,他引:1  
Electrographic and behavioral observations were made in five adult birds of the genus Zenaida asiatica. Five different vigilance states were quantitated: (1) Active waking (Aw) was characterized by constant behavioral activity; the nuchal electromyogram was tonically active with bursts associated to movements. The electroencephalographic pattern was low voltage and high frequency. (2) Quiet waking (Qw) was characterized by diminished behavioral activity and the EEG pattern was similar to that of Aw. (3) Drowsiness (D) was characterized by behavioral calm. Frequency of cerebral activity diminished progressively, but there were short periods of desynchronization corresponding to brief awakenings. (4) Slow wave sleep (SWS); during this period there was behavioral rest and EEG pattern of continuous slow waves and the nuchal EMG was tonically reduced. Spindles of sleep were not observed. (5) Paradoxical sleep (SP), behaviorally characterized by phasic manifestations consisting of noddings originated by rapid falling down of head and bursts of rapid eye movements. EEG activity was like that of waking state. EMG activity was maintained at the same level as during SWS but sometimes it decreased lightly. Total atonie was not observed. Sleep percentages were higher when recordings were done during the nocturnal period.  相似文献   
128.
The present article interprets mindfulness from the point of view of the effects of language and cognition on human action. Relational Frame Theory is described to show how human suffering is created by entanglement with the cognitive networks made possible by language. Mindfulness can be understood as a collection of related processes that function to undermine the dominance of verbal networks, especially involving temporal and evaluative relations. These processes include acceptance, defusion, contact with the present moment, and the transcendent sense of self. Each of these components of mindfulness are targeted in Acceptance and Commitment Therapy, and there is some evidence that they underlie the therapeutic changes induced by this approach. The relation between the present approach to mindfulness and other approaches is discussed.  相似文献   
129.
The treatment of hypochondriacal patients can be conceptualized as taking one of three approaches. These typically address one of the following questions: 1) “Should the patient be preoccupied?” 2) “Why is the patient preoccupied?” 3) “What are the interpersonal consequences of being preoccupied?” Interpersonal Psychotherapy (IPT) is specifically designed to address the last of these questions. IPT focuses on understanding the patient’s real distress, exploring the patient’s maladaptive communications, and modifying those communications so that others are more able to meet the patient’s attachment needs. With a focus on communication in a time-limited frame, fostered by a strong collaborative relationship, IPT appears to be an effective method of reducing hypochondriacal behavior.  相似文献   
130.
The present study examined the role played by protective factors in moderating the effects of risk factors over bullying and victimization in a sample of 679 male adolescents recruited in Italian high schools. Boys’ involvement in bullying revealed that one in three students has bullied others at least sometimes in the previous three months, and one in six has been victimized at the same rate; victimization decreases with age. The family related risk factor (conflicting parents) was positively associated with bullying and with victimization (together with punitive parenting); the same applied for risk factor related to the individual ways of dealing with problems (emotionally oriented coping skills). Protective factors related to the family context (supportive and authoritative parents) and to the individual (problem solving coping skills) were negatively associated to bullying and victimization. Hierarchical regression analyses revealed a moderating effect of supportive parenting on punitive parenting and on emotionally oriented coping strategies in predicting victimization. Problem solving coping strategies helped buffer the negative impact of emotionally oriented coping strategies over bullying. Implications of results for practitioners and for future studies are addressed.  相似文献   
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