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991.
It is shown that lexical decision times to strong associates with an associative strength of approximately 40% are facilitated relative to targets following a neutral prime, “blank,” whereas very weak associates with an associative strength of less then 3% are neither facilitated nor inhibited. It is also shown that relative to the “blank” baseline time, a row of crosses inhibits processing of the following target. The latter finding has implications for earlier studies that have used crosses as a neutral prime. In these studies, facilitation effects have been overestimated and inhibition effects have been underestimated. Neely 1976 has proposed a predict-and-match strategy according to which subjects are assumed to predict one or more targets from the prime and to match the actual target onto the predicted targets. A part of this theory is not supported by the present data. The results are discussed in terms of the two-process theory of expectancy (Posner & Snyder, 1975). They are also considered in the light of a recent theory by Becker (1980). As an alternative interpretation of part of the reported data, a coherence assumption by the subjects about all reading materials is introduced.  相似文献   
992.
Premenstrual syndrome is a condition with cyclical mood changes occurring in 30 % of the female population of fertile ages. The symptom development is very closely related to the luteal phase indicating the existence of one or more factors during the luteal phase that provoke mental symptoms in sensitive patients. This is further supported by the fact that hysterectomized women with no menstrual bleedings but with the ovarian hormone cycle continue to show cyclical mood changes without having the cycle phase. The nature of the symptom provocating factor is still unknown but the ovarian hormones progesterone and/or estradiol are suspected. This as certain women taking oral contraceptives and sequential postmenopausal estrogen-progestagen treatment achieve mood changes. Psychological and personality factors are probably also involved, at least in the degree of the mood change and the type of mood experienced.  相似文献   
993.
The role of noradrenaline in learned behaviors: studies using DSP4   总被引:1,自引:0,他引:1  
DSP4 (N-2-chloroethyl-N-ethyl-2-bromobenzylamine) is a novel noradrenaline (NA) neurotoxin sufficiently selective, following systemic administration, to be a pharmacological tool of much potential; this possibility has warranted the extensive use of DSP4 to study the role of noradrenaline in learned behaviors. Thus, after DSP4 treatment (50 mg/kg) a very robust two-way active avoidance impairment is incurred and this deficit remained over a wide range of stimulus conditions and parameters. On the other hand, the acquisition of relatively simple tasks such as one-way active avoidance, fear conditioning, step-down passive avoidance and taste-aversion conditioning, was only slightly affected or not affected at all. DSP4 administration caused a retardation of the rate of acquisition of a "right-turn" running response for food reward in a modified T-maze, and an attenuation of the exteroceptive context effect in taste-aversion conditioning and extinction. In spite of a few similar results, NA-depletions following DSP4 generally do not produce the same behavioral effects as the 6-Hydroxydopamine lesions but are more akin to the locus coeruleus lesion. An hypothesis of the role of central NA, based mainly upon the shuttle box procedure, incorporates a function in establishing the Signal-Response association, in adapting to situations that require a correct response to stress and in maintaining an adequate span of attention to the range of environmental events presented in any given learning situation.  相似文献   
994.
Unreliable probabilities,risk taking,and decision making   总被引:7,自引:0,他引:7  
  相似文献   
995.
Two experiments examined the relations among self-esteem, perceived competency to cope, and actual coping behaviors following a threat communication. Leventhal's “parallel response model” (in Advances in experimental social psychology, L. Berkowitz (Ed.), New York: Academic Press, 1970, Vol. 5) predicts that low-esteem subjects will show deficits in both competency and coping behaviors. Experiment 1 manipulated threat level of a tetanus communication. Low-esteem subjects showed coping deficits on measures of free associations, free recall, fatalism, and coping. Threat groups differed only on fear and danger measures. Experiment 2 manipulated the fear level of an antismoking film and used false feedback to alter perceived competency. Positive feedback increased perceived competency to quit smoking among low-esteem subjects only. Without feedback, low-esteem subjects reduced smoking less than high-esteem subjects; positive feedback reversed the pattern. The discussion argued that, consistent with Leventhal's model, the low-esteem coping deficit has two independent causes: (1) excessive concern with fear, and (2) inadequate perceived competency.  相似文献   
996.
Early infantile autism was found to be associated with an atypical pattern of cerebral lateralization. Based on EEG measures of hemispheric activation during cognitive processing, it was found that 7 of the 10 autistic individuals tested showed a pattern of hemispheric specialization rarely seen in the normal population; namely, a “reversal” in lateralization reflective of a lack of left-hemisphere specialization for linguistic functions. Furthermore, the autistic individuals' pattern of cognitive strengths and weakness is suggestive of a selective impairment of the left cerebral hemisphere.  相似文献   
997.
Within the last few years, considerable attention has been devoted to the possibility that the amelioration of stuttering in many novel speaking conditions is a function of vocal changes with or without accompanying modifications in prosodic expression. These formulations have made reference primarily to conditions in which stutterers were induced into one or another novel speech pattern by an external stimulus such as masking noise, a rhythmic cue, or by instructions to sing, or read in unison with another speaker. In contrast, far less attention has been paid to other ameliorative conditions that lack a novel external stimulus or special instructions that direct the stutterer to speak in some unique manner. Speaking or reading to a child is an example of this latter type of condition. The present study was conducted to see if nine adult stutterers and a matched group of nonstutterers would evince vocal changes as they read aloud to another adult, a child, and a child and adult together. There was also a fourth control condition wherein the subjects read to one of the experimenters. Dependent measures of disfluency and stuttering, fundamental frequency, fundamental frequency deviation, fluent reading rate, and peak vocal sound pressure level were made and treated statistically. The major findings of this study indicated that, relative to the control condition, both subject groups exhibited several vocal changes when reading to a child alone and to a child and adult together. In addition, the stutterers experienced a reduction in disfluency, but only when reading to the child alone. The normal speakers exhibited too few disfluencies in the control condition for any meaningful change to occur in that dependent variable. The fact that the stutterers evinced vocal changes in both experimental conditions but a significant drop in disfluency in just one bears importantly on hypotheses that emphasize vocal changes in conditions that ameliorate stuttering.  相似文献   
998.
Two experiments examined alternative explanations for the Scheier and Carver(1977) results linking self-focused attention to increased responsivity to emotional stimuli. In both studies autonomic, expressive, and self-report measures of emotional arousal failed to confirm the earlier findings. An individual difference measure reported by others to parallel the effects of situationally manipulated self-attention also failed to confirm the previously reported findings. Though in direct contradiction to Scheier and Carver's results, the results are consistent with a facial feedback hypothesis and with previous findings on the effects of expressive inhibition on self-reports of emotional arousal.This research was supported in part by NSF grant 77-08926 to the first author and by NIMH grant MH 29446 to the third author, as well as by funds from the Lincoln Filene Endowment to Dartmouth College.  相似文献   
999.
An 8-month-old infant with a developmental quotient of 112 months was given response-contingent stimulation using a pressure-sensitive pillow which turned an overhead mobile. The subject learned to control the mobile by kicking the pillow, and concurrently began smiling at both the mobile and her mother for the first time. After mastering three contingencies on arm, head, and leg movement, she displayed what appeared to be a Piagetian coordinated secondary circular reaction, in which one response provided 4 seconds of access to another contingency. Although the subject remains severely retarded, the results suggest that some forms of developmental delay may be treated at least in part as a failure to develop contingency awareness.  相似文献   
1000.
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