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The nonrandom distribution of situational fears has been explained by evolutionary survival relevance of specific fears. Thirty-eight stimuli were taken from the literature on preparedness and were scored on fearfulness, objective dangerousness, and spatiotemporal unpredictability by three separate groups of students. The same items were scored on survival relevance by 15 biologists. Fearfulness of cues significantly correlated not only with survival relevance but also, and even more strongly, with dangerousness and unpredictability. While the fear/survival relevance association virtually disappeared when the unpredictability contribution was partialed out, the fear/unpredictability correlation was only marginally affected when controlling for survival relevance. This suggests that nonrandomness of feared stimuli may result from the spatiotemporal unpredictability that is attributed to these stimuli. The current practice of using snakes and spiders as phobia-relevant, and flowers and mushrooms as neutral, cues was not justified by the ratings of the 15 independent experts.This study was supported in part by a grant from the Dutch Organization for Fundamental Research (ZWO/Psychon, 560-268-001).  相似文献   
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Prior to assuming the upright crouching posture over their pups during nursing bouts, lactating rats typically engage in several oral behaviors, including nuzzling, licking and rearranging pups. By acutely depriving dams of various aspects of perioral stimulation from pups (with anesthesia of the mystacial pads or of the tongue, with mouth suturing, or with muzzling), we found the following: (1) Distal stimulation from pups maintains proximity-seeking behavior, but is insufficient to stimulate nursing behavior. (2) Lack of tongue feedback decreases pup licking and hastens the onset of crouching. (3) Snout, but not tongue, contact with pups is required for hovering over them. (4) The position of the dam while hovering over her litter enables the pups to gain access to her ventrum, thereby provoking her upright, crouching posture. (5) Older pups are capable of bypassing the dam's perioral attentions and stimulating crouching directly by burrowing under the dam's ventrum.  相似文献   
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In comparative anatomical studies of the shoulder, the humeral retractors are often grouped together as propulsive muscles, which are important in the propulsive stroke of the forelimb during quadrupedal locomotion. Electromyographic (EMG) analyses of these muscles in opossums, cats, and dogs in general have confirmed such conclusions. An EMG study of chimpanzee shoulder muscles during knuckle-walking found, however, that the humeral retractors are either inactive or perform a function unrelated to propulsion (Larson & Stern, 1987). This contrast in muscle recruitment patterns between chimpanzees and more "typical" mammalian quadrupeds was attributed to the derived morphology of the chimpanzee shoulder. The present study examines the activity patterns of the humeral retractors in the vervet monkey, a primate more closely resembling nonprimate mammals in its shoulder morphology. The results of this EMG analysis show that despite the significant differences in anatomy between chimpanzees and vervets, the two species display very similar muscle recruitment patterns during quadrupedalism, and there is evidence for this same pattern in other species of primates. These differences in muscle activity patterns between primates and nonprimate mammals may be related to changes in the neurological control of locomotion in primates due to the evolutionary development of manipulative abilities in the primate forelimb.  相似文献   
5.
We use the algebraic theory of programs as in Blikle [2], Mazurkiewicz [5] in order to show that the difference between programs with and without recursion is of the same kind as that between cut free Gentzen type formalizations of predicate and prepositional logics.  相似文献   
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How concerned are primary-school-aged stuttering children about their communication problem? What are the clinical implications of this concern?Fifteen years ago, Silverman (1970) suggested that primary-school-aged children who stuttered were not concerned about their disfluencies. A clinical implication of that report was that the interpreted lack of concern might negatively affect the children's motivation and desire for change in therapy. Scant research exists to support or refute this implication. While research is available on reactions to stuttering, pretherapeutic attitudes—especially those of children—have not been systematically reported. Guitar (1976) measured the pre-treatment attitudes of 38 adult stutterers and reported that, “those stutterers with more negative attitudes measured just prior to treatment, were most likely to have high levels of stuttering a year later, even though all subjects left therapy entirely fluent.” In related areas, research by Kolb, Winter, and Berlen (1968), McFall (1970), and McFall and Hammen (1971) has indicated that clients who are more motivated do better in behavior modification programs.Whether or not these findings may be generalized to children, in the midst of a developmental process, is purely speculative.  相似文献   
8.
Regional cerebral glucose metabolism in aphemia: A case report   总被引:1,自引:0,他引:1  
Local cerebral metabolism was determined in a patient suffering aphemia following cerebral infarction using the 18FDG-PET technique. The syndrome was characterized by profound ictal nonfluency with sparing of other language functions. Speech subsequently improved so that content and grammar were appropriate but mild dysprosody persisted. Conventional CT showed no lesion of the left hemisphere while PET revealed a discrete focus of hypometabolism on the left which partially resolved on serial studies. The metabolic lesion could be localized to the region of the inferior precentral gyrus and the adjacent subcortical space.  相似文献   
9.
This study focuses on Divorce-Prone individuals and the question of why some persons fail in one marriage after another. The authors studied 12 individuals who had each been divorced two or more times. They found that the cases fell into one of three broad and overlapping groups. The groups have been called the Self-Involved Narcissists, the Compliant Depressed, and the Casualties of Life's Vicissitudes. The individuals and the groups demonstrate a different etiology, different treatment problems, and a very different prognosis.  相似文献   
10.
Sutherland and Young's perspective is a timely and rigorous examination of trait impressions based on facial cues. We propose three strtegies to further advance the field: incorporating natural language processing, including diverse facial stimuli, and re-interpreting developmental data.  相似文献   
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