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911.
Compared stress, coping, and psychological adjustment in single (divorced or separated) and married mothers and their young adolescent children. Single mothers reported more daily hassles related to economic, family, and personal health problems, and more symptoms of depression, anxiety, and psychoticism. Single mothers also reported using more coping strategies related to accepting responsibility and positive reappraisal. After controlling for level of family income, differences in family hassles and coping strategies remained significant. The two groups did not differ on subtypes of symptoms after controlling for income, but single mothers still reported more total psychological symptoms. No differences were found between children in these two family constellations on maternal reports of emotional/behavioral problems or on children's self-reported emotional/behavioral problems, stressful events, or coping. Implications of these findings for adjustment to life in single-parent families are discussed. 相似文献
912.
913.
Temporal dimensions of consonant and vowel production: an acoustic and CT scan analysis of aphasic speech 总被引:1,自引:1,他引:0
This study explored a number of temporal (durational) parameters of consonant and vowel production in order to determine whether the speech production impairments of aphasics are the result of the same or different underlying mechanisms and in particular whether they implicate deficits that are primarily phonetic or phonological in nature. Detailed analyses of CT scan lesion data were also conducted to explore whether more specific neuroanatomical correlations could be made with speech production deficits. A series of acoustic analyses were conducted including voice-onset time, intrinsic and contrastive fricative duration, and intrinsic and contrastive vowel duration as produced by Broca's aphasics with anterior lesions (A patients), nonfluent aphasics with anterior and posterior lesions (AP patients), and fluent aphasics with posterior lesions (P patients). The constellation of impairments for the anterior aphasics including both the A and AP patients suggests that their disorder primarily reflects an inability to implement particular types of articulatory gestures or articulatory parameters rather than an inability to implement particular phonetic features. They display impairments in the implementation of laryngeal gestures for both consonant and vowel production. These patterns seem to relate to particular anatomical sites involving Broca's area, the anterior limb of the internal capsule, and the lowest motor cortex areas for larynx and tongue. The posterior patients also show evidence of subtle phonetic impairments suggesting that the neural instantiation of speech may require more extensive involvement, including the perisylvian area, than previously suggested. 相似文献
914.
Richard E. Ham 《Journal of Fluency Disorders》1990,15(5-6):305-315
The response of lay persons to pseudostuttering in approximately 200 spontaneous communication situations were reported and evaluated by 24 graduate students in an advanced class in fluency disorders. The students each spent a day as a “stutterer” in all speech contacts. They summarized their pseudostuttering efforts, the perceived auditor reactions, and their own feelings, in each situation. Results indicated that most lay reactions to any stuttering behavior were, at best, neutral or characterized by obvious changes in behavior. Many reactions were overtly and strongly negative. Student reactions were consistently ones of anxiety, fear, the desire to avoid, frustration, and irritation. Feelings of anger and humiliation were common. Discussion of results points out the value of pseudostuttering experience in clinician training, the possible importance of attitude and adjustment consideration in management of clients who stutter, and the apparent failure of (and need for) our profession to educate the lay public about communicative disorders. 相似文献
915.
Richard E. Nisbett 《Motivation and emotion》1990,14(4):255-263
Evolutionary approaches to behavior, so far from indicating that human behavioral patterns must be universal and wired, actually provide us with good reasons for expecting cultural diversity and good tools for showing how it might develop. Even gender-role related behavior may be very plastic. Highly macho male behavior may be an adaptation to dangerous ecological and economic constraints. Similarly, homicide rates differ massively from culture to culture and may be under the control of specificable ecological and economic constraints.Adapted from a symposium talk given at the annual meeting of the Society for Experimental Social Psychology, October 13, 1990, Buffalo, New York. David Buss, Nancy Cantor, and Claude Steele made helpful comments on earlier versions of this paper. 相似文献
916.
This paper re-examines two hypotheses on the ontogeny of hemispheric specialization that long ago fell into disfavor in neuropsychology. It is argued that these hypotheses, equipotentiality and progressive lateralization, may have suffered from misinterpretation that fostered premature acceptance of the developmental invariance view of hemispheric specialization. An alternative view is presented that incorporates both hypotheses within a neurodevelopmental context using anatomical (postmortem) and childhood aphasia data. 相似文献
917.
We present a study wherein a severe Broca's aphasic patient was trained to learn symbols representing both pure transitive and dative predicates--predicates differing in argument structure--in a visually based artificial language (c-ViC). We found a decrease in performance when two symbols, rather than one, were used to depict these "verbs." However, this decrease in performance was more pronounced for symbols representing pure transitive verbs--those that allow only one argument structure--than for symbols representing dative verbs--those that allow two different argument structures. Also, dative "verbs" yielded better performance when they were inserted in more complex, three-argument "sentences" than when they were inserted in two-argument "sentences." The opposite pattern was found for pure transitives. These results are discussed in terms of our claim that argument structure serves as a point of connection between linguistic information and non-linguistic visual information and in terms of the possibility that argument structure entries are shaped by the form in which visual information is parsed. 相似文献
918.
Range and regression, loudness scales, and loudness processing: toward a context-bound psychophysics 总被引:1,自引:0,他引:1
D Algom L E Marks 《Journal of experimental psychology. Human perception and performance》1990,16(4):706-727
How does context affect basic processes of sensory integration and the implicit psychophysical scales that underlie those processes? Five experiments examined how stimulus range and response regression determine characteristics of (a) psychophysical scales for loudness and (b) 3 kinds of intensity summation: binaural loudness summation, summation of loudness between tones widely spaced in frequency, and temporal loudness summation. Context affected the overt loudness scales in that smaller power-function exponents characterized larger versus smaller range of stimulation and characterized magnitude estimation versus magnitude production. More important, however, context simultaneously affected the degree of loudness integration as measured in terms of matching stimulus levels. Thus, stimulus range and scaling procedure influence not only overt response scales, but measures of underlying intensity processing. 相似文献
919.
Benzodiazepine receptor ligand influences on acquisition: suggestion of an endogenous modulatory mechanism mediated by benzodiazepine receptors 总被引:2,自引:0,他引:2
In rats, pretraining ip administration of the central benzodiazepine receptor antagonist, flumazenil (5.0 mg/kg), or of the inverse agonist, n-butyl-beta-carboline-3-carboxylate (BCCB) (0.2 or 0.5 mg/kg), facilitated retention of a step-down inhibitory avoidance task; the central agonists, clonazepam and diazepam (0.4 or 1.0 mg/kg), had an opposite effect, and the peripheral agonist, 4'-chlordiazepam (1.25 or 6.25 mg/kg), was without effect. Pre- but not post-training flumazenil (2.0 mg/kg) blocked the effect of BCCB (0.5 mg/kg), clonazepam (1.0 mg/kg), or diazepam (1.0 mg/kg) given also pretraining. The post-training administration of all of these drugs had no effect on retention of the avoidance task. Flumazenil (5.0 mg/kg) and BCCB (0.5 mg/kg), given before training, enhanced retention test performance of habituation to a buzzer but not of habituation to an open field. In the three tasks studied, none of the drugs used had any appreciable effect on training session parameters. These results suggest that there is an endogenous mechanism mediated by benzodiazepine agonists, sensitive to inverse agonists, that normally down-regulates acquisition of certain behaviors; this mechanism becomes activated only when the tasks involve or occur with a certain degree of stress or anxiety (i.e., inhibitory avoidance or habituation to the buzzer) and not in less stressful or anxiogenic tasks (i.e., habituation to an open field). 相似文献
920.
Cholinergic-dopaminergic interactions in cognitive performance 总被引:1,自引:0,他引:1
Both acetylcholinergic (ACh) and dopaminergic (DA) systems have been found to be crucial for the maintenance of accurate cognitive performance. In a series of studies examining those aspects of cognitive function revealed by the radial-arm maze, we have found that these two neurotransmitter systems interact in a complex fashion. Choice accuracy deficits in the radial-arm maze can be induced by blockade of either muscarinic- or nicotinic-ACh receptors. The choice accuracy deficit induced by blockade of muscarinic receptors with scopolamine can be reversed by the DA receptor blocker, haloperidol. The specific DA D1 blocker SCH 23390 also has this effect, whereas the specific D2 blocker raclopride does not, implying that it is D1 blockade that is critical for reversing the scopolamine effect. On the other hand, the choice accuracy deficit induced by nicotinic blockade with mecamylamine is potentiated by haloperidol. This effect is also seen with the D2 antagonist raclopride, but not with the D1 antagonist SCH 23390, implying that it is the D2 receptor which is important for the potentiation of the mecamylamine effect. The relevance of the D2 receptor for nicotinic actions on cognitive function is emphasized by the finding that the selective D2 agonist LY 171555 reverses the choice accuracy deficit caused by mecamylamine. Nicotinic and muscarinic blockade are synergistic in the deficit they produce. Antagonist doses subthreshold when given alone produce a pronounced impairment when given together. This latter deficit can be reversed by the D2 agonist LY 171555. These studies have outlined the complex nature of ACh-DA interactions with regard to cognitive function. Possible neural circuits for these interactions are discussed. The effectiveness of these selective DA treatments in reversing cognitive deficits due to ACh underactivation suggests a novel approach to treating cognitive dysfunction in syndromes such as Alzheimer's disease. 相似文献