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851.
A longitudinal study of gender-related cognition and behaviour   总被引:1,自引:0,他引:1  
Gender schema theory proposes that children's acquisition of gender labels and gender stereotypes informs gender-congruent behaviour. Most previous studies have been cross-sectional and do not address the temporal relationship between knowledge and behaviour. We report the results of a longitudinal study of gender knowledge and sex-typed behaviour across three domains in children tested at 24 and 36 months (N = 56). Although both knowledge and sex-typed behaviour increased significantly between 2 and 3 years, there was no systematic pattern of cross-lagged correlations between the two, although some concurrent relationships were present at 24 months. Future longitudinal work might profitably focus on younger children using reliable preverbal measures of gender knowledge and employing a shorter lag between measurement times.  相似文献   
852.
The concept of informed consent was one of the most fruitful ideas that deeply changed the relationships between physicians and their patients from paternalism to respect for the personal autonomy of subjects needing professional medical care. The great progress in medicine, also involving the pharmaceutical industry, has created an increasing need to perform different clinical and experimental trials. The evolution of clinical research in the last decades has influenced strongly the design of these studies. One of the most important changes in this field has been the use of placebo groups in double-blind controlled studies. The controversies have involved not only the use of placebo when standard or proven treatment was available, but also some specific problems concerning the procedure of obtaining informed consent in such trials. This paper briefly presents the evolution of informed consent in Poland as well as different ethical and legal problems concerning informed consent and the use of placebo controls in clinical trials. An earlier version of this paper was presented at an international conference, “Placebo: Its Action and Place in Health Research Today,” held in Warsaw, Poland on 12–13 April, 2003.  相似文献   
853.
Do young infants treat speech as a special signal, compared with structurally similar non‐speech sounds? We presented 2‐ to 7‐month‐old infants with nonsense speech sounds and complex non‐speech analogues. The non‐speech analogues retain many of the spectral and temporal properties of the speech signal, including the pitch contour information which is known to be salient to young listeners, and thus provide a stringent test for a potential listening bias for speech. Our results show that infants as young as 2 months of age listened longer to speech sounds. This listening selectivity indicates that early‐functioning biases direct infants’ attention to speech, granting speech a special status in relation to other sounds.  相似文献   
854.
Neurophysiological experiments with monkeys have demonstrated that working memory (WM) is associated with persistent neural activity in multiple brain regions, such as the prefrontal cortex (PFC), the parietal cortex, and posterior unimodal association areas. WM maintenance is believed to require the coordination of these brain regions, which do not function in isolation but, rather, interact to maintain visual percepts that are no longer present in the environment. However, single-unit physiology studies and traditional univariate analyses of functional brain imaging data cannot evaluate interactions between distant brain regions, and so evidence of regional integration during WM maintenance is largely indirect. In this study, we utilized a recently developed multivariate analysis method that allows us to explore functional connectivity between brain regions during the distinct stages of a delayed face recognition task. To characterize the neural network mediating the on-line maintenance of faces, the fusiform face area (FFA) was defined as a seed and was then used to generate whole-brain correlation maps. A random effects analysis of the correlation data revealed a network of brain regions exhibiting significant correlations with the FFA seed during the WM delay period. This maintenance network included the dorsolateral and ventrolateral PFC, the premotor cortex, the intraparietal sulcus, the caudate nucleus, the thalamus, the hippocampus, and occipitotemporal regions. These findings support the notion that the coordinated functional interaction between nodes of a widely distributed network underlies the active maintenance of a perceptual representation.  相似文献   
855.
Blood-oxygenation-level-dependent signal was measured with functional magnetic resonance imaging in 24 healthy young subjects (12 men and 12 women) during viewing of angry, fearful, and neutral male and female face pictures. Exposure to angry male as opposed to angry female faces activated the visual cortex and the anterior cingulate gyrus significantly more in men than in women. A similar sex-differential brain activation pattern was present during exposure to fearful but not neutral faces. Previous behavioral studies indicate enhanced physiological arousal in men but not in women during exposure to angry male as opposed to female faces, and brain imaging studies have shown that the occipital cortex and the anterior cingulate gyrus are influenced by activity in the autonomic nervous system as well as by visual attention. Hence, we suggest that the elevated occipital and anterior cingulate activation in men during confrontation with other angry and fearful males may reflect enhanced vigilance in a potentially dangerous situation.  相似文献   
856.
Behavioral studies of multisensory integration in motion perception have focused on the particular case of visual and auditory signals. Here, we addressed a new case: audition and touch. In Experiment 1, we tested the effects of an apparent motion stream presented in an irrelevant modality (audition or touch) on the perception of apparent motion streams in the other modality (touch or audition, respectively). We found significant congruency effects (lower performance when the direction of motion in the irrelevant modality was incongruent with the direction of the target) for the two possible modality combinations. This congruency effect was asymmetrical, with tactile motion distractors having a stronger influence on auditory motion perception than vice versa. In Experiment 2, we used auditory motion targets and tactile motion distractors while participants adopted one of two possible postures: arms uncrossed or arms crossed. The effects of tactile motion on auditory motion judgments were replicated in the arms-uncrossed posture, but they dissipated in the arms-crossed posture. The implications of these results are discussed in light of current findings regarding the representation of tactile and auditory space.  相似文献   
857.
Single-unit, event-related potential (ERP), and neuroimaging studies have implicated the prefrontal cortex (PFC) in top-down control of attention and working memory. We conducted an experiment in patients with unilateral PFC damage (n=8) to assess the temporal kinetics of PFC-extrastriate interactions during visual attention. Subjects alternated attention between the left and the right hemifields in successive runs while they detected target stimuli embedded in streams of repetitive task-irrelevant stimuli (standards). The design enabled us to examine tonic (spatial selection) and phasic (feature selection) PFC-extrastriate interactions. PFC damage impaired performance in the visual field contralateral to lesions, as manifested by both larger reaction times and error rates. Assessment of the extrastriate P1 ERP revealed that the PFC exerts a tonic (spatial selection) excitatory input to the ipsilateral extrastriate cortex as early as 100 msec post stimulus delivery. The PFC exerts a second phasic (feature selection) excitatory extrastriate modulation from 180 to 300 msec, as evidenced by reductions in selection negativity after damage. Finally, reductions of the N2 ERP to target stimuli supports the notion that the PFC exerts a third phasic (target selection) signal necessary for successful template matching during postselection analysis of target features. The results provide electrophysiological evidence of three distinct tonic and phasic PFC inputs to the extrastriate cortex in the initial few hundred milliseconds of stimulus processing. Damage to this network appears to underlie the pervasive deficits in attention observed in patients with prefrontal lesions.  相似文献   
858.
This article traces the transformative paradigm shift in the theory and practice of personal change. Within a decade, new conceptual models, analytic methodologies and modes of treatment were created. Treatments were altered in the content, locus, and agents of change. This enterprising period also witnessed a sweeping shift in the public acceptance of behaviorally oriented treatments. The present article also analyzes the evolving theorizing and applications of social cognitive theory rooted in modeling, self-regulatory, and self-efficacy mechanisms of psychosocial change. This model of change is implemented from an agentic perspective to promote personal, institutional, and society-wide changes that address some of the most urgent global problems.  相似文献   
859.
Psychoanalytic psychotherapy in clinical practice is traditionally a long-term treatment conducted by well-trained psychotherapists. However, very few studies have been published that evaluate the effects of such treatment. To redress this lack of studies, 55 individuals selected for long-term psychoanalytic psychotherapy (average, 3 years) were invited to participate in a naturalistic study. The psychotherapists had a mean of 15 years of professional experience. The 36 patients who completed psychotherapy manifested a substantial reduction in symptomatic suffering and decreased levels of character pathology, as measured by the Karolinska Psychodynamic Profile (KAPP) and the Karolinska Scales of Personality. Generally, such changes were not found in the individuals who did not engage in treatment. In the therapy group, improvements were found on eight KAPP subscales defining different aspects of character: Intimacy and Reciprocity, Frustration Tolerance, Regression in the Service of the Ego, Coping with Aggressive Affects, Conceptions of Bodily Appearance and their Significance for Self-esteem, Sexual Function, Sexual Satisfaction, and Personality Organization. The results indicate that individuals who engaged in psychotherapy improved their capacity to handle crucial aspects of life and reduced their symptomatic suffering.  相似文献   
860.
As the Internet has changed communication, commerce, and the distribution of information, so too it is changing psychological research. Psychologists can observe new or rare phenomena online and can do research on traditional psychological topics more efficiently, enabling them to expand the scale and scope of their research. Yet these opportunities entail risk both to research quality and to human subjects. Internet research is inherently no more risky than traditional observational, survey, or experimental methods. Yet the risks and safeguards against them will differ from those characterizing traditional research and will themselves change over time. This article describes some benefits and challenges of conducting psychological research via the Internet and offers recommendations to both researchers and institutional review boards for dealing with them. ((c) 2004 APA, all rights reserved)  相似文献   
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