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861.
The purpose of this study was to assess several acoustic features of the voices of 26 parkinsonian patients under two conditions, with and without bilateral chronic stimulation of the subthalamic nucleus (STN) to estimate the effectiveness of this procedure on parkinsonian speech. When compared to unstimulated patients, stimulated patients showed longer duration of sustained vowels, shorter duration of sentences, nonsense words, and pauses, more variable fundamental frequency (f0) in sentences, and more stable f0 during sustained vowels. Relative intensity was unchanged in both conditions. Further acoustic analyses are warranted to clarify the role of STN stimulation on parkinsonian speech.  相似文献   
862.
This functional MRI study examined how people mentally rotate a 3-dimensional object (an alarm clock) that is retrieved from memory and rotated according to a sequence of auditory instructions. We manipulated the geometric properties of the rotation, such as having successive rotation steps around a single axis versus alternating between 2 axes. The latter condition produced much more activation in several areas. Also, the activation in several areas increased with the number of rotation steps. During successive rotations around a single axis, the activation was similar for rotations in the picture plane and rotations in depth. The parietal (but not extrastriate) activation was similar to mental rotation of a visually presented object. The findings indicate that a large-scale cortical network computes different types of spatial information by dynamically drawing on each of its components to a differential, situation-specific degree.  相似文献   
863.
Japanese exhibits two different types of morphological processes. Some morphologically complex predicates are generated within the domain of the lexicon, whereas others are generated outside the domain of the lexicon. An elicited production task involving both types of complex predicates was administered to six Japanese children with specific language impairment (JSLI) and six children with normal language development (JNLD). The JSLI children experienced significant difficulty forming the lexicon-external complex predicates but much less difficulty with the lexicon-internal complex predicates while the performance of the JNLD children exhibited no such asymmetry. These preliminary results suggest that the deficit of SLI affects the ability to construct implicit procedural rules for morphology that are generated outside the lexicon while their lexical operations for morphology that are generated within the domain of the lexicon remain relatively unimpaired.  相似文献   
864.
The large literature on incidental learning relies almost exclusively on laboratory experiments. Whenever researchers have attempted to demonstrate incidental learning of real-world regularities, they have typically failed to show learning. For example, it is well established that people do not learn regularities in everyday objects, such as the left-right orientation of faces on coins, despite a very large exposure to them. In this report, we examine this apparent contradiction. We argue that most studies exploring real-life incidental learning use tests that are not as sensitive to low-confidence information as those traditionally used in laboratory tasks. Using more sensitive measures, we show that it is possible to learn regularities from British and Japanese cultural life as a direct result of exposure to these regularities. Further, confidence measures suggest that although the information may be acquired incidentally, it can be expressed with and without concomitant awareness of that knowledge.  相似文献   
865.
Neurologists and neuropsychologists are aware that aging men are more at risk than women for brain damage, principally because of the well known male-predominant risk for cardiovascular disease and related cerebrovascular accidents. However, a disproportion in prevalence of brain damage between the sexes in childhood may be less suspected. Furthermore, sex-specific risk for other aetiologies of brain damage may be little known, whether in the pediatric or adult populations. Proposals of a sex difference in cognitive recovery from brain damage have also been controversial. Six hundred and thirty five "consecutive" cases with cortical focal lesions including cases of all ages and both sexes were reviewed. Aetiology of the lesion was determined for each case as was postlesion IQ. Risk was highly male prevalent in all age groups, with a predominance of cardiovascular aetiology explaining much of the adult male prevalence. However, several other aetiological categories were significantly male prevalent in juveniles (mitotic, traumatic, dysplasic) and adults (mitotic, traumatic). There was no sex difference in outcome (i.e., postlesion IQ) of these cortical brain lesions for the cohort as a whole, after statistical removal of the influence of lesion extent, aetiology and presence of epilepsy. Mechanisms potentially responsible for sex differences in prevalence, aetiology of brain damage, and recovery, are reviewed and discussed.  相似文献   
866.
When people are presented with backward-masked images of fear-relevant stimuli and only some of these images are paired consistently with electric shocks, they can predict the occurrence of shocks even though they do not consciously know which images they have seen. We postulated that they may use the perception of visceral cues from the conditional fear response to facilitate the prediction of shocks. In this study, ability to detect heartbeats was used to index sensitivity to visceral cues. The results showed that subjects who could detect their heartbeats performed better than chance in predicting whether or not they would receive a shock during the conditioning task. The findings support the notion that hunches, or "gut feelings," are based in part on the perception of visceral cues.  相似文献   
867.
Following leads from differential emotions theory and empirical research, we evaluated an index of emotion knowledge as a long-term predictor of positive and negative social behavior and academic competence in a sample of children from economically disadvantaged families ( N = 72). The index of emotion knowledge represents the child's ability to recognize and label emotion expressions. We administered control and predictor measures when the children were 5 years old and obtained criterion data at age 9. After controlling for verbal ability and temperament, our index of emotion knowledge predicted aggregate indices of positive and negative social behavior and academic competence. Path analysis showed that emotion knowledge mediated the effect of verbal ability on academic competence. We argue that the ability to detect and label emotion cues facilitates positive social interactions and that a deficit in this ability contributes to behavioral and learning problems. Our findings have implications for primary prevention.  相似文献   
868.
The purpose of the present study was to determine whether exposure to amphetamine during the preweanling period would impact the learning or reward processes of rats tested in adulthood. In three experiments we examined whether amphetamine treatment (0-10 mg/kg per day) on postnatal days 11-17 altered the subsequent performance of adult Sprague-Dawley rats on a step-down passive avoidance, active avoidance, or novelty-seeking task. There was no evidence that postnatal amphetamine exposure affected performance on any of these tasks. These results suggest that the long-term impact of pre- and postnatal psychostimulant exposure differs, because in utero stimulant treatment is known to produce learning deficits and decrease reinforcement efficacy of rats tested in adulthood.  相似文献   
869.
Behavioral assessment: review and prospect   总被引:1,自引:0,他引:1  
In this article I review the history and publication trends of the behavioral assessment (BA) section of the journal, outline future directions for the BA section and suggest avenues for future assessment research. BA began as a stand-alone journal in 1978 and was incorporated as a regular section of Behaviour Research and Therapy (BRT) in 1992. Throughout this article I will use 'BA' to refer to both the stand-alone assessment journal and the assessment section of BRT. Since its inception, the scope of BA has been broad, with behavioral assessment defined to include the assessment of motoric, cognitive, emotional and physiological responses. Several publication trends are identified, including a declining frequency in the number of submitted and published articles on behavioural assessment. This parallels the declining number of assessment articles published elsewhere. Despite these trends, assessment research continues to form a vital foundation for other types of psychological research (e.g. treatment outcome studies), and there is a continued need for assessment-related research. A number of potentially fruitful directions for assessment research are suggested.  相似文献   
870.
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