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971.
Lisanby SH Morales O Payne N Kwon E Fitzsimons L Luber B Nobler MS Sackeim HA 《CNS spectrums》2003,8(7):529-536
New findings regarding the mechanisms of action of electro-convulsive therapy (ECT) have led to novel developments in treatment technique to further improve this highly effective treatment for major depression. These new approaches include novel placements, optimization of electrical stimulus parameters, and new methods for inducing more targeted seizures(eg, magnetic seizure therapy [MST]). MST is the use of transcranial magnetic stimulation to induce a seizure. Magnetic fields pass through tissue unimpeded, providing more control over the site and extent of stimulation than can be achieved with ECT. This enhanced control represents a means of focusing the treatment on target cortical structures thought to be essential to antidepressant response and reducing spread to medial temporal regions implicated in the cognitive side effects of ECT. MST is at an early stage of development. Preliminary results suggest that MST may have some advantages over ECT in terms of subjective side effects and acute cognitive functioning. Studies designed to address the antidepressant efficacy of MST are underway. As with all attempts to improve convulsive therapy technique, the clinical value of MST will need to be established through controlled clinical trials. This article reviews the experience to date with MST, and places this work in the broader context of other means of optimizing convulsive therapy in the treatment of depression. 相似文献
972.
Schmitt DP Alcalay L Allik J Ault L Austers I Bennett KL Bianchi G Boholst F Cunen MA Braeckman J Brainerd EG Caral LG Caron G Casullo MM Cunningham M Daibo I De Backer C De Souza E Diaz-Loving R Diniz G Durkin K Echegaray M Eremsoy E Euler HA Falzon R Fisher ML Foley D Fry DP Fry S Ghayur MA Golden DL Grammer K Grimaldi L Halberstadt J Herrera D Hertel J Hoffmann H Hooper D Hradilekova Z Hudek-Kene-evi J Jaafer J Jankauskaite M Kabangu-Stahel H Kardum I Khoury B Kwon H Laidra K Laireiter AR 《Journal of personality and social psychology》2003,85(1):85-104
Evolutionary psychologists have hypothesized that men and women possess both long-term and short-term mating strategies, with men's short-term strategy differentially rooted in the desire for sexual variety. In this article, findings from a cross-cultural survey of 16,288 people across 10 major world regions (including North America, South America, Western Europe, Eastern Europe, Southern Europe, Middle East, Africa, Oceania, South/Southeast Asia, and East Asia) demonstrate that sex differences in the desire for sexual variety are culturally universal throughout these world regions. Sex differences were evident regardless of whether mean, median, distributional, or categorical indexes of sexual differentiation were evaluated. Sex differences were evident regardless of the measures used to evaluate them. Among contemporary theories of human mating, pluralistic approaches that hypothesize sex differences in the evolved design of short-term mating provide the most compelling account of these robust empirical findings. 相似文献
973.
In this report, we have analyzed the effects of left and right STN stimulation separately on different aspects of speech. Significant differences were found between left and right stimulation. It appears that selective left-sided stimulation has a profoundly negative effect on prosody, articulation and hence intelligibility. Right-sided stimulation does not display this side-effect. There is no significant difference in speech characteristics between bilateral stimulation on and off. We suggest that a balanced tuning of bilateral basal ganglia networks is necessary for speech, and that the left circuit is probably dominant. 相似文献
974.
Allen RS Burgio LD Roth DL Ragsdale R Gerstle J Bourgeois MS Dijkstra K Teri L 《Psychology and aging》2003,18(4):886-895
Confirmatory factor analysis of the Revised Memory and Behavior Problems Checklist--Nursing Home (RMBPC) replicated the factor structure of the community-based RMBPC (L. Teri et al., 1992). The reliability of the total score was high as indexed by estimates of internal consistency (alpha = .95), test-retest reliability (r = .86), and interrater reliability between 2 interviewers (r = .88). Notably, the interrater reliability between 2 independent certified nursing assistants (CNAs) regarding residents' behavior problem frequency was more modest (r = .46), possibly reflecting the degree to which resident behaviors capture individual CNA's attention. This may have implications for the interpretation of data from the Minimum Data Set. CNAs reported moderately severe burden associated with behavior problems in 47% of residents under their care. 相似文献
975.
De Bruin NM Kiliaan AJ De Wilde MC Broersen LM 《Neurobiology of learning and memory》2003,80(1):63-79
Rationale. Hypertension is considered a risk factor for the development of cognitive disorders, because of its negative effects on cerebral vasculature and blood flow. Genetically induced hypertension in rats has been associated with a range of cognitive impairments. Therefore, spontaneously hypertensive rats (SHR) can potentially be used as a model for cognitive deficits in human subjects. Consecutively, it can be determined whether certain food components can improve cognition in these rats. Objective. The present study aimed to determine whether SHR display specific deficits in attention, learning, and memory function. Additionally, effects of chronic uridine and choline administration were studied. Methods. 5-7 months old SHR were compared with normotensive Wistar-Kyoto (WKY) and Sprague-Dawley (SD) rats. (a) The operant delayed non-matching-to-position (DNMTP) test was used to study short-term memory function. (b) The five-choice serial reaction time (5-CSRT) task was used to assess selective visual attention processes. (c) Finally, the Morris water maze (MWM) acquisition was used as a measure for spatial learning and mnemonic capabilities. Results. (1) SHR exhibited significantly impaired performance in the 5-CSRT test in comparison with the two other rat strains. Both the SHR and WKY showed deficits in spatial learning when compared with the SD rats. (2) Uridine and choline supplementation normalized performance of SHR in the 5-CSRT test. (3) In addition, uridine and choline treatment improved MWM acquisition in both WKY and SHR rats. Conclusion. The present results show that the SHR have a deficiency in visual selective attention and spatial learning. Therefore, the SHR may provide an interesting model in the screening of substances with therapeutic potential for treatment of cognitive disorders. A combination of uridine and choline administration improved selective attention and spatial learning in SHR. 相似文献
976.
Berlin CI Hood L Morlet T Rose K Brashears S 《Mental retardation and developmental disabilities research reviews》2003,9(4):225-231
Auditory brainstem responses (ABRs) and otoacoustic emissions (OAEs) are objective measures of auditory function, but are not hearing tests. Normal OAEs reflect normal cochlear outer hair cell function, and an ABR indicates a synchronous neural response. It is quite possible for a patient to have normal OAEs but absent or grossly abnormal ABR and a behavioral audiogram that is inconsistent with either test. These patients, who may constitute as much as 10% of the diagnosed deaf population, have auditory neuropathy/dys-synchrony (AN/AD). To diagnose AN/AD accurately, ABRs are obtained in response to condensation and rarefaction clicks to distinguish cochlear microphonics (CM) from neural responses. Appropriate management is confounded by variation among patients and changes in auditory function in some patients over time. Recommendations for management include visual language exposure through methods such as American Sign Language (ASL), Cued Speech, or baby signs, and closely following patients. 相似文献
977.
Wilbrecht L Nottebohm F 《Mental retardation and developmental disabilities research reviews》2003,9(3):135-148
Vocal learning is the modification of vocal output by reference to auditory information. It allows for the imitation and improvisation of sounds that otherwise would not occur. The emergence of this skill may have been a primary step in the evolution of human language, but vocal learning is not unique to humans. It also occurs in songbirds, where its biology can be studied with greater ease. What follows is a review of some of the salient anatomical, developmental, and behavioral features of vocal learning, alongside parallels and differences between vocal learning in songbirds and humans. 相似文献
978.
A nonlinear mixed model framework for item response theory 总被引:1,自引:0,他引:1
Mixed models take the dependency between observations based on the same cluster into account by introducing 1 or more random effects. Common item response theory (IRT) models introduce latent person variables to model the dependence between responses of the same participant. Assuming a distribution for the latent variables, these IRT models are formally equivalent with nonlinear mixed models. It is shown how a variety of IRT models can be formulated as particular instances of nonlinear mixed models. The unifying framework offers the advantage that relations between different IRT models become explicit and that it is rather straightforward to see how existing IRT models can be adapted and extended. The approach is illustrated with a self-report study on anger. 相似文献
979.
Sources of individual differences in fraction skills 总被引:1,自引:0,他引:1
The purpose of this investigation was to evaluate a conceptual model of relations between two kinds of mathematical knowledge (simple arithmetic and conceptual knowledge), two kinds of child characteristics (working memory and on-task related classroom behavior), and individual differences in three kinds of fraction outcomes (fraction computation, estimation, and word problems) in 105 fifth grade students. Structural equation modeling provided consistent evidence that conceptual knowledge independently contributes to individual differences in the three fraction outcomes. Simple arithmetic knowledge was uniquely related only to variability in fraction computation skills. Mathematical knowledge was found to mediate some of the contributions of both working memory and classroom behavior on variability in fraction outcomes. These supported mediating processes extend the current literature by explication of the pathways via which characteristics of children may affect individual differences in fraction outcomes. 相似文献
980.
Is perseveration caused by inhibition failure? Evidence from preschool children's inferences about word meanings 总被引:2,自引:0,他引:2
Four studies examined the relation between children's cognitive inhibition and flexibility in a lexical inference task. Children's linguistic flexibility was assessed by the Flexible Induction of Meaning (FIM) test (Deák, 2000a), which requires that children shift inferences about the meanings of several words for novel objects. In Study 1, 54 3-year-olds either were trained between blocks of problems, for a delay of 3 min, or received no training or delay. Training delays did not influence perseveration. In Study 2 (N=72 3- and 4-year-olds') novel word problems were grouped either to increase the frequency of cue switches (i.e., reduce response "set") or minimize the interval between problems about the same objects. Again, no effect was found. In Study 3, 48 3- and 4-year-olds completed 6 preliminary trials; in a high interference group these trials generated a response set to be inhibited upon the first switch to a new cue context. This group did not perseverate more than a control group. There was no association between FIM perseveration and a Stroop-like test of verbal inhibition though both were marginally related to receptive vocabulary. In study 4 (48 3- and 4-year-olds), FIM was again unrelated to Stroop performance, but was related to the ability to tell whether a situation or problem is indeterminate. Thus, flexibility across semantic inferences is not influenced by timing, order, and number of pre-switch problems and is not predicted by individual differences in a test of verbal inhibition. However previously reported age and individual differences in flexible induction of word meanings are robust and related to vocabulary and logical ability. 相似文献