Universal sex differences in the desire for sexual variety: tests from 52 nations, 6 continents,and 13 islands

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.     

Lateralized effects of subthalamic nucleus stimulation on different aspects of speech in Parkinson's disease

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.     

The Revised Memory and Behavior Problems Checklist--Nursing Home: instrument development and measurement of burden among certified nursing assistants

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.     

Combined uridine and choline administration improves cognitive deficits in spontaneously hypertensive rats

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.     

A nonlinear mixed model framework for item response theory

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.     

Is perseveration caused by inhibition failure? Evidence from preschool children's inferences about word meanings

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.     

Present mood states in Brazilian night nurses

Variations in the state of momentary emotions of Brazilian hospital nurses on day and night shifts were recorded. Ten graduate nurses working on day and night shifts in the clinical ward of hospitals completed the Present Mood States List of Engelmann at the beginning and end of the first and last days of each shift. Analysis indicated (a) nurses had a stable emotional profile, present at the working shift, and (b) variations in present mood states related to specific effects of shift work were observed when comparisons were made between the present mood states at the beginning and end of each shift duty.     

Estimation of the MIRID: A program and a SAS-based approach

The MIRID CML program is a program for the estimation of the parameter values of two different componential IRT models: the Rasch—MIRID and the OPLM—MIRID (Butter, 1994; Butter, De Boeck, & Verhelst, 1998). To estimate the parameters of both models, the program uses a CML approach. The model parameters can also be estimated with a MML approach that can be implemented in PROC NLMIXED of SAS Version 8. Both the MIRID CML program and the MML SAS approach are explained and compared in a simulation study. The results showed that they did about equally well in estimating the values of the item parameters but that there were some differences in the estimation of the person parameters, as could be expected from the differential assumptions regarding the distribution of the persons. The SAS MML approach is much slower than the MIRID CML program, but it is more flexible.     

Acculturation and Cognitive Performance of Migrant Children in The Netherlands

Acculturative strategies and cognitive acculturation were studied among 118 Dutch migrant children (age: 7–12 years). Both an exploratory factor analysis and a Linear Logistic Test Model analysis provided evidence for the bipolar unidimensionality of Berry's four acculturation strategies; integration constituted one pole and assimilation, separation, and marginalization the other. Integration was by far the most popular strategy. Cognitive performance was measured by the Snijders-Oomen Nonverbal Intelligence Test, school report measures, and a computer-assisted choice reaction-time measure. A good fit was found for a structural model that postulated cognitive acculturation as the latent variable linking background measures (i.e. acculturation strategy, second language usage, age, and gender) to the cognitive measures. Relationships between background variables and cognitive performance were stronger in the first than in the second generation. Both older children and children who favour an integration strategy showed a higher degree of cognitive acculturation.     

Gay Identity and the Experience of Gay Social Stress1

The hypothesis that identity commitment affects the experience of identity-related stressors brings identity theory and social stress research together. Research findings are not yet conclusive regarding this hypothesis. Part of the contradictory research findings stem from inadequate knowledge about the causal direction of the relationship between depression and commitment. The authors analyze if identity commitment interacts with social stress in its impact on mental well-being. Only chronic stress has a moderate impact on the experience of depression. Commitment toward the gay identity did not buffer the experience of stress. The authors also use a nonrecursive model to establish the causal relationship between depression and commitment. They show that it is depression that lowers identity commitment. It is concluded that identity commitment cannot act as a buffer against identity-related stress because commitment is affected by the resulting distress.