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701.
Cognitive enhancing substances such as amphetamine and modafinil have become popular in recent years to improve acute cognitive performance particularly in environments in which enhanced cognition or intelligence is required. Nutraceutical nootropics, which are natural substances that have the ability to bring about acute or chronic changes in cognition have also been gaining popularity in a range of settings and applications including the workplace, driving and in the amelioration of age related cognitive decline. Huperzine A, Vinpocetine, Acetyl-l-carnitine, Rhodiola Rosea and Alpha-lipoic Acid are popular nutritional supplements that have shown promising benefits in improving a range of biological (e.g., blood flow, anti-inflammatory, anti-oxidant, and direct neurotransmitter effects) and cognitive processes from in vitro, animal and human clinical research. We report here the first human randomized clinical trial for cognition in which we administer a combination of Huperzine A, Vinpocetine, Acetyl-l-carnitine, R. Rosea and Alpha-lipoic acid (called Ceretrophin) vs placebo. Sixty participants (40 females and 20 males, with a mean age of 45.4 years, SD = 12.6) completed either the odd or even items from the Raven Advanced Progressive Matrices (APM) at baseline and the opposite odd or even items at week 4 after consuming either the combination nootropic or placebo. A significant study visit (time) × treatment condition interaction was found: F (1, 57) = 7.279, p = 0.009, partial η2 = .113, with paired samples t-tests revealing a significant improvement in mean APM score from baseline to retest (week 4) (t(34) = ? 4.045, p < .001) for the Ceretrophin? group. Improvements in APM scores could be attributed to the active intervention over the placebo, indicating that the treatment improved general intelligence. Implications for improving our understanding of the biological basis of intelligence and pharmacologically improving human cognition are discussed.  相似文献   
702.
Research indicates that apoliprotein E (ApoE) plays a role in the development of Alzheimer's disease (AD) and possibly in the cognitive decline associated with normative aging. More recently, researchers have shown that ApoE is expressed in olfactory brain structures, and a relationship among ApoE, AD, and olfactory function has been proposed. In the current analyses, we investigated the contribution of ApoE and odor identification in decline trajectories associated with normative cognitive aging in various domains, using longitudinal data on cognitive performance available from the Swedish Adoption/Twin Study of Aging. Data on both ApoE status and olfactory functioning were available from 455 individuals ranging in age from 50 to 88 years at the first measurement occasion. Odor identification was measured via a mailed survey. Cognitive performance was assessed in up to 5 waves of in-person testing covering a period of 16 years. Latent growth curve analyses incorporating odor identification and ApoE status indicated a main effect of odor identification on the performance level in three cognitive domains: verbal, memory, and speed. A main effect of ApoE on rates of decline after age 65 was found for verbal, spatial, and speed factors. The consistency of results across cognitive domains provides support for theories that posit central nervous system-wide origins of the olfaction-cognition-ApoE relationship; however, olfactory errors and APOE ε4 show unique and differential effects on cognitive trajectory features.  相似文献   
703.
There are currently two computational accounts of how the time to read pseudohomophones (like BRANE) and their nonword controls (like FRANE) varies with changes in context. In Reynolds and Besner's (2005) account, readers vary the breadth of lexical activation in response to changes in context. A competing account proposed by Kwantes and Marmurek (2007) and independently by Perry, Ziegler, and Zorzi (2007) has readers varying their response criterion in response to changes in context. The present work adjudicates between these two accounts by examining how the effect of neighbourhood density changes as a function of list context when reading pseudohomophones aloud. The results of an experiment and simulations from a leading computational model support the lexical breadth account, but are inconsistent with the response criterion account.  相似文献   
704.
The belief in the gender invariance of many traits is a view that dominates much of psychology. In social psychology, this position is clearly represented by social dominance theory and the construct of social dominance orientation (SDO) where it is argued that, all else being equal, men will be higher in SDO than women. In other domains, though, these assumptions are being questioned, and researchers are arguing for a gender similarities hypothesis. The argument is that men and women are more similar than different, and where there are effects for gender, these are small. In this investigation, men and women are compared under similar cultural (Study 1), ideological, (Study 2) and status (Study 3) contexts to examine whether, all else being equal, men really are higher in SDO than women. In an additional study (Study 4), a meta‐analysis is conducted aggregating the effect sizes of the previous studies. Results demonstrated either no effect for gender or an interaction between gender and the relevant social context and only a small effect size of gender—findings that disconfirm the ceteris paribus assumption of social dominance theory. In conclusion, the implications of the findings for understanding gender effects in social psychology are discussed. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
705.
The goal of the current study was to examine environmental and genetic correlates of children’s levels of behavioral inhibition (BI). Participants were 100 mother child pairs drawn from the community who were part of a larger study of the intergenerational transmission of depression. Results indicated that higher levels of maternal overprotection, as reported by the child, were associated with elevations in BI among children carrying two copies of the lower expressing 5-HTTLPR alleles (S or LG), but not among those carrying only one copy or those homozygous for the LA allele. In addition, this interaction was specific for the social component of BI, not the nonsocial component. This relation was maintained even after statistically controlling for children’s and mother’s psychopathology. Together, these findings add to emerging research demonstrating that G × E interactions predict variation in BI during childhood.  相似文献   
706.
The World Wide Web (WWW) was 20 years old last year. Enormous amounts of information about stuttering are now available to anyone who can access the Internet. Compared to 20 years ago, people who stutter and their families can now make more informed choices about speech-language interventions, from a distance. Blogs and chat rooms provide opportunities for people who stutter to share their experiences from a distance and to support one another. New technologies are also being adopted into speech-language pathology practice and service delivery. Telehealth is an exciting development as it means that treatment can now be made available to many rural and remotely located people who previously did not have access to it. Possible future technological developments for speech-language pathology practice include Internet based treatments and the use of Virtual Reality. Having speech and CBT treatments for stuttering available on the Internet would greatly increase their accessibility. Second Life also has exciting possibilities for people who stutter.Educational objectives: The reader will (1) explain how people who stutter and their families can get information about stuttering from the World Wide Web, (2) discuss how new technologies have been applied in speech-language pathology practice, and (3) summarize the principles and practice of telehealth delivery of services for people who stutter and their families.  相似文献   
707.
This study was designed to investigate the partial assignment completion effect. Seventh-grade students were given a math assignment. After working for 5 min, they were interrupted and their partially completed assignments were collected. About 20 min later, students were given their partially completed assignment and a new, control assignment that contained the same number of equivalent problems that were incomplete on their partially completed assignment. Students were told that they would have to complete an assignment but could choose which assignment they completed. Significantly more students chose their partially completed assignment. Theoretical and applied implications and directions for future research are discussed.  相似文献   
708.
The term Direct-to-Consumer (DTC) genetic testing refers to many different categories of testing. This editorial addresses the issues related to DTC testing for large effect and small effect variants associated with disease. In particular, there are issues of clinical validity and utility, informativeness and residual risk. Genetic counselors are poised to address these issues because of their training in probability and statistical models. The authors suggest that genetic counselors can impact the general public’s understanding of DTC test results by: including evaluation of DTC concepts in graduate program curricula, holding AEC plenary sessions about emerging DTC concepts, and helping other professionals understand DTC concepts. Importantly, genetic counselors are advised to continue doing and promoting rigorous research on how people access and use DTC genetic testing and results, as well as gathering empirical data so that discussions of harms and benefits can go beyond theory. It is our hope that genetic counselors in practice will continue to critically evaluate claims made about emerging new tests, including those marketed DTC, in order to provide the best possible services to our patients.  相似文献   
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