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801.
In older adults, difficulties processing complex auditory scenes, such as speech comprehension in noisy environments, might be due to a specific impairment of temporal processing at early, automatic processing stages involving auditory sensory memory (ASM). Even though age effects on auditory temporal processing have been well-documented, there is a paucity of research on how ASM processing of more complex tone-patterns is altered by age. In the current study, age effects on ASM processing of temporal and frequency aspects of two-tone patterns were investigated using a passive listening protocol. The P1 component, the mismatch negativity (MMN) and the P3a component of event-related brain potentials (ERPs) to tone frequency and temporal pattern deviants were recorded in younger and older adults as a measure of auditory event detection, ASM processing, and attention switching, respectively. MMN was elicited with smaller amplitude to both frequency and temporal deviants in older adults. Furthermore, P3a was elicited only in the younger adults. In conclusion, the smaller MMN amplitude indicates that automatic processing of both frequency and temporal aspects of two-tone patterns is impaired in older adults. The failure to initiate an attention switch, suggested by the absence of P3a, indicates that impaired ASM processing of patterns may lead to less distractibility in older adults. Our results suggest age-related changes in ASM processing of patterns that cannot be explained by an inhibitory deficit.  相似文献   
802.
The present study examines two varieties of working memory (WM) capacity task: visual arrays (i.e., a measure of the amount of information that can be maintained in working memory) and complex span (i.e., a task that taps WM-related attentional control). Using previously collected data sets we employ confirmatory factor analysis to demonstrate that visual arrays and complex span tasks load on separate, but correlated, factors. A subsequent series of structural equation models and regression analyses demonstrate that these factors contribute both common and unique variance to the prediction of general fluid intelligence (Gf). However, while visual arrays does contribute uniquely to higher cognition, its overall correlation to Gf is largely mediated by variance associated with the complex span factor. Thus we argue that visual arrays performance is not strictly driven by a limited-capacity storage system (e.g., the focus of attention; Cowan, 2001), but may also rely on control processes such as selective attention and controlled memory search.  相似文献   
803.
The influence of semantic relationships on older adult map memory   总被引:1,自引:0,他引:1  
Research has shown that nonspatial features, including semantic categories, can bias younger adults' spatial location memory. For example, semantically related information is remembered as being closer in space than semantically unrelated information (Hirtle & Mascolo, 1986). These findings suggest that verbal information is concurrently encoded with spatial information and influences younger adults' spatial information retrieval. The present study explored whether older adults have a similar dependency between verbal and spatial information. In Experiment 1, older and younger adults learned maps depicting semantically categorizable landmarks. After learning, participants completed landmark free recall and distance estimation tasks. Younger adults recalled more landmarks from semantically organized maps compared with older adults. In addition, younger adults were more likely to underestimate the distance between semantically related landmarks than were older adults. Experiment 2 examined whether supportive instructions would influence older adults' use of verbal information when learning maps. When given instructions that encouraged semantic feature use, older adults remembered more landmarks, were more likely to cluster landmarks semantically, and demonstrated biases in distance estimation based on semantic relationships. These findings suggest that verbal influences on spatial/map learning in older adults depends on explicit instructions or environmental support at encoding. (PsycINFO Database Record (c) 2012 APA, all rights reserved).  相似文献   
804.
The roles of previous psychological service use and social network variables in beliefs about psychological services were examined with 184 college students. Having friends and family members who used psychological services, being female, and having used psychological services positively related with beliefs about psychological services. Socioracial differences in the effects of previous use of psychological services and social network variables on students’ beliefs about psychological services were found. Suggestions for ways counselors can provide support to students are discussed.  相似文献   
805.
The current study examined whether the Avoidance and Fusion Questionnaire for Youth (AFQ-Y; L. A. Greco, W. Lambert, & R. A. Baer, 2008), a self-report measure of psychological inflexibility for children and adolescents, might be useful for measuring psychological inflexibility for adults. The psychometric properties of the AFQ-Y were examined using data from a college student sample (N = 387) and a clinical sample of patients with anxiety disorders (N = 115). The AFQ-Y, but not the Acceptance and Action Questionnaire-II (AAQ-II; F. W. Bond et al., in press), demonstrated a reading level at or below the recommended 5th or 6th grade reading level. The AFQ-Y also demonstrated adequate reliability (internal consistency), factorial validity, convergent and discriminant validity, and concurrent validity predicting psychological symptoms. Moreover, the AFQ-Y showed incremental validity over the AAQ-II in predicting several psychological symptom domains. Implications for the assessment of psychological inflexibility are discussed.  相似文献   
806.
Hungry animals will often choose suboptimally by being attracted to reliable signals for food that occur infrequently (they gamble) over less reliable signals for food that occur more often. That is, pigeons prefer an option that 50?% of the time provides them with a reliable signal for the appearance of food but 50?% of the time provides them with a reliable signal for the absence of food (overall 50?% reinforcement) over an alternative that always provides them with a signal for the appearance of food 75?% of the time (overall 75?% reinforcement). The pigeons appear to choose impulsively for the possibility of obtaining the reliable signal for reinforcement. There is evidence that greater hunger is associated with greater impulsivity. We tested the hypothesis that if the pigeons were less hungry, they would be less impulsive and, thus, would choose more optimally (i.e., on the basis of the overall probability of reinforcement). We found that hungry pigeons choose the 50?% reinforcement alternative suboptimally but less hungry pigeons prefer the more optimal 75?% reinforcement. Paradoxically, pigeons that needed the food more received less of it. These findings have implications for how level of motivation may also affect human suboptimal choice (e.g., purchase of lottery tickets and playing slot machines).  相似文献   
807.
The loss of a client to suicide is a painful personal and professional experience for mental health providers. Whether trainee or experienced professional, the affected clinician often reports feeling overwhelmed and unprepared for the experience of client suicide, together with significant emotional distress and diminished work performance. In this article, we present a brief overview of the literature on the impact of client suicide and ideas for coping with the psychological and professional issues that typically arise. We also provide suggestions for managing the associated practical and administrative tasks, as well as resources for obtaining professional support and guidance in the wake of this tragic event.  相似文献   
808.
Objective: Preclinical models, receptor localization, and genetic linkage data support the role of D4 receptors in the etiology of ADHD. This proof-of-concept study was designed to evaluate MK-0929, a selective D4 receptor antagonist as treatment for adult ADHD. Method: A randomized, double-blind, placebo-controlled, crossover study was conducted in adults with primary ADHD. The primary end point was changed from baseline in total score on the Adult ADHD Investigator Symptom Rating Scale following a 4-week treatment regimen. Additional measures included Clinical Global Impression-Severity Scale, Hospital Anxiety and Depression Scale, and Brown Attention Deficit Disorder Scale and D4 genotype analysis. Results: No statistically significant treatment differences were found between MK-0929 and placebo in any of the primary or secondary assessments. Conclusion: Results from this study suggest that blockade of the D4 receptor alone is not efficacious in the treatment of adult ADHD.  相似文献   
809.
Advances in technology now make it possible to monitor the activity of the human brain in action, however crudely. As this emerging science continues to offer correlations between neural activity and mental functions, mind and brain may eventually prove to be one. If so, such a full comprehension of the electrochemical bases of mind may render current concepts of ethics, law, and even free will irrelevant.  相似文献   
810.
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