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161.
Tooth whitening has become a very popular procedure. Advertisements for whitening products imply that whiter teeth are more attractive than yellower teeth. We tested this idea empirically by manipulating the tooth color of pictures of male and female targets. Participants' ratings of attractiveness were not influenced by tooth color. Exp. 2 yielded a negative correlation between attractiveness and age ratings: targets judged to be older were rated as less attractive. Unless whiter teeth help in some other way, e.g., improved self-esteem or confidence, it seems that tooth whitening procedures or products are not associated with increased attractiveness to others.  相似文献   
162.
When disoriented in a closed rectangular tank, fish (Xenotoca eiseni) reoriented in accord with the large-scale shape of the environment, but they were also able to conjoin geometric information with nongeometric properties such as the color of a wall or the features provided by panels located at the corners of the tank. Fish encoded geometric information even when featural information sufficed to solve the spatial task. When tested after transformations that altered the original arrangement of the panels, fish were more affected by those transformations that modified the geometric relationship between the target and the shape of the environment. Finally, fish appeared unable to use nongeometric information provided by distant panels. These findings show that a reorientation mechanism based on geometry is widespread among vertebrates, though the joint use of geometric and nongeometric cues by fish suggest that the degree of information encapsulation of the mechanism varies considerably between species.  相似文献   
163.
To investigate the prevalence of thought disorder and the possible appropriateness of the Bizarre-Idiosyncratic Thinking Scale for children and adolescents with severe psychiatric disorders, 96 child and adolescent inpatients and day hospital patients, ages 6 to 18 years, at a state psychiatric hospital were rated by review of retrospective records using Marengo and Harrow's 1986 Evaluation of Bizarre-Idiosyncratic Thinking Scale for the presence of thought disorder in the Thematic Apperception Test and Rorschach Inkblot Test responses. Although the Evaluation of Bizarre-Idiosyncratic Thinking Scale had not been previously used with children and adolescents, the analysis suggested possible indications of thought disorder in several diagnostic groups. No significant differences were found on the Rorschach between patients with Schizophrenia and Psychosis, Not Otherwise Specified and those with Attention Deficit Hyperactivity Disorder, Major Depression, and Conduct Disorder. On the basis of the Thinking Scale ratings, the Thematic Apperception Test responses showed significantly higher ratings of thought disorder for patients with Schizophrenia and Psychosis, Not Otherwise Specified. There was no general relation between thought disorder and age or IQ, but schizophrenic patients, aged 13 and older, had more thought disorder than schizophrenic patients who were younger than 13.  相似文献   
164.
This study evaluates a measurement model for Attention Deficit/Hyperactivity Disorder (ADHD). The DSM-IV divides 18 symptoms into two groups, inattentive and hyperactive/impulsive. Elementary school teachers rated 21,161 children in 4 locations: Spain, Germany, urban US, and suburban US. Confirmatory factor analysis suggested that the 2-factor model (inattention, hyperactivity/impulsivity) shows the best fit. A third factor, impulsivity, was too slight to stand-alone. Children with academic performance problems were distinguished by inattention, but children with behavior problems typically had elevations in inattention, hyperactivity, and impulsivity. Between-site differences were statistically significant, but so small that we conclude that same measurement model fits all 4 samples in 2 continents.  相似文献   
165.
Serial expertise of rhesus macaques   总被引:5,自引:0,他引:5  
Here we describe the development of serial expertise in 4 experimentally naive rhesus monkeys that learned, by trial and error, the correct order in which to respond to 3-, 4-, and 7-item lists of arbitrarily selected photographs. The probabilities of guessing the correct sequence on 3-, 4-, and 7-item lists were, respectively, 1/6, 1/24, and 1/5040. Each monkey became progressively more efficient at determining the correct order in which to respond on new lists. During subsequent testing, the subjects were presented with all possible pairs of the 28 items used to construct the four 7-item lists (excluding pairs of items that occupied the same ordinal position in different lists). Subjects responded to pairs from different lists in the correct order 91% of the time on the first trials on which these pairs were presented. These features of subjects' performance, which cannot be attributed to procedural memory, satisfy two criteria of declarative memory: rapid acquisition of new knowledge and flexible application of existing knowledge to a new problem.  相似文献   
166.
The authors examined the level and structure of the Inventory of Interpersonal Problems-Circumplex version (IIP-C; L. M. Horowitz, L. E. Alden, J. S. Wiggins, & A. L. Pincus, 2000) before and after 20 sessions of acute-phase cognitive therapy for depression (N = 118), as well as associations with the Schedule for Nonadaptive and Adaptive Personality (L. A. Clark, 1993b) and the Social Adjustment Scale--Self-Report version (M. M. Weissman & S. Bothwell, 1976). Interpersonal problems had a 3-factor structure (Interpersonal Distress, Love, and Dominance), with the latter 2 factors approximating a circumplex, both before and after therapy. Interpersonal Distress decreased and social adjustment increased with therapy, but the Love and Dominance dimensions were relatively stable, similar to personality constructs. Social adjustment related negatively to Interpersonal Distress but not to Love or Dominance. Personality pathology related broadly to Interpersonal Distress and discriminantly to Love and Dominance. These findings support the reliability and validity of the IIP-C and are discussed in the context of personality theory and measurement.  相似文献   
167.
A theory of diversity in speeded cognition, the difference engine, is proposed, in which information processing is represented as a series of generic computational steps. Some individuals tend to perform all of these computations relatively quickly and other individuals tend to perform them all relatively slowly, reflecting the existence of a general cognitive speed factor, but the time required for response selection and execution is assumed to be independent of cognitive speed. The difference engine correctly predicts the positively accelerated form of the relation between diversity of performance, as measured by the standard deviation for the group, and task difficulty, as indexed by the mean response time (RT) for the group. In addition, the difference engine correctly predicts approximately linear relations between the RTs of any individual and average performance for the group, with the regression lines for fast individuals having slopes less than 1.0 (and positive intercepts) and the regression lines for slow individuals having slopes greater than 1.0 (and negative intercepts). Similar predictions are made for comparisons of slow, average, and fast subgroups, regardless of whether those subgroups are formed on the basis of differences in ability, age, or health status. These predictions are consistent with evidence from studies of healthy young and older adults as well as from studies of depressed and age-matched control groups.  相似文献   
168.
A rodent model of diencephalic amnesia, pyrithiamine-induced thiamine deficiency (PTD), was used to investigate diencephalic-hippocampal interactions. Acetylcholine (ACh) release, a marker of memory-related activation, was measured in the hippocampus of PTD-treated and control rats prior to, during, and after spontaneous alternation test. During behavioral testing, all animals displayed increases in ACh release. However, both the percent increase of ACh release during spontaneous alternation testing and the alternation scores were higher in control rats relative to PTD-treated rats. Thus, when rats are tested on a task with demands dependent on the hippocampus, it appears that the hippocampus is not fully activated after diencephalic damage.  相似文献   
169.
Emerging as one of the most significant health issues facing American youth today, child and adolescent exposure to community violence has generated much interest across multiple disciplines. Most research to date has focused on documenting the prevalence of community violence and the emotional and behavioral ramifications. This paper provides an overview of the current literature regarding prevalence of youth exposure to community violence, and identifies those areas where further research is warranted. In addition to examining overall rates of community violence exposure, this paper reviews the prevalence of different types of community violence, such as weapon use, physical aggression, and crime-related events. Predictors of community violence exposure, including gender, age, race, socioeconomic status, behavior patterns, and geography, are discussed.  相似文献   
170.
Self-conscious emotions such as embarrassment and shame are associated with 2 aspects of theory of mind (ToM): (a) the ability to understand that behavior has social consequences in the eyes of others and (b) an understanding of social norms violations. The present study aimed to link ToM with the recognition of self-conscious emotion. Children with and without autism identified facial expressions conscious of self-conscious and non-self-conscious emotions from photographs. ToM was also measured. Children with autism performed more poorly than comparison children at identifying self-conscious emotions, though they did not differ in the recognition of non-self-conscious emotions. When ToM ability was statistically controlled, group differences in the recognition of self-conscious emotion disappeared. Discussion focused on the links between ToM and self-conscious emotion.  相似文献   
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