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991.
Levy DL Bowman EA Abel L Krastoshevsky O Krause V Mendell NR 《Brain and cognition》2008,68(3):462-475
The “co-familiality” criterion for an endophenotype has two requirements: (1) clinically unaffected relatives as a group should show both a shift in mean performance and an increase in variance compared with controls; (2) performance scores should be heritable. Performance on the antisaccade task is one of several candidate endophenotypes for schizophrenia. In this paper we examine whether the various measures of performance on the standard version of the antisaccade task meet the co-familiality criterion for an endophenotype. The three measures of performance—reflexive saccade errors, latency of correct antisaccades, and gain—show a wide range of effect sizes and variance ratios as well as evidence of significant or near significant heterogeneity. The estimated mean effect sizes [Cohen’s d: error rate: 0.34 (SD: 0.29); latency: 0.33 (SD: 0.30); gain: 0.54 (SD: 0.38)] are significantly greater than 0, but the magnitude of the departures from 0 is relatively small, corresponding to modest effect sizes. The width of the 95% confidence intervals for the estimated effect sizes (error rate: 0.2–0.49; latency: 0.17–0.50; gain: 0.23–0.85) and the coefficients of variation in effect sizes (error rate: 85.3%; latency: 90.9%; gain: 68.4%) reflect heterogeneity in effect sizes. The effect sizes for error rate showed statistically significant heterogeneity and those for latency (P = .07) and gain (P = .09) showed a trend toward heterogeneity. These results indicate that the effect sizes are not consistent with a single mean and that the average effect size may be a biased estimate of the magnitude of differences in performance between relatives of schizophrenics and controls. Relatives of schizophrenics show a small but significant increase in variance in error rate, but the confidence interval is broad, perhaps reflecting the heterogeneity in effect size. The variance ratios for latency and gain did not differ in relatives of schizophrenics and controls. Performance, as measured by error rate, is moderately heritable. The data do not provide compelling support for a consistent shift in mean or variance in relatives of schizophrenia patients compared with nonpsychiatric controls, both of which are required for a major gene involved in co-familial transmission. This set of findings suggests that although intra-familial resemblance in antisaccade performance is due in part to genetic factors, it may not be related to a schizophrenia genotype. Based on the current literature, it would be premature to conclude that any of the measures of antisaccade performance unambiguously meets the co-familiality criterion for an endophenotype. 相似文献
992.
Storm BC Bjork EL Bjork RA 《Journal of experimental psychology. Learning, memory, and cognition》2008,34(1):230-236
Research on retrieval-induced forgetting has demonstrated that retrieving some information from memory can cause the forgetting of other information in memory. Here, the authors report research on the relearning of items that have been subjected to retrieval-induced forgetting. Participants studied a list of category- exemplar pairs, underwent a series of retrieval-practice and relearning trials, and, finally, were tested on the initially studied pairs. The final recall of non-relearned items exhibited a cumulative effect of retrieval-induced forgetting such that the size of the effect increased with each block of retrieval practice. Of most interest, and very surprising from a common-sense standpoint, items that were relearned benefited more from that relearning if they had previously been forgotten. The results offer insights into the nature and durability of retrieval-induced forgetting and provide additional evidence that forgetting is an enabler--rather than a disabler--of future learning. 相似文献
993.
Five experiments provide evidence for a primacy effect in the formation of inductive categories. Participants completed a category induction task in which they observed and reproduced a set of lines that varied in length but were serially ordered so that they increased or decreased in length. Subsequent estimates of the average of the distribution were systematically biased in the direction of stimuli encountered at the beginning of the induction task, suggesting that initially encountered stimuli exert greater weight in a category representation than do subsequent stimuli. We offer possible explanations for why this primacy effect might arise. 相似文献
994.
Beebe B Badalamenti A Jaffe J Feldstein S Marquette L Helbraun E Demetri-Friedman D Flaster C Goodman P Kaminer T Kaufman-Balamuth L Putterman J Stepakoff S Ellman L 《Journal of psycholinguistic research》2008,37(5):293-307
The prediction of events and the creation of expectancies about their time course is a crucial aspect of an infant's mental life, but temporal mechanisms underlying these predictions are obscure. Scalar timing, in which the ratio of mean durations to their standard deviations is held constant, enables a person to use an estimate of the mean for its standard deviation. It is one efficient mechanism that may facilitate predictability and the creation of expectancies in mother-infant interaction. We illustrate this mechanism with the dyadic gaze rhythm of mother and infant looking at and looking away from each other's faces. Two groups of Hi- and Lo-Distress mothers were created using self-reported depression, anxiety, self-criticism and childhood experiences. Lo-Distress infants (controls) used scalar timing 100% of the time, about double that of Hi-Distress infants. Lo-Distress mothers used scalar timing about nine times as much as Hi-Distress mothers. The diminished use of scalar timing patterns in Hi-Distress mothers and infants may make the anticipation of each other's gaze patterns more difficult for both partners. 相似文献
995.
To estimate the prevalence of being well-adjusted in adolescence, boys and girls with (n = 96) and without (n = 126) attention-deficit/hyperactivity disorder (ADHD) were assessed seven times in eight years starting when they were 4–6 years
of age. Symptoms of ADHD, ODD/CD, and depression/anxiety in addition to social skills and social preference were gathered
using multiple methods and informants. Being well-adjusted was defined by surpassing thresholds in at least four of the five
domains. At the 7- and 8-year follow-up, when youth were 11–14 years old, probands were significantly less likely to be well-adjusted
relative to age- and ethnicity-matched control children. Only a minority of children with ADHD was well-adjusted in adolescence
when emotional, behavioral, and social domains were considered simultaneously. Even when their ADHD symptoms improved over
time, most probands exhibited significant impairment 7–8 years after their initial assessment. 相似文献
996.
Drawing on transactional theories of child development, we assessed bidirectional links between trajectories of adolescent
substance use and parenting processes from early through mid adolescence. Hierarchical generalized models estimated trajectories
for 3,317 adolescents from the National Longitudinal Survey of Youth 1997, exploring both between- and within-individual effects.
Between individuals, adolescents reporting more regular family activities and greater father and mother knowledge of friends
and teachers experienced lower levels of substance use through mid adolescence. Similarly, adolescents with more frequent
substance use reported lower family activities, father knowledge, and mother knowledge, though these differences dissipated
over time. More conservative within-individual differences indicated a prospective protective effect of family activities,
with increases in adolescent participation in family activities predicting later declines in substance use. Results support
the central importance of engagement in regular family activities, and suggest the need for further exploration of transactional
processes between parents and children in the development of risk behaviors. 相似文献
997.
Response Style Differences in the Inattentive and Combined Subtypes of Attention-Deficit/Hyperactivity Disorder 总被引:1,自引:0,他引:1
Derefinko KJ Adams ZW Milich R Fillmore MT Lorch EP Lynam DR 《Journal of abnormal child psychology》2008,36(5):745-758
This study examined potential differences between the inattentive and combined ADHD subtypes using laboratory tasks assessing behavioral inhibitory processes. Seventy-five children completed two tasks of behavioral inhibition believed to isolate different processes: the cued reaction time task (CRT), a basic inhibition task, and the go/no-go task (GNG), a complex inhibition task that incorporates motivational contingencies. Three groups of participants were identified, including ADHD/Inattentive (n = 17), ADHD/Combined (n = 37), and comparison (n = 21). Results indicated that rather than showing behavioral inhibition deficits, the ADHD/I children appeared overly inhibited, as evidenced by slower reaction times across the two tasks and significantly higher errors of omission in the GNG task. Additionally, the ADHD/I children did not demonstrate cue dependency effects on the CRT task, suggesting that they were failing to incorporate relevant information before making a response. The sluggish and inhibited performance of the ADHD/I group challenges the idea that it is a subtype of ADHD. 相似文献
998.
Overconcern with weight and shape and body dissatisfaction have both emerged as significant predictors of disordered eating. However, it is unclear how these constructs relate to each other, and if each has different antecedents and consequences. This study aimed to identify prospective predictors of each construct and to determine their relative importance in predicting dietary restraint and binge eating. Eight- to 13-year-old boys and girls (N = 259) were assessed at baseline and one-year follow-up, using a range of measures that included the Child Eating Disorder Examination. Psychosocial variables predicted overconcern with weight and shape whilst objective weight predicted body dissatisfaction. Body dissatisfaction and weight and shape concern predicted restraint, and weight and shape concern and restraint predicted binge eating. Findings provide support for the theoretical differences between body dissatisfaction and overconcern with weight and shape, and highlight the importance of focusing on specific body image variables. 相似文献
999.
The current study was conducted to determine if electronic gaming among males is related to body image, formation of body ideals, and appraisals of female attractiveness. A sample of 219 college-aged men (age 18-32) completed a variety of measures that assessed their game play habits, their perceptions of their own attractiveness, and perceptions of women's attractiveness. Results indicated that participants' ratings of women's attractiveness varied across the genres of game most frequently played but was not related to age of commencement or frequency of electronic game play. Additionally, frequency of play and age of commencement of game play were not related to self-perceptions of physical attractiveness, the association of positive attributes with muscularity, or the drive to become more muscular. Men's appearance satisfaction and valuation of muscularity was related to the extent to which they compare their own appearance to that of the characters featured in their electronic games. The results indicate that, unlike other forms of media, electronic gaming may have a weaker relationship to decreased appearance satisfaction or the formation of unrealistic standards of attractiveness. 相似文献
1000.
Prior research has examined the relations between various facets of emotion and psychopathology, with a great deal of recent work highlighting the importance of emotion regulation strategies. Much less attention has been given to the examination of emotion reactivity. This study reports on the development and evaluation of the Emotion Reactivity Scale (ERS), a 21-item self-report measure of emotion sensitivity, intensity, and persistence, among a sample of 87 adolescents and young adults. Factor analysis revealed a single factor of emotion reactivity best characterized the data. The ERS showed strong internal consistency (alpha=.94), convergent and divergent validity via relations with behavioral inhibition/activation and temperament, and criterion-related validity as measured by associations with specific types of psychopathology and self-injurious thoughts and behaviors (SITB). Moreover, emotion reactivity statistically mediated the relation between psychopathology and SITB. These findings provide preliminary support for the ERS and suggest that increased emotion reactivity may help explain the association between psychopathology and SITB. 相似文献