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151.
Genetic and environmental influences in social attitudes were investigated in adopted and nonadopted children (N = 654) and their biological and adoptive relatives in the Colorado Adoption Project. Conservatism and religious attitudes were measured in the children annually from ages 12 to 15 and in the parents during the 12-year-old visit. Multivariate genetic model fitting indicated that both conservatism and religious attitudes are strongly influenced by shared-family environmental factors throughout adolescence. In contrast to previous findings from twin studies, which suggest that genetic influence on social attitudes does not emerge until adulthood, the present study detected significant genetic influence in conservatism as early as age 12. There was no evidence of genetic influence, however, on religious attitudes during adolescence. 相似文献
152.
The effect of pyridoxine (Vitamin B-6) on dreaming was investigated in a placebo, double-blind study to examine various claims that Vitamin B-6 increases dream vividness or the ability to recall dreams. 12 college students participated in all three treatment conditions, each of which involved ingesting either 100 mg B-6, 250 mg B-6, or a placebo prior to bedtime for a period of five consecutive days. The treatment conditions were completely counterbalanced and a two-day wash-out period occurred between the three five-day treatment blocks. Morning self-reports indicated a significant difference in dream-salience scores (this is a composite score containing measures on vividness, bizarreness, emotionality, and color) between the 250-mg condition and placebo over the first three days of each treatment. The data for dream salience suggests that Vitamin B-6 may act by increasing cortical arousal during periods of rapid eve movement (REM) sleep. An hypothesis is presented involving the role of B-6 in the conversion of tryptophan to serotonin. However, this first study needs to be replicated using the same procedures and also demonstrated in a sleep laboratory before the results can be considered certain. 相似文献
153.
The role of neighborhood factors in predicting hopelessness among adolescent suicide attempters was examined in this study. Forty-eight adolescents who attempted suicide were administered measures of hopelessness and depression. Family socioeconomic status (SES) was calculated based on family demographics and characteristics of neighborhood context were examined using a geocoding software package. Adolescents who lived in neighborhoods with weak social networks reported higher levels of hopelessness, even after controlling for SES and depression. These preliminary findings suggest that environmental context may play a role in the emotional status of adolescents who attempt suicide. 相似文献
154.
Hofer SM Christensen H Mackinnon AJ Korten AE Jorm AF Henderson AS Easteal S 《Psychology and aging》2002,17(2):194-208
The influence of a genetic risk factor, apolipoprotein E (apoE) epsilon4 variant, was assessed in older adults aged 70 to 94 on 3 occasions over 7 years. The results of latent growth curve analyses are reported for individuals genotyped for apoE at the 2nd measurement occasion (n = 601) and for a subsample of individuals without probable or definite dementia during the 1st or 2nd occasion (n = 434). ApoE-epsilon4 status was a significant predictor of level and change in memory performance and change in speed performance in the full sample, and of initial level and change in memory performance in the nondemented subsample. These results support previous findings that apoE-epsilon4 is associated with accelerated memory deterioration in individuals without clinical dementia. 相似文献
155.
Hempel AG Kownacki R Malin DH Ozone SJ Cormack TS Sandoval BG Leinbach AE 《Behavioral sciences & the law》2002,20(5):507-522
An archival study was performed in a maximum security forensic hospital to evaluate the effects of a total ban on smoking and all tobacco products. One hundred and forty patients were characterized as nonsmokers or light, moderate or heavy smokers. Patient records for the four weeks prior to the ban were compared with their records for the four weeks subsequent to the ban. Numbers of sick calls, total disruptive behaviors and verbal aggression declined markedly and significantly following the ban in those patients previously classified as moderate or heavy smokers. Weight increased significantly, but almost equally regardless of previous smoking status. Patients, and eventually staff, tolerated the smoking ban without significant negative effects. Patients relied very little on treatment modalities to alleviate nicotine withdrawal. Pre-ban apprehension by staff and patients dissipated with time after the smoking ban started. 相似文献
156.
157.
Laura Bishop 《Theoretical medicine and bioethics》2002,23(6):545-546
Other Index
Index to Volume 23 相似文献158.
Laura?Barca Cristina?BuraniEmail author Lisa?S.?Arduino 《Behavior research methods》2002,34(3):424-434
The present study describes normative measures for 626 Italian simple nouns. The database (LEXVAR. XLS) is freely available for down-loading on the Web site http://wwwistc.ip.rm.cnr.it/material/ database/. For each of the 626 nouns, values for the following variables are reported: age of acquisition, familiarity, imageability, concreteness, adult written frequency, child written frequency, adult spoken frequency, number of orthographic neighbors, mean bigram frequency, length in syllables, and length in letters. A classification of lexical stress and of the type of word-initial phoneme is also provided. The intercorrelations among the variables, a factor analysis, and the effects of variables and of the extracted factors on word naming are reported. Naming latencies were affected primarily by a factor including word length and neighborhood size and by a word frequency factor. Neither a semantic factor including imageability, concreteness, and age of acquisition nor a factor defined by mean bigram frequency had significant effects on pronunciation times. These results hold for a language with shallow orthography, like Italian, for which lexical nonsemantic properties have been shown to affect reading aloud. These norms are useful in a variety of research areas involving the manipulation and control of stimulus attributes. 相似文献
159.
This study examines the prevalence, stability, and contextual correlates of peer victimization in a sample of African-American, Hispanic, and non-Hispanic White urban elementary school-age children. A total of 1956 children (40% African-American, 42% Hispanic, and 18% White) attending any 1 of 14 public elementary schools located in one large and one mid-sized Midwestern city participated in this study. Peer ratings of victimization were obtained at two points in time, separated by a 2-year period. Findings revealed that risk for being victimized by peers varied by ethnicity and by school context. Hispanic children had lower victimization scores than did either African-American or White children. These findings, however, were moderated by school context, such that attending ethnically integrated schools was associated with a significantly higher risk of victimization for White children and a slightly lower risk of victimization for African-American children and did not affect the risk of victimization for Hispanic children. In addition, African-American children were less likely than Hispanic and White children to be repeatedly victimized by peers over time. The importance of considering ethnicity and context in explaining peer victimization is discussed and suggestions for preventive interventions and future research are provided. 相似文献
160.
Implicit motor sequence learning is represented in response locations 总被引:17,自引:0,他引:17
Previous work (Willingham, 1999) has indicated that implicit motor sequence learning is not primarily perceptual; that is, what is learned is not a sequence of stimuli. Still other work has indicated that implicit motor sequence learning is not specific to particular muscle groups or effectors. In the present work, we tested whether implicit motor sequence learning would be represented as a sequence of response locations. In Experiment 1, learning showed very poor transfer when the response locations were changed, even though the stimulus positions were unchanged. In Experiment 2, participants switched their hand positions at transfer, so that one group of participants pushed the same sequence of keys but used a different sequence of finger movements to do so, whereas another group pushed a different sequence of keys but used the same sequence of finger movements used at training. Knowledge of the sequence was shown at transfer only if the sequence of response locations was maintained, not the sequence of finger movements. 相似文献