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821.
Moscoso del Prado Martín F Bertram R Häikiö T Schreuder R Baayen RH 《Journal of experimental psychology. Learning, memory, and cognition》2004,30(6):1271-1278
Finnish has a very productive morphology in which a stem can give rise to several thousand words. This study presents a visual lexical decision experiment addressing the processing consequences of the huge productivity of Finnish morphology. The authors observed that in Finnish words with larger morphological families elicited shorter response latencies. However, in contrast to Dutch and Hebrew, it is not the complete morphological family of a complex Finnish word that codetermines response latencies but only the subset of words directly derived from the complex word itself. Comparisons with parallel experiments using translation equivalents in Dutch and Hebrew showed substantial cross-language predictivity of family size between Finnish and Dutch but not between Finnish and Hebrew, reflecting the different ways in which the Hebrew and Finnish morphological systems contribute to the semantic organization of concepts in the mental lexicon. 相似文献
822.
Event-related potential (ERP) studies have demonstrated impaired auditory sensory processing in patients with schizophrenia, as reflected in abnormal mismatch negativity (MMN). We sought to extend this finding by evaluating MMN in 13 treatment-refractory patients with schizophrenia, and 14 age- and gender-matched healthy controls. Subjects responded to infrequent visual stimulation while ignoring binaurally presented auditory tones. The amplitude and topographical pattern of the MMN were analyzed. The control group presented the expected reduction in the amplitude of the MMN from frontal to central and parietal locations. In comparison, the MMN amplitude was not reduced in the treatment-refractory patients, and was largest at the central-posterior electrode location. In addition, patients displayed larger negativities at left frontal, and left- and right-temporal electrode locations than the control subjects. These findings are consistent with pre-attentive abnormalities in treatment-refractory patients with schizophrenia. 相似文献
823.
Robert?G.?CookEmail author Alfred?I.?Geller Guo-Rong?Zhang Ram?Gowda 《Behavior research methods》2004,36(1):101-106
The efficiency of traditional levers and of modern touchscreen technology for training rats on a computerized visual discrimination
was studied in a series of observations. When compared with a lever-based discrimination procedure, the use of touchscreens
supported the faster development of signal tracking behavior and acquisition of a two-stimulus simultaneous visual discrimination.
It did not affect the final level of accuracy. Factors related to spatial proximity of the responses with the stimuli, sign-tracking,
and increased ease of touchscreen motor responses were suggested as possible reasons for the touchscreen training advantage.
This increased efficiency allows large numbers of animals to be tested quickly, a necessary requirement for studies involving
genetic and physiological interventions. 相似文献
824.
The purpose of this study was to determine how 391 Caucasian American mothers of 10- to 14-year-olds viewed their assets and limitations as parents and to find out how 352 adolescents perceived the parenting performance of their mothers. Both generations completed the Parent Success Indicator. It was found that the amount of time mothers spent talking to, and doing things with, their adolescent children had the greatest impact on how both generations rated mother success. 相似文献
825.
The visual working memory (WM) storage capacity of patients with schizophrenia was investigated using a change detection paradigm. Participants were presented with 2, 3, 4, or 6 colored bars with testing of both single feature (color, orientation) and feature conjunction conditions. Patients performed significantly worse than controls at all set sizes but demonstrated normal feature binding. Unlike controls, patient WM capacity declined at set size 6 relative to set size 4. Impairments with subcapacity arrays suggest a deficit in task set maintenance: Greater impairment for supercapacity set sizes suggests a deficit in the ability to selectively encode information for WM storage. Thus, the WM impairment in schizophrenia appears to be a consequence of attentional deficits rather than a reduction in storage capacity. 相似文献
826.
Delayed matching to complex, two-picture samples (e.g., cat-dog) may be improved when the samples occasion differential verbal behavior. In Experiment 1, individuals with mental retardation matched picture comparisons to identical single-picture samples or to two-picture samples, one of which was identical to a comparison. Accuracy scores were typically high on single-picture trials under both simultaneous and delayed matching conditions. Scores on two-picture trials were also high during the simultaneous condition but were lower during the delay condition. However, scores improved on delayed two-picture trials when each of the sample pictures was named aloud before comparison responding. Experiment 2 replicated these results with preschoolers with typical development and a youth with mental retardation. Sample naming also improved the preschoolers' matching when the samples were pairs of spoken names and the correct comparison picture matched one of the names. Collectively, the participants could produce the verbal behavior that might have improved performance, but typically did not do so unless the procedure required it. The success of the naming intervention recommends it for improving the observing and remembering of multiple elements of complex instructional stimuli. 相似文献
827.
In this research, we examined the convergent validity, internal structure, and interparent agreement of the Child Behavior Checklist (CBCL; Achenbach, 1991a) using data from a community sample of 317 high-risk families. The sample consisted of 218 families with alcoholism (biological mother, father, and son) and 99 matched comparison families without alcoholism; all families were intact and included a 3- to 5-year-old son at first contact. Evidence was found for the convergent validity of the CBCL. In addition, although interparent agreement was low, the internal structure was confirmed, and structural invariance was high between mothers and fathers and in families with and without alcoholism. The effects of parental psychological and cognitive functioning on parent agreement were examined and found to have a minimal effect on parent agreement. These results demonstrate the validity of the CBCL for use by parent raters with alcoholism and their sons and emphasize the importance of including both versus only 1 parent in research using the CBCL. 相似文献
828.
Factorial validity of the Conners' Parent Rating Scale-revised: short form with psychiatric outpatients 总被引:3,自引:0,他引:3
To assess the factorial validity of the 27-item Conners' Parent Rating Scale-Revised: Short Form (CPRS-R:S; Conners, 1997), 100 (50%) male and 100 (50%) female psychiatric outpatients between 5 and 16 years old were rated by a parent. A confirmatory factor analysis of the 18 item ratings from the CPRS-R:S Oppositional, Cognitive Problems, and Hyperactivity scales provided only tentative support for scoring these scales as Conners (1997) recommended. However, an exploratory principal-axis factor analysis with all 27 item ratings found 2 dimensions: 1 dimension was composed of the 6 items in the Oppositional scale, and other dimension contained the remaining 21 items. An attention deficit hyperactivity disorder (ADHD) Total Symptoms scale was constructed by summing the ratings for these 21 symptom ratings, and this scale was found to be as effective as the Hyperactivity scale was in discriminating between youth who were and were not eventually diagnosed with an ADHD. We discuss the results as providing an alternate way of scoring the CPRS-R:S to screen for an ADHD in child and adolescent psychiatric outpatients. 相似文献
829.
The purpose of this study was to explore changes in adolescent self-presentation on the Minnesota Multiphasic Personality Inventory (MMPI; Hathaway & McKinley, 1940) and MMPI-A (Butcher et al., 1992) over a 40-year period. The primary samples used for comparison in this study include 1,235 adolescents, age 14 through 16, derived from the MMPI-A normative sample (Butcher et al., 1992) collected in 1989 and 10,514 adolescents, age 14 through 16, collected in 1948 and 1954 from Hathaway and Monachesi's (1963) study of adolescent personality and behavior. MMPI basic scale and item-level data were also included for 817 adolescents, age 14 through 16, collected by Colligan and Offord (1992) in 1985 as a further comparison. Between-sample analyses at the profile level revealed that adolescents from the MMPI-A normative sample scored significantly higher across basic clinical scales and lower on validity scales L and K than adolescents from the Hathaway and Monachesi (1963) sample, with mean data from the Colligan and Offord (1992) sample typically falling at a midpoint value. Analyses of Harris-Lingoes (Harris & Lingoes, 1955) subscale and item-level data were conducted to provide refined definitions of the contents of scale-level changes. Results were interpreted as reflecting moderate to large changes in response frequencies between eras of data collection, and emphasis was placed on the relatively high frequency of item endorsements by contemporary adolescents in the clinical direction in the MMPI-A normative sample. A series of cautions and limitations are also offered in interpreting these patterns. 相似文献
830.
Grosofsky A Adkins S Bastholm R Meyer L Krueger L Meyer J Torma P 《Perceptual and motor skills》2003,96(1):43-48
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