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Evidence for semantic preview benefit (PB) from parafoveal words has been elusive for reading alphabetic scripts such as English. Here we report semantic PB for noncompound characters in Chinese reading with the boundary paradigm. In addition, PBs for orthographic relatedness and, as a numeric trend, for phonological relatedness were obtained. Results are in agreement with other research suggesting that the Chinese writing system is based on a closer association between graphic form and meaning than is alphabetic script. We discuss implications for notions of serial attention shifts and parallel distributed processing of words during reading.
Is a specific disorder of arithmetic skills as common as reading/spelling disorder?Background: Referring to the prevalence rates of learning disorders in the research literature, the numbers of mathematics disorder and reading/ spelling disorder are often reported to be identical. However, the correlation between intelligence level and reading/ spelling skills is much weaker than between intelligence and arithmetic skills. If the same definition criterion is applied to both disorders, a lower prevalence rate for mathematics disorder should be expected. Objective: Are there differences in the prevalence estimates for learning disorders depending on the definition criterion? Method: A large representative sample of German students (N = 1970) was used to review the hypothesis. Results: Depending on the definition criterion, we could show a prevalence range of mathematics disorder between 0.1% and 8.1% in the same sample. Using the same definition criterion for both learning disorders, there are two to three times as many students with reading/spelling disorder than those with mathematics disorder. Discussion: Whenever children with reading/spelling disorder are compared to children with mathematics disorder, the same definition criterion has to be applied.
Prävention kindlichen übergewichts : elterliche Selbstwirksamkeit und Handlungsergebniserwartungen
(2009)
Adipositas ist ein ernstzunehmendes gesundheitliches Problem, welches das physische und psychosoziale Wohlbefinden von Kindern und deren Eltern beeintraechtigt und somit wirksamer praeventiver Ansaetze bedarf. Dabei ist es bedeutsam, welche Barrieren, Anreize und Selbstwirksamkeitserwartungen Eltern fuer oder gegen die Teilnahme an solchen Programmen entscheiden lassen. Ziel der Studie war es zu untersuchen, wie Muetter ihre Selbstwirksamkeits- und Handlungsergebniserwartungen beschreiben und inwieweit sich soziodemografische Aspekte auf diese Einschaetzungen auswirken. Insgesamt wurden 219 Muetter von Kindern im Alter von 3-6 Jahren befragt. Mehr als die Haelfte der befragten Muetter waren uebergewichtig bzw. adipoes sowie 12% der Kinder. Es ergaben sich weder fuer das Alter und das Geschlecht des Kindes noch fuer das Familieneinkommen Unterschiede in den Handlungsergebniserwartungen. Muetter mit geringerer Bildung nahmen weniger Anreize wahr und Muetter mit uebergewichtigen Kindern sahen weniger Barrieren fuer eine Programmteilnahme. uebergewichtige Muetter dagegen bewerteten die Barrieren und Anreize hoeher als normalgewichtige Muetter. Hinsichtlich der Selbstwirksamkeit ergaben sich ebenfalls Unterschiede bezueglich der Bildung und des Gewichts der Mutter sowie des Kindes. Im Vorfeld einer Intervention sollte ein Beratungsgespraech bezogen auf die muetterlichen Erwartungen stattfinden, um die Teilnahmebereitschaft und den Programmerfolg zu unterstuetzen.
OBJECTIVE: To examine factors associated with the maternal perception of the weight status in related and unrelated children and to examine whether associated health risks for children's physical and mental health are recognized. PATIENTS AND METHODS: Two hundred nineteen mothers with children between 3 and 6 years of age took part in this study. The participating mothers were recruited from inpatient clinics and kindergartens. Parents were presented with 9 silhouettes representing different age- and gender-specific BMI percentiles. Demographic and weight-related variables were assessed with regard to their influence on the accuracy of the maternal weight estimation in general and for their own child. RESULTS: Of the participating mothers, 64.5% identified the overweight silhouettes of preschool- aged children correctly. However, only 48.8% of the mothers identified the overweight silhouettes associated with an increased risk for physical health problems, and 38.7% identified the silhouettes associated with an increased mental health risk. Mothers with a lower educational background were more likely to misclassify the overweight silhouettes and underestimate the associated health problems. For their own child, only 40.3% of the mothers chose silhouettes that were in agreement with the objective weight status of their child. This underestimation was associated with a higher maternal and child weight status but not with a general inability to identify the weight status of children. CONCLUSIONS: Identifying unrelated overweight silhouettes is influenced by maternal education level, whereas estimating their own child's weight status is influenced by the weight status of the mother and the child. Hence, feedback on the child's risk to become overweight is necessary to increase maternal risk awareness and willingness to take part in prevention programs.
It has recently been demonstrated that the presentation of visual oddballs induces a prolonged inhibition of microsaccades. The amplitude of the P300 component in event-related potentials (ERPs) has been shown to be sensitive to the category (target vs. nontarget) of the eliciting stimulus, its overall probability, and the preceding stimulus sequence. In the present study we further specify the functional underpinnings of the prolonged microsaccadic inhibition in the visual oddball task, showing that the stimulus category, the frequency of a stimulus, and the preceding stimulus sequence influence microsaccade rate. Furthermore, by co-recording ERPs and eye movements, we were able to demonstrate that, despite being largely sensitive to the same experimental manipulation, the amplitude of P300 and the microsaccadic inhibition predict each other only weakly.
It has recently been demonstrated that the presentation of a rare target in a visual oddball paradigm induces a prolonged inhibition of microsaccades. In the field of electrophysiology, the amplitude of the P300 component in event-related potentials (ERP) has been shown to be sensitive to the stimulus category (target vs. non target) of the eliciting stimulus, its overall probability, and the preceding stimulus sequence. In the present study we further specify the functional underpinnings of the prolonged microsaccadic inhibition in the visual oddball task, showing that the stimulus category, the frequency of a stimulus and the preceding stimulus sequence influence microsaccade rate. Furthermore, by co-recording ERPs and eye-movements, we were able to demonstrate that, despite being largely sensitive to the same experimental manipulation, the amplitude of P300 and the microsaccadic inhibition predict each other very weakly, and thus constitute two independent measures of the brain’s response to rare targets in the visual oddball paradigm.
Active motor processes are present in many sensory systems to enhance perception. In the human visual system, miniature eye movements are produced involuntarily and unconsciously when we fixate a stationary target. These fixational eye movements represent self-generated noise which serves important perceptual functions. Here we investigate fixational eye movements under the influence of external noise. In a two-choice discrimination task, the target stimulus performed a random walk with varying noise intensity. We observe noise-enhanced discrimination of the target stimulus characterized by a U-shaped curve of manual response times as a function of the diffusion constant of the stimulus. Based on the experiments, we develop a stochastic information-accumulator model for stimulus discrimination in a noisy environment. Our results provide a new explanation for the constructive role of fixational eye movements in visual perception.
The aim of this study was to investigate the effects of three different forms of strategy instruction on 210 elementary-school students' reading comprehension. Students were assigned to any one of three intervention conditions or to a traditional instruction condition (control condition). Training students were taught four reading strategies (summarizing, questioning, clarifying, predicting) and practiced these strategies in small groups (reciprocal teaching), pairs, or instructor-guided small groups. At both the post- and follow-up test the intervention students attained higher scores on an experiment-developed task of reading comprehension and strategy use than the control students who received traditional instruction. Furthermore, students who practiced reciprocal teaching in small groups outperformed use than the control students who received traditional instruction groups on a standardized reading comprehension test.
R. Sekuler, P. Tynan, and E. Levinson (1973) found that when 2 characters are presented side-by-side with a short onset asynchrony, subjectively, they often appear in a "first-left, then-right" order. The authors of this article conducted 6 experiments in which observers judged the temporal order (TOJs) in which 2 digits were presented. They found a consistent TOJ benefit (larger d') when the numerically smaller digit was presented first, even though this semantic information was irrelevant to the task and unrelated to the correct response. They concluded that digits located to the left of the mental number line are transmitted faster to a central comparison stage, which represents an "internal counterpart" to the Sekuler et al. (1973) finding regarding external locations. A corresponding benefit is found for letters pairs (e.g., A-Z) and also for mixed digit-letter pairs (e.g., I-Z).
Previous studies that have examined the relationship between implicit and explicit motive measures have consistently found little variance overlap between both types of measures regardless of thematic content domain (i.e., power, achievement, affiliation). However, this independence may be artifactual because the primary means of measuring implicit motivescontent-coding stories people write about picture cuesare incommensurable with the primary means of measuring explicit motives: having individuals fill out self-report scales. To provide a better test of the presumed independence between both types of measures, we measured implicit motives with a Picture Story Exercise (PSE; McClelland, Koestner, Weinberger, 1989) and explicit motives with a cue- and response-matched questionnaire version of the PSE (PSE-Q) and a traditional measure of explicit motives, the Personality Research Form (PRF; Jackson, 1984) in 190 research participants. Correlations between the PSE and the PSE-Q were small and mostly nonsignificant, whereas the PSE- Q showed significant variance overlap with the PRF within and across thematic domains. We conclude that the independence postulate holds even when more commensurable measures of implicit and explicit motives are used.
Es werden Befunde aus einer prospektiven Laengsschnittstudie praesentiert, in der 321 Probanden im Alter von 8, 13, 18 und 25 Jahren untersucht werden konnten; ihre Dunkelfelddelinquenz wurde mit 18 und 25 Jahren erfasst. Wir suchten nach Assoziationen zur Delinquenzentwicklung und erwarteten Unterschiede zwischen auf das Jugendalter beschraenkter gegenueber ins fruehe Erwachsenenalter fortgesetzter sowie spaet, d.h. nach dem Alter von 18 Jahren, beginnender Delinquenz. Wir fanden gemeinsame Risikofaktoren und fuer die drei Verlaufstypen spezifische Risikokonstellationen, die eher im Jugendalter als in der Kindheit identifiziert wurden. Widrige familiaere Bedingungen, Entwicklungsverzoegerungen und psychische Stoerungen scheinen mit Delinquenz als eher persistentem Verhalten assoziiert.
Recent evidence suggests that heterogeneity in the age at onset could explain the inconsistent findings of association studies relating the dopamine transporter (DAT1) gene with alcohol and nicotine consumption. The aim of this study was to examine interactions between two DAT1 polymorphisms and different initiation ages with regard to alcohol and tobacco consumption levels and dependence. Two hundred and ninety-one young adults (135 males, 156 females) participating in the Mannheim Study of Children at Risk were genotyped for the 40-bp variable number of tandem repeats (VNTR) and rs27072 polymorphisms of DAT1. Age at initiation was assessed at age 15 and 19 years. Information about current alcohol and tobacco consumption was obtained at age 19 years using self-report measures and structured interviews. Results suggest that age at onset of intensive consumption moderated the association of the DAT1 gene with early adult substance use and dependence, revealing a DAT1 effect only among individuals homozygous for the 10r allele of the 40-bp VNTR who had started daily smoking or being intoxicated early in life. Equally, carriers of the T allele of the rs27072 polymorphism reporting an early age at first intoxication showed higher current alcohol consumption at age 19 years. In contrast, no interaction between rs27072 and the age at first cigarette with regard to later smoking was observed. These findings provide evidence that the DAT1 gene interacts with an early heavy or regular drug exposure of the maturing adolescent brain to predict substance (ab)use in young adulthood. Further studies are required to confirm these findings.
Motivation
(2009)
The method of twin surrogates has been introduced to test for phase synchronization of complex systems in the case of passive experiments. In this paper we derive new analytical expressions for the number of twins depending on the size of the neighborhood, as well as on the length of the trajectory. This allows us to determine the optimal parameters for the generation of twin surrogates. Furthermore, we determine the quality of the twin surrogates with respect to several linear and nonlinear statistics depending on the parameters of the method. In the second part of the paper we perform a hypothesis test for phase synchronization in the case of experimental data from fixational eye movements. These miniature eye movements have been shown to play a central role in neural information processing underlying the perception of static visual scenes. The high number of data sets (21 subjects and 30 trials per person) allows us to compare the generated twin surrogates with the "natural" surrogates that correspond to the different trials. We show that the generated twin surrogates reproduce very well all linear and nonlinear characteristics of the underlying experimental system. The synchronization analysis of fixational eye movements by means of twin surrogates reveals that the synchronization between the left and right eye is significant, indicating that either the centers in the brain stem generating fixational eye movements are closely linked, or, alternatively that there is only one center controlling both eyes.
Contrary to common wisdom, fixations are a dynamically rich behavior, composed of continual, miniature eye movements, of which microsaccades are the most salient component. Over the last few years, interest in these small movements has risen dramatically, driven by both neurophysiological and psychophysical results and by advances in techniques, analysis, and modeling of eye movements. The field has a long history but a significant portion of the earlier work has gone missing in the current literature, in part, as a result of the collapse of the field in the 1980s that followed a series of discouraging results. The present review compiles 60 years of work demonstrating the unique contribution of microsaccades to visual and oculomotor function. Specifically, the review covers the contribution of microsaccades to (1) the control of fixation position, (2) the reduction of perceptual fading and the continuity of perception, (3) the generation of synchronized visual transients, (4) visual acuity, (5) scanning of small spatial regions, (6) shifts of spatial attention, (7) resolving perceptual ambiguities in the face of multistable perception, as well as several other functions. The accumulated evidence demonstrates that microsaccades serve both perceptual and oculomotor goals and although in some cases their contribution is neither necessary nor unique, microsaccades are a malleable tool conveniently employed by the visual system.
BACKGROUND: Feedback from the body is assumed to be altered in depression. Nevertheless, empirical studies investigating this assumed relationship remain sparse. This study aimed to examine interrelations between the ability to perceive heartbeats accurately (interoceptive awareness), depressive symptoms, and anxiety in healthy participants. METHODS: A well-validated heartbeat perception task to measure interoceptive awareness together with two questionnaires indexing anxiety and depression were administered to 119 participants. RESULTS: As main results we observed a negative correlation between heartbeat perception and depression. Only when focussing on high anxiety levels this negative correlation coefficient between depression and interoception remained significant. CONCLUSIONS: Our results highlight the possible relationship between depressive symptoms and interoceptive awareness and may have further implications for theoretical models of anxiety disorders and their treatment. Further research is required to examine the potential consequences of altering interoceptive awareness in healthy subjects in relation to depression and anxiety.