Genetic and environmental effects on stuttering: a twin study from Finland

The present study explored the prevalence of self-reported stuttering in a Finnish twin population and examined the extent to which the variance in liability to stuttering was attributable to genetic and environmental effects. We analyzed data of 1728 Finnish twins, born between 1961 and 1989. The participants were asked to complete a questionnaire on speech, language, and voice. In two of the questions they were asked to report the occurrence of childhood and present stuttering of their own and that of their sibling. According to the results, 2.3% (52) of the participants were reported to have stuttered as children and 28.8% of them (15) were reported to continue to stutter in adulthood. There was no significant gender difference in the prevalence of stuttering in either childhood or adulthood. For childhood stuttering, the tetrachoric correlation was higher for monozygotic pairs (r=.74) than for dizygotic pairs (r=.27). By means of structural equation modeling it was found that 82% of the variance in liability to childhood stuttering was attributable to additive genetic effects, with the remaining 18% due to non-shared environmental effects. In conclusion, the results of the present study confirm findings from prior studies and support a strong genetic and only a moderate non-shared environmental effect on stuttering. Potential small differences in the prevalence of stuttering in different populations are suggested by our data. EDUCATIONAL OBJECTIVES: The reader will be able to recognize the contribution of genetic and environmental effects on stuttering.     

Perspectives of children and adolescents on the perceived determinants of physical activity during recess

Promotion of healthy lifestyles in youth focuses on school-based interventions with the aim to increase physical activity (PA) during school days. Drawing on seventeen focus group discussions from three purposively selected Estonian schools, we explored factors that perceivably affect students’ recess physical activity (RPA). Both inductive and deductive principles of data analysis were used to extract major and subthemes related to factors that inhibit or enhance RPA. Participants identified barriers and facilitators to recess PA as originating mainly from physical and organizational school environment. Also, unsuitable weather was described as a barrier to being active. Additionally, feelings, behavioral and normative beliefs were described as constraining or facilitating RPA. Results highlighted two culture-specific unique perceived determinants of RPA that need to be addressed during the development of school-based interventions to increase PA.     

Personality and affectivity characteristics associated with eating disorders: a comparison of eating disordered, weight-preoccupied, and normal samples.

The purpose of this study was to assess the relative contribution of personality and emotional experience to self-reported eating attitudes in a group of patients with clinically diagnosed eating disorders, a weight-reduction training group (Weight Watchers), and a control group without body weight problems. Participants in this study (N = 114) completed Estonian versions of the Eating Disorder Inventory-2 (EDI-2; Garner, 1991), NEO Personality Inventory (Costa & McCrae, 1989), and Positive Affect and Negative Affect Schedule, Expanded Form (Watson & Clark, 1994). Data demonstrated validity of the Estonian version of EDI-2 in its ability to identify problems on a continuum of disordered eating behavior. Among the Big Five personality dimensions, Neuroticism made the largest contribution to EDI-2 subscales. Two other dimensions, Openness to Experience and Conscientiousness, also predispose individuals to eating problems. Personality traits made a larger contribution to the self-reported eating pathology than the self-rated effects experienced during the last few weeks. It was argued that personality dispositions have a larger relevancy in the etiology of eating disorders than emotional state.     

Selection-for-action in visual search

Grasping an object rather than pointing to it enhances processing of its orientation but not its color. Apparently, visual discrimination is selectively enhanced for a behaviorally relevant feature. In two experiments we investigated the limitations and targets of this bias. Specifically, in Experiment 1 we were interested to find out whether the effect is capacity demanding, therefore we manipulated the set-size of the display. The results indicated a clear cognitive processing capacity requirement, i.e. the magnitude of the effect decreased for a larger set size. Consequently, in Experiment 2, we investigated if the enhancement effect occurs only at the level of behaviorally relevant feature or at a level common to different features. Therefore we manipulated the discriminability of the behaviorally neutral feature (color). Again, results showed that this manipulation influenced the action enhancement of the behaviorally relevant feature. Particularly, the effect of the color manipulation on the action enhancement suggests that the action effect is more likely to bias the competition between different visual features rather than to enhance the processing of the relevant feature. We offer a theoretical account that integrates the action-intention effect within the biased competition model of visual selective attention.