The Strengths and Difficulties Questionnaire (SDQ): the Factor Structure and Scale Validation in U.S. Adolescents

The Strengths and Difficulties Questionnaire (SDQ) is one of the most commonly used instruments for screening psychopathology in children and adolescents. This study evaluated the hypothesized five-factor structure of the SDQ and examined its convergent validity against comprehensive clinical diagnostic assessments. Data were derived from the National Comorbidity Survey - Adolescent Supplement (NCS-A), a nationally representative sample of U.S. adolescents aged 13 to 18 years. Parents/parent surrogates (n=6,483) was asked to complete a self-administered questionnaire including the SDQ and DSM-IV comprehensive diagnostic information on the participating adolescents. Confirmatory factor analysis (CFA) was conducted to assess the factor structure of the SDQ. The five-factor solution of the SDQ (including emotional, conduct, hyperactivity-inattention, peer relationship, and prosocial) provided a satisfactory fit to the data, and was invariant across sex, age, race/ethnicity and income subgroups. SDQ scores predicted a significantly increased probability of meeting criteria for a DSM-IV disorder, with better prediction for behavior disorders than for mood disorders. Decreasing the SDQ cutoffs to the 80th percentile significantly increased the sensitivity from 39% to 63% for the SDQ Total Difficulties Score, with an expected decrease in specificity from 93% to 87%. This work confirms the five-factor structure of the SDQ in an ethnically and sociodemogrpahically diverse community sample of adolescents. Our findings strengthen empirical evidence for the use of the parent-reported SDQ as a screening tool for DSM-IV behavioral and emotional disorders in adolescents identified in the general population.     

Individual differences in the ability to focus and divide attention

This research deals with individual differences in the ability to focus and divide attention. Eighty-five subjects performed visual search and auditory detection tasks in three conditions: single channel, focused attention, and divided attention. Reaction time (RT) was fastest in the single channel condition, intermediate in the focused attention condition, and longest in the divided attention condition, and these effects were much stronger in the auditory than the visual task. Correlations among RTs in the three conditions were very high within modality (>.88), and lower between modalities (.5 to .6). The correlational data was well fit by a model that included separate factors for the visual and auditory tasks. Measures from the three attentional conditions within each modality loaded equally on these factors. The data provided no evidence for distinct abilities to divide or focus attention.     

Individual differences in long-term memory access

In a study of individual differences in long-term memory access, university undergraduates verified (1) whether an item was a member of a category, (2) whether two items belonged to the same category, and (3) whether two words had the same name. Reaction times from these tasks were correlated with verbal ability, as measured by performance on a standardized test of vocabulary and reading comprehension. A relationship was found between verbal ability and reaction time in the verification tasks. These results are contrasted with those of Hogaboam and Pellegrino (1978), who failed to find such a relationship. The results indicated that the various reaction time measures form a single factor that bears a moderate relationship to reading and vocabulary measures.     

The effect of parental modeling of anxious behaviors and cognitions in school-aged children: An experimental pilot study

The current study tested: (1) the impact of parental modeling of anxious behaviors and cognitions on child anxiety level, anxious cognitions, desired avoidance, and objective performance using an experimental paradigm; and (2) whether the impact of parental modeling of anxious behaviors and cognitions differed by parent gender. Twenty-five parents (a random selection of 12 male and 13 female parents) participated with one of their children (ages 8-12 years; 56.0% male; 76.0% Caucasian). All children experienced two test conditions: an anxious condition in which their parent was trained to act anxiously before a planned spelling test and a non-anxious condition in which their parent was trained to act in a relaxed and confident manner before a planned spelling test. Results showed that, regardless of parent gender, children endorsed higher anxiety levels, anxious cognitions, and desired avoidance of the spelling test in the anxious relative to the non-anxious condition. Parental modeling of anxiety did not affect child spelling performance. Significant interaction effects indicated that fathers had a stronger impact on child anxiety level and cognitions than did mothers. Results highlight the importance of parental modeling and the potential role of both mothers and fathers in prevention and treatment for child anxiety.     

Ethnic differences in clinical presentation of depression in adult women

This study examined ethnic differences in self-report and interviewer-rated depressive symptoms and estimated the contributions of sociodemographic and psychosocial factors in predicting severity of depression. One hundred twenty-five clinically depressed African American (n = 46), Caucasian (n = 36), and Latina (n = 43) women were recruited. After controlling for differences in socioeconomic status, African American women reported more symptoms of distress and Latinas were rated as significantly more depressed than the other groups. However, these ethnic differences were not moderated by either education or employment. Finally, hierarchical regression analysis indicated that severity of depression was predicted by low education, being single, being Latina, high perceived stress, and feelings of hopelessness. Additional research is needed to validate these results and to investigate their clinical significance.     

The cortex in multidimensional space: where do cortical areas come from?

The concept of a cortical ‘area’ as a discrete phylogenetic, developmental and computational unit is evaluated. Evidence including the comparative organization of the forebrain in vertebrates, the organization of cortex in different mammals, the scaling of the areas of the isocortex in mammals, and the early molecular differentiation of the cortex all suggest a special status for the primary sensory cortical areas, particularly the visual cortex. Furthermore, the overlapping gradients of early molecular expression and the patterning of cortical structure and connectivity by thalamic input suggest a new view of cortical organization that is different from the traditional view of a developmentally mosaic cortex; this view proposes that distinct cortical areas arise combinatorily from the multiple overlapping processes imposed upon the developing cortex.     

Rapid and persistent suppression of feeding behavior induced by sensitization training in Aplysia

In Aplysia, noxious stimuli induce sensitization of defensive responses. However, it remains largely unknown whether such stimuli also alter nondefensive behaviors. In this study, we examined the effects of noxious stimuli on feeding. Strong electric shocks, capable of inducing sensitization, also led to the suppression of feeding. The use of multiple training protocols revealed that the time course of the suppression of feeding was analogous to that of sensitization. In addition, the suppression of feeding was present only at the time points in which sensitization was expressed. These results suggest that, in Aplysia, noxious stimuli may produce concurrent changes in neural circuits controlling both defensive and nondefensive behaviors.     

Review Article: Chiari Type I Malformation with or Without Syringomyelia: Prevalence and Genetics

Chiari type I malformation has traditionally been defined as a downward herniation of the cerebellar tonsils of 5 mm through the foramen magnum and it is likely associated with a volumetrically reduced posterior fossa. Syringomyelia is commonly associated with Chiari type I malformation. We estimate the prevalence of these two conditions and determine that they are more common than previously expected. We identify the genetic syndromes associated with some cases of Chiari type I malformation, and we provide evidence in favor of a genetic hypothesis for at least a subset of the nonsyndromic cases.