Dimensional complexity and power spectral measures of the EEG during functional versus predicative problem solving

Electroencephalograms were recorded in 22 men while solving tasks of visual-pattern completion and during mental relaxation. They were primed (by foregoing trials) to solve these tasks either in a predicative or functional mode of thinking. Predicative thinking required that in order to complete the pattern the subject had to get involved with the logic of the static structure of the pattern and therefore had to recognize the recurrence of certain features of the elements (e.g., shape, color, and size). Functional thinking required involvement in a dynamic reading of the logic of the pattern and therefore to search for operations and actions to be performed on the pattern elements (e.g., pushing, mirroring, and rotating). The EEG complexity during predicative thinking decreased in comparison to functional thinking and mental relaxation, with this reduction being most pronounced over the right parietal cortex. A reduction in dimensional complexity during functional thinking as compared to mental relaxation, which was concentrated over the left central cortex, although significant, was less clear. The reduced EEG complexity during predicative thought, dominant over the right hemisphere, could reflect increased competitive inhibition among respective cortical neuron assemblies in association with the visual analysis of static element features, converging upon those predicates relevant for the solution.     

The role of mental relaxation in experimental desensitization

Certain evidence indicates that training in peripheral muscle relaxation is not an essential factor in the successful experimental desensitization of phobias. Rachman (1968) has suggested that a sense of calmness or mental relaxation is the necessary component and that all the preliminary training techniques leading to successful desensitization, have, as the basis for their success, the inadvertent induction of this state of mental calmness. The direct induction of mental relaxation then, ought to be at least as effective an adjunct to desensitization as training in muscle relaxation. Using spider phobia as the target behaviour, the present study compared the effectiveness of (a) hierarchy presentation paired with deep muscle relaxation; (b) hierarchy presentation paired with instructions to feel calm and relaxed and alternated with imagining a pleasant scene; (c) a combination of these two procedures paired with hierarchy presentation; and (d) a placebo control procedure. The treatment groups all improved significantly more than controls and there there were no differences between treatments. The results were seen as offering strong support of Rachman's position. Both theoretical and practical implications of the results are discussed with consideration being given to the nature of “mental calmness”.     

Birth month and suicide among major league baseball players

We examined the association between month of birth and completed suicides among major league baseball players (N = 76). More than twice as many players born in August committed suicide (N = 19) than any other birth month. This association was statistically significant when birth month was corrected for differences in days of the month. The differences were even larger when expressed in terms of birth month for those committing suicides divided by number of major league players born in each month. The association between birth month and suicide raises the possibility that prenatal factors may influence the inclination for suicide later in life.     

Educational attainment and suicide rates in the United States

We examined the relationship between educational attainment and suicide rate in the United States for 2001. Suicide rates, adjusted for age, were compared with percentage of college graduates, median household income, and poverty in 50 states in 2001. The correlations of suicide rates with educational attainment and median household income were both negative and statistically significant. Poverty was not significantly related to suicide rates. We concluded that higher education and income were associated with a decrease in suicide rates in 2001. Data from other years require examination for this conclusion to be generalizable.     

Testing comprehension abilities in users of British Sign Language following CVA

Recent imaging (e.g., MacSweeney et al., 2002) and lesion (Hickok, Love-Geffen, & Klima, 2002) studies suggest that sign language comprehension depends primarily on left hemisphere structures. However, this may not be true of all aspects of comprehension. For example, there is evidence that the processing of topographic space in sign may be vulnerable to right hemisphere damage (e.g., Hickok, Say, Bellugi, & Klima, 1996), and the influence of iconicity on comprehension has yet to be explored. In this study, comprehension testing was conducted with 15 signers with unilateral brain damage, and with elderly Deaf controls. Four tests were administered: a test of iconic and non-iconic noun comprehension, a test of verb and sentence comprehension, a test of locative sentence comprehension, and a test of classifier comprehension. All tests were administered in British Sign Language (BSL), a language that has only recently been explored with lesioned signers (see Atkinson, Marshall, Thacker, & Woll, 2004; Marshall, Atkinson, Thacker, Woll, & Smulevitch, 2004; Marshall, Atkinson, Woll, & Thacker, in press). People with left hemisphere damage were impaired relative to controls on all tests. Those with right hemisphere damage performed well in the first two tests, but were impaired on locative sentences and classifiers. Neither group showed any effect of iconicity. The results shed further light on the laterality of sign language comprehension.     

Assessing aggression in adolescent romantic relationships: can we do it better?

Almost all research on aggression in adolescent romantic relationships makes use of 1-time, retrospective assessment methods. In the present research, the authors compared data on the experience of adolescent relationship aggression (physical aggression and threatening behavior) collected from 125 high school students via 2 methods: (a) a 1-time, 2-month retrospective assessment and (b) a cumulative method based on four 2-week retrospective assessments, each spaced 2 weeks apart. For the cumulative method, data from the 4 assessments were aggregated to cover the same time period as the single, 2-month retrospective assessment. A greater proportion of the sample (48.0%) reported experiencing physical aggression using the cumulative method compared with the single, 2-month retrospective method (27.0%). The prevalence of threatening behavior was also higher using the cumulative method (48.8% vs. 24.8%). Adolescent trauma and anxiety symptoms correlated more strongly with physical aggression data derived from the cumulative method than from the 1-time assessment method.     

Validity of test score interpretations for three self-concept measures based on differing theoretical models

Three theoretical models have been proposed to represent self-concept: (a) unidimensional; (b) multidimensional; (c) multidimensional hierarchical. Inventories have been developed under each of the three competing theoretical models; which model best represents self-concept is unclear. Typically, self-concept construct validation has utilized various approaches including correlational, multitrait-multimethod, and factor analytic methods. Another method, however, for assessing validity would be to determine the consequences of score interpretations using different measures specific to each of the theoretical models. This paper examined Messick's notion (1989) of the validity of test-score interpretations as applied to three of the most widely used measures derived under each of the three different theoretical models of self-concept. Results suggest that overall multidimensional measures are more consistent in classifying individual's self-concept than unidimensional measures.