A combined fMRI and DTI examination of functional language lateralization and arcuate fasciculus structure: Effects of degree versus direction of hand preference

The present study examined the relationship between hand preference degree and direction, functional language lateralization in Broca’s and Wernicke’s areas, and structural measures of the arcuate fasciculus. Results revealed an effect of degree of hand preference on arcuate fasciculus structure, such that consistently-handed individuals, regardless of the direction of hand preference, demonstrated the most asymmetric arcuate fasciculus, with larger left versus right arcuate, as measured by DTI. Functional language lateralization in Wernicke’s area, measured via fMRI, was related to arcuate fasciculus volume in consistent-left-handers only, and only in people who were not right hemisphere lateralized for language; given the small sample size for this finding, future investigation is warranted. Results suggest handedness degree may be an important variable to investigate in the context of neuroanatomical asymmetries.     

Support for lateralization of the Whorf effect beyond the realm of color discrimination

Recent work has shown that Whorf effects of language on color discrimination are stronger in the right visual field than in the left. Here we show that this phenomenon is not limited to color: The perception of animal figures (cats and dogs) was more strongly affected by linguistic categories for stimuli presented to the right visual field than those presented to the left. Moreover, the magnitude of the visual field asymmetry was reduced when demands on verbal working memory were increased by a secondary task. This reduction did not occur when the secondary task imposed demands on spatial working memory. Taken together, these results demonstrate that the lateralized Whorf effect may be quite general, reflecting an interaction of linguistic and perceptual codes primarily in the left hemisphere.     

God and the government: testing a compensatory control mechanism for the support of external systems

The authors propose that the high levels of support often observed for governmental and religious systems can be explained, in part, as a means of coping with the threat posed by chronically or situationally fluctuating levels of perceived personal control. Three experiments demonstrated a causal relation between lowered perceptions of personal control and the defense of external systems, including increased beliefs in the existence of a controlling God (Studies 1 and 2) and defense of the overarching socio-political system (Study 4). A 4th experiment (Study 5) showed the converse to be true: A challenge to the usefulness of external systems of control led to increased illusory perceptions of personal control. In addition, a cross-national data set demonstrated that lower levels of personal control are associated with higher support for governmental control (across 67 nations; Study 3). Each study identified theoretically consistent moderators and mediators of these effects. The implications of these results for understanding why a high percentage of the population believes in the existence of God, and why people so often endorse and justify their socio-political systems, are discussed.     

Cannabiskonsum und -missbrauch bei Jugendlichen und jungen Erwachsenen

After a long time of growth current studies on representative samples of adolescents indicate that the number of adolescent cannabis users in Germany is possibly decreasing. However, it may be presumptuous to expect a similar trend concerning the number of clients with cannabis-related disorders. Even if there is in fact a downward trend which is not yet proven, the rapidly growing number of clients presenting with these disorders in recent years cannot be explained by a similar growth in the number of regular cannabis users. Treatment centres should therefore expect a further inreasing number of especially male adolescents and young adults seeking help for problems related to cannabis use. The development, evaluation and implementation of specific treatment options concerning cannabis use disorders will be increasingly needed in the future. Cognitive-behavioral and motivational interventions have been shown to be evidence-based treatments. The paper describes some promising or already successful treatment approaches and related research projects in Germany.     

Effect of Age and Level of Cognitive Function on Spontaneous and Exploratory Behaviors in the Beagle Dog

Cognitively characterized young and aged beagle dogs were administered six different spontaneous behavior tests, which provided measures of locomotion, exploration, and social interaction. Consistent with our previous findings, we obtained no overall effect of age on locomotion. We did find, however, that for the aged dogs locomotion correlated with level of cognitive function, being lowest in age-unimpaired dogs and highest in impaired dogs. Exploratory behavior, as measured by response to novelty, varied with age, with young dogs scoring the highest. Young dogs spent more time with novel toys and a person, responded more to a silhouette of a dog, and interacted more with a model dog compared to aged dogs. Among the aged dogs, age-unimpaired dogs spent the greatest amount of time sitting or standing beside a person whereas age-impaired dogs spent the most time reacting to a reflection in a mirror. The age-impaired dogs show undirected, stereotypical types of behavioral patterns. These differences in activity patterns may be linked to underlying age-associated neuropathology.