Neural Correlates of Reward Processing in Adolescents With a History of Inhibited Temperament

ABSTRACT— Functional imaging data were acquired during performance of a reward-contingency task in a unique cohort of adolescents (ages 14–18 years) who were characterized since infancy on measures of temperamental behavioral inhibition. Neural activation was examined in striatal structures (nucleus accumbens, putamen, caudate) with a known role in facilitating response to salient reward-related cues. Adolescents with a history of behavioral inhibition, relative to noninhibited adolescents, showed increased activation in the nucleus accumbens when they believed their selection of an action would affect reward outcome. Neural responses did not differ between the two groups when participants made a prespecified response that they knew would result in reward or when they produced random motor responses that they knew would not be rewarded. These results link inhibited temperament and perturbed neural responses to reward-contingency cues.     

Mushroom Bodies Suppress Locomotor Activity in Drosophila melanogaster

Locomotor activity of single, freely walking flies in small tubes is analyzed in the time domain of several hours. To assess the influence of the mushroom bodies on walking activity, three independent noninvasive methods interfering with mushroom body function are applied: chemical ablation of the mushroom body precursor cells; a mutant affecting Kenyon cell differentiation (mushroom body miniature¹); and the targeted expression of the catalytic subunit of tetanus toxin in subsets of Kenyon cells. All groups of flies with mushroom body defects show an elevated level of total walking activity. This increase is attributable to the slower and less complete attenuation of activity during the experiment. Walking activity in normal and mushroom body-deficient flies is clustered in active phases (bouts) and rest periods (pauses). Neither the initiation nor the internal structure, but solely the termination of bouts seems to be affected by the mushroom body defects. How this finding relates to the well-documented role of the mushroom bodies in olfactory learning and memory remains to be understood.     

Substructural Logics in Natural Deduction

Extensions of Natural Deduction to Substructural Logics of IntuitionisticLogic are shown: Fragments of Intuitionistic Linear, Relevantand BCK Logic. Rules for implication, conjunction, disjunctionand falsum are defined, where conjunction and disjunction respectcontexts of assumptions. So, conjunction and disjunction areadditive in the terminology of linear logic. Explicit contractionand weakening rules are given. It is shown that conversionsand permutations can be adapted to all these rules, and thatweak normalisation and subformula property holds. The resultsgeneralise to quantification.     

Attentive processing of threat and adult attachment: a dot-probe study

We examined selective attention to threat stimuli as a function of individual differences in adult attachment. Participants completed a dot-probe task in which a general threat word, attachment-related threat word, general positive or attachment-related positive word was presented together with a neutral word. Results showed that attachment anxiety and avoidance were associated with an attentional bias away from attachment threat words. This attentional avoidance effect was best predicted by the interaction between attachment anxiety and avoidance and not by their unique main effects. The findings are discussed in terms of attachment theory and its relation to attentional biases observed in psychopathology.     

A perfectly staged 'concerted action' against psychoanalysis

An eyewitness account provides evidence of a significant clandestine effort to neutralize the legitimacy and authority of psychoanalysis. In a letter, the witness confirms the existence of a perfectly staged concerted action among German psychiatrists against Freud's influence in 1913. Their congress in Breslau was meant to present the united front of German psychiatrists, who were going on record as being against psychoanalysis and, in that context, to give Eugen Bleuler, a leading psychiatrist, whose (however half-hearted) support for psychoanalysis had alarmed his colleagues, a public opportunity for back-pedalling. The letter shows that Freud and his allies were not the only ones who tried to manage an intellectual movement by using informal networks and 'behind the scenes' manoeuvring.