Does Evidence-Based Medicine Apply to Psychiatry?

Evidence-based psychiatry (EBP) has arisen through the application of evidence-based medicine (EBM) to psychiatry. However, there may be aspects of psychiatric disorders and treatments that do not conform well to the assumptions of EBM. This paper reviews the ongoing debate about evidence-based psychiatry and investigates the applicability, to psychiatry, of two basic methodological features of EBM: prognostic homogeneity of clinical trial groups and quantification of trial outcomes. This paper argues that EBM may not be the best way to pursue psychiatric knowledge given the particular features of psychiatric disorders and their treatments. As a result, psychiatry may have to develop its own standards for rigour and validity. This paper concludes that EBM has had a powerful influence on how psychiatry investigates and understands mental disorders. Psychiatry could influence EBM in return, reshaping it in ways that are more clinically useful and congruent with patients’ needs.     

Emotional distraction unbalances visual processing

Brain mechanisms used to control nonemotional aspects of cognition may be distinct from those regulating responses to emotional stimuli, with activity of the latter being detrimental to the former. Previous studies have shown that suppression of irrelevant emotional stimuli produces a largely right-lateralized pattern of frontal brain activation, thus predicting that emotional stimuli may invoke temporary, lateralized costs to performance on nonemotional cognitive tasks. To test this, we briefly (85 ms) presented a central, irrelevant, expressive (angry, happy, sad, or fearful) or neutral face 100 ms prior to a letter search task. The presentation of emotional versus neutral faces slowed subsequent search for targets appearing in the left, but not the right, hemifield, supporting the notion of a right-lateralized, emotional response mechanism that competes for control with nonemotional cognitive processes. Presentation of neutral, scrambled, or inverted neutral faces produced no such laterality effects on visual search response times.     

Reduced spiking in entorhinal cortex during the delay period of a cued spatial response task

Intrinsic persistent spiking mechanisms in medial entorhinal cortex (mEC) neurons may play a role in active maintenance of working memory. However, electrophysiological studies of rat mEC units have primarily focused on spatial modulation. We sought evidence of differential spike rates in the mEC in rats trained on a T-maze, cued spatial delayed response task. Animals begin at the base of the T-maze where a 1-sec white noise and visual light cue are presented on the left or right side of the maze. Rats are rewarded for responding toward the cued direction. In correct trials, we observed decreased spike rates during the delay period, the time interval between cue presentation and reward delivery. Firing-rate histograms show significant decreases during the delay period compared to 5-sec windows from both pre-cue and post-reward periods. We analyzed how running speed and trajectory specificity correlated to spike rate. Twice as many cells were responsive to cue alone compared to running speed. Trajectory specificity did not relate significantly to firing rate. Decreased spike rate may reflect active maintenance in other structures inhibiting mEC. Alternately, the reduction may reflect decreases in background activity during enhanced attention and cholinergic modulation. Lastly, animals often ran through the T-maze choice-point with varying speed. We calculated the spatial posterior probability density from spike rates during these choice-point passes. Slow passes through the choice point were characterized by greater probability of decoding to the reward locations on correct trials compared to quick passes on the maze consistent with similar "look-ahead" properties previously reported in the hippocampus and ventral striatum.     

A new high-pressure phase transition in a zirconium-niobium alloy

It is reported for the first time that a g M y transformation can be induced in a g -stabilized zirconium alloy subjected to shock pressure. The y phase formed in the g matrix has been found to have a plate shape akin to martensitic plates. The lattice correspondence between the g and y structures has been found to be the same as that produced by thermal treatment. The formation of the plate-shaped y phase is explained in terms of a mechanism involving shear on <112> planes of the bcc lattice and the mechanical instability of the g phase.     

Primacy and recency in nonword repetition

An increasing body of evidence suggests that nonword repetition is related to immediate serial memory (e.g., ; ). One possible account of this relationship is that a nonword is processed like a list when it is first encountered. If this is the case, it should be possible to detect serial position effects in repetition of single nonwords. Three experiments tested this prediction. Experiment 1 examined whether there would be syllable serial position primacy and recency effects in repetition of polysyllabic nonwords, and obtained both primacy and recency effects. Experiments 2 and 3 showed that these effects were not due to the controlled duration of the nonwords or the requirements of concurrent articulation or the procedure by which nonwords were created.     

A fixed point theorem for the Weak Kleene valuation scheme

Journal of Philosophical Logic -     

Corporate Social Responsibility,Employee–Company Identification,and Organizational Commitment: Mediation by Employee Engagement

Contrary to the theory and research on employee engagement in the western countries, less consideration has been given to the importance of employee engagement in Asian countries wherein its need is felt more. As more and more companies in Asia realize the importance of a productive workforce, this research examines the mediating role of employee engagement in the relationships of corporate social responsibility (CSR), employee–company identification (E–C) and organizational commitment (OC). Structural analysis of 290 online responses of employees working for various Indian and foreign information technology enabled services (ITES) companies in India, confirms the presence of partial mediation by employee engagement in between its antecedents (CSR and E–C) and its consequence (OC). The proposed model was found to be a good fit. The study provides empirical support to the argument that CSR and E–C are distant antecedents of OC. The results may encourage managers of ITES companies to consider CSR as an investment rather than an expense.