Research digest: post-traumatic stress disorder

The onset of weaning is often described as an important early milestone, but it creates considerable emotional turbulence in the motherinfant relationship. The interruption of the breast-feeding relationship, whether gradual or sudden, creates a very special kind of agony for both the mother and baby, especially when a good trusting relationship with the breast has been found. This paper explores some of the hurts and sacrifices made on both sides during weaning, and looks at some of the subtle reactions to mutual feelings of rejection at this time. It also describes some of the difficulties that arise when the work of weaning is compromised by certain anxieties in the feeding relationship. Extracts from several psychoanalytical infant observations are used both to illustrate and to discuss these themes.     

Inhibition and the right inferior frontal cortex

It is controversial whether different cognitive functions can be mapped to discrete regions of the prefrontal cortex (PFC). The localisationist tradition has associated one cognitive function - inhibition - by turns with dorsolateral prefrontal cortex (DLPFC), inferior frontal cortex (IFC), or orbital frontal cortex (OFC). Inhibition is postulated to be a mechanism by which PFC exerts its effects on subcortical and posterior-cortical regions to implement executive control. We review evidence concerning inhibition of responses and task-sets. Whereas neuroimaging implicates diverse PFC foci, advances in human lesion-mapping support the functional localization of such inhibition to right IFC alone. Future research should investigate the generality of this proposed inhibitory function to other task domains, and its interaction within a wider network.     

Sales Force Motivation Using Travel Incentives: Some Empirical Evidence

This study examines the use of travel incentives as motivators for a commission only life insurance sales force in the United Kingdom. A sample of 1,083 sales representatives reported that travel is a strong motivator and valued more highly than several other types of incentives.     

The state,the institution,and the patient: A three-way collison at the crossroads as a hospital fights closure

This paper recounts the story of a National Health Service hospital which was almost closed for financial reasons in 1990. After a political campaign carried out in the full glare of publicity, the Hospital was reprieved. The account is based on the author's conversations with members of staff. The story of the staff, the patients, the Hospital, and the political struggle are woven together by common themes which are highlighted by reference to the Oedipus myth.     

Mandarin speech perception by ear and eye follows a universal principle

In this study, the nature of speech perception of native Mandarin Chinese was compared with that of American English speakers, using synthetic visual and auditory continua (from /ba/ to /da/) in an expanded factorial design. In Experiment 1, speakers identified synthetic unimodal and bimodal speech syllables as either /ba/ or /da/. In Experiment 2, Mandarin speakers were given nine possible response alternatives. Syllable identification was influenced by both visual and auditory sources of information for both Mandarin and English speakers. Performance was better described by the fuzzy logical model of perception than by an auditory dominance model or a weighted-averaging model. Overall, the results are consistent with the idea that although there may be differences in information (which reflect differences in phonemic repertoires, phonetic realizations of the syllables, and the phonotactic constraints of languages), the underlying nature of audiovisual speech processing is similar across languages.     

Reduced discriminability following perceptual learning with odours

In this experiment, the effects of prior experience on odour perception and discrimination were explored. Participants repeatedly sniffed a mixture composed of two odours, AX, as well as smelling two further odours alone, B and Y. After this training phase, participants were asked to rate the similarity of the odours A and X, B and Y, and a non-exposed pair C and Z. A and X were judged as significantly more alike than the other pairs. Exactly the same pattern emerged on a second test, in which participants were asked to select the odd odour out of sets of three. It was consistently harder for participants to pick the odd odour when the stimuli were drawn from the AX pair (eg A versus AX versus AX). Not only do these findings demonstrate that prior experience can affect odour perception, a finding not predicted by theories of odour perception based solely upon the physiochemical properties of odours, they also suggest that experience can act to selectively decrease discriminability.     

The effectiveness of drug treatment programs in reducing criminal behavior: a meta-analysis

The main aim of this paper is to assess the effectiveness of drug treatment programs in reducing criminal behavior. The research is based on a systematic review and meta-analysis of evaluations of drug treatment programs. The research investigated various drug treatment programs including methadone treatment, therapeutic communities, post-release supervision for drug-misusing offenders, and drug courts, and focused on drug treatment programs that were primarily concerned with heroin, crack and cocaine misuse. The main outcome variable analyzed was reoffending following treatment as measured by self-reports or official records. The study was based on a meta-analysis of 28 evaluations of drug treatment programs. The meta-analysis involved calculating individual effect sizes for each study and weighted mean effect sizes for groups of studies. The mean odds of offending following treatment were significantly lower among clients of the drug treatment programs than among the comparison groups. However, the results varied by type of program, type of evaluation methods used, and characteristics of clients.     

Task and sex modulate the brain response to emotional incongruity in Asian listeners

In order to recognize banter or sarcasm in social interactions, listeners must integrate verbal and vocal emotional expressions. Here, we investigated event-related potential correlates of this integration in Asian listeners. We presented emotional words spoken with congruous or incongruous emotional prosody. When listeners classified word meaning as positive or negative and ignored prosody, incongruous trials elicited a larger late positivity than congruous trials in women but not in men. Sex differences were absent when listeners evaluated the congruence between word meaning and emotional prosody. The similarity of these results to those obtained in Western listeners suggests that sex differences in emotional speech processing depend on attentional focus and may reflect culturally independent mechanisms.     

Olfactory imagery: A review

Olfactions unique cognitive architecture, the apparently inconsistent evidence favoring imagery, and its difficulty of evocation have led some to conclude that there is no capacity for olfactory imagery. Using three streams of evidence, we examine the validity of this claim. First, self-reports of olfactory imagery can resemble those obtained for actual perception. Second, imagining an odor can produce effects similar to actual perception. Third, olfactory perception and memory-based images can interact. A model of olfactory imagery is then presented that utilizes the same systems employed in actual perception, with similar constraints. This model is consistent with olfactions unique information-processing capacities and can account for previous experimental inconsistencies on the basis of difficulty of evocation, a consequence of unstable access to semantic information. In sum, the evidence presented here is favorable to the existence of an olfactory imagery capacity.     

The implications of linking the dynamic performance and turnover literatures

This article examines how the literatures of dynamic performance and the performance-turnover relationship inform each other. The nonrandom performance turnover relationship suggests that dynamic performance studies may be biased by their elimination of participants who do not remain for the entire study period. The authors demonstrated that the performance slopes of those who leave an organization differ from the performance slopes of those who remain. This finding suggests that studies of the performance-turnover relationship need to consider employee performance trends when predicting turnover. Replicating and extending the research of D. A. Harrison, M. Virick, and S. William (1996), the authors found that performance changes from the previous month and performance trends measured over a longer time period explained variance in voluntary turnover beyond current performance. Finally, the authors showed that performance trends interacted with current performance in the prediction of voluntary turnover.