On the theoretical error bound for estimating psychometric functions

The theoretical limits to the amount of error, or the Cramer-Rao bounds, were derived for estimating psychometric functions. These theoretical error bounds were compared with the variability of psychometric functions estimated from human as well as computer-simulated observers. For the simulated observers, due to the limited efficiency of the sampling strategies, including the placement of the signals and the distribution of the trials, the variances of the estimated parameters are seven times the theoretical bound for threshold and 22 times that for slope. For the human observers, the variance is 18 times the theoretical bounds for threshold and 80 times that for slope. Therefore, a major portion of the variances (60% for threshold and 73% for slope) for the human observers is associated with factors other than sampling strategies. Further improvement of the accuracy for estimating psychometric functions will depend on not only optimizing the sampling strategy, but also better understanding the various sources of error related to the behavior of human observers.     

‘Tell us what we need to know to do this!’ Preparing a path to safe uncertainty in assignment writing on a family therapy foundation course

This article describes a single session aimed at helping participants on a family therapy foundation course to move from a position of anxiety and discomfort about completing a written assignment to a position of safe uncertainty. Evaluation from the perspectives of course participants, course facilitators and assignment markers has shown participants engaging more enthusiastically with the writing of the assignment and expressing less anxiety about the process.     

The Ambivalence of Promising Technology

Issues of responsibility in the world of nanotechnology are becoming explicit with the emergence of a discourse on ‘responsible development’ of nanoscience and nanotechnologies. Much of this discourse centres on the ambivalences of nanotechnology and of promising technology in general. Actors must find means of dealing with these ambivalences. Actors’ actions and responses to ambivalence are shaped by their position and context, along with strategic games they are involved in, together with other actors. A number of interviews were conducted with industrial actors with the aim of uncovering their ethical stances towards responsible development of nanotechnology. The data shows that standard repertoires of justification of nanotechnological development were used. Thus, the industrial actors fell back on their position and associated responsibilities. Such responses reinforce a division of moral labour in which industrial actors and scientists can focus on the progress of science and technology, while other actors, such as NGOs, are expected to take care of broader considerations, such as ethical and social issues.     

When Effort is Threatening: The Influence of the Belief in a Just World on Americans' Attitudes Toward Antipoverty Policy

In the political context of the reauthorization of federal welfare reform legislation, a nationally representative sample of 1,570 adults in the United States completed a survey examining the factors that affect attitudes and policy preferences with regard to aid for low-income individuals and families in the United States. This study utilized an innovative survey technique, the factorial survey methodology (Rossi & Nock, 1982), which allows for the simultaneous experimental manipulation of a large number of factors through the use of a vignette. This research demonstrates how the portrayal of difficulties faced by people in need and the ways in which they attempt to overcome these difficulties affect support for policies designed to aid low-income individuals and families. In addition, this study of public attitudes considers the role that psychological orientations of the evaluators play in judgments of families in need. In this case, we examined how the evaluators' belief that the world is a just place influences their evaluations of deservingness. Consistent with our expectations, we found that the more efforts the vignette subject engaged in improving her situation, the less deserving of government benefits she was judged to be by respondents with a strong belief in a just world. The reverse was found among respondents with a weaker belief: more efforts were associated with greater judgments of deservingness.     

Stripes within words affect reading

In a series of eight studies it is shown that the first peak in the horizontal autocorrelation of the image of a word (which captures the similarity in shape between the neighbouring strokes of letters) determines (i) the appearance of the words as striped; (ii) the speed with which the words are read, both aloud and silently; and (iii) the speed with which a paragraph of text can be searched. By subtly distorting the horizontal dimension of text, and thereby reducing the first peak in the horizontal autocorrelation, it is shown that the speed of word recognition can be increased. The increase in speed is greater in poor readers.     

Associations between childhood trauma and emotion-modulated psychophysiological responses to startling sounds: a study of police cadets

Childhood trauma may confer risk for adult psychopathology by altering emotional and physiological responses to subsequent stressors. Few studies have distinguished effects of childhood trauma from effects of current Axis I psychopathology on adult psychophysiological reactivity. The authors exposed 90 psychiatrically healthy police cadets to startling sounds under increasing threat of shock while assessing their eyeblink electromyogram (EMG), skin conductance (SC), and heart rate responses. When compared with those who did not endorse early trauma (n = 65), cadets reporting childhood trauma (n = 25) reported less positive emotion and showed greater SC responses across all threat levels. They also showed threat-dependent elevations in reported negative emotions and EMG responses. Results suggest that childhood trauma may lead to long-lasting alterations in emotional and psychophysiological reactivity even in the absence of current Axis I psychopathology.     

Increased brain serotonin turnover in panic disorder patients in the absence of a panic attack: reduction by a selective serotonin reuptake inhibitor

Since the brain neurotransmitter changes characterising panic disorder remain uncertain, we quantified brain noradrenaline and serotonin turnover in patients with panic disorder, in the absence of a panic attack. Thirty-four untreated patients with panic disorder and 24 matched healthy volunteers were studied. A novel method utilising internal jugular venous sampling, with thermodilution measurement of jugular blood flow, was used to directly quantify brain monoamine turnover, by measuring the overflow of noradrenaline and serotonin metabolites from the brain. Radiographic depiction of brain venous sinuses allowed differential venous sampling from cortical and subcortical regions. The relation of brain serotonin turnover to serotonin transporter genotype and panic disorder severity were evaluated, and the influence of an SSRI drug, citalopram, on serotonin turnover investigated. Brain noradrenaline turnover in panic disorder patients was similar to that in healthy subjects. In contrast, brain serotonin turnover, estimated from jugular venous overflow of the metabolite, 5-hydroxyindole acetic acid, was increased approximately 4-fold in subcortical brain regions and in the cerebral cortex (P < 0.01). Serotonin turnover was highest in patients with the most severe disease, was unrelated to serotonin transporter genotype, and was reduced by citalopram (P < 0.01). Normal brain noradrenaline turnover in panic disorder patients argues against primary importance of the locus coeruleus in this condition. The marked increase in serotonin turnover, in the absence of a panic attack, possibly represents an important underlying neurotransmitter substrate for the disorder, although this point remains uncertain. Support for this interpretation comes from the direct relationship which existed between serotonin turnover and illness severity, and the finding that SSRI administration reduced serotonin turnover. Serotonin transporter genotyping suggested that increased whole brain serotonin turnover most likely derived not from impaired serotonin reuptake, but from increased firing in serotonergic midbrain raphe neurons projecting to both subcortical brain regions and the cerebral cortex.     

Improving access to psychological therapy: Initial evaluation of two UK demonstration sites

Recently the UK Government announced an unprecedented, large-scale initiative for Improving Access to Psychological Therapies (IAPT) for depression and anxiety disorders. Prior to this development, the Department of Health established two pilot projects that aimed to collect valuable information to inform the national roll-out. Doncaster and Newham received additional funds to rapidly increase the availability of CBT-related interventions and to deploy them in new clinical services, operating on stepped-care principles, when appropriate. This article reports an evaluation of the new services (termed ‘demonstration sites’) during their first thirteen months of operation. A session-by-session outcome monitoring system achieved unusually high levels of pre to post-treatment data completeness. Large numbers of patients were treated, with low-intensity interventions (such as guided self-help) being particularly helpful for achieving high throughput. Clinical outcomes were broadly in line with expectation. 55-56% of patients who had attended at least twice (including the assessment interview) were classified as recovered when they left the services and 5% had improved their employment status. Treatment gains were largely maintained at 10 month follow-up. Opening the services to self-referral appeared to facilitate access for some groups that tend to be underrepresented in general practice referrals. Outcomes were comparable for the different ethnic groups who access the services. Issues for the further development of IAPT are discussed.