The relationship between search efficiency and crowding

The role of target salience in crowding has remained controversial largely because salience usually escapes objective measurement. Here we address this problem using search efficiency as a measure of target salience. In separate experiments observers determined whether parafoveal arrays of vertical Gabor patterns contained targets having a unique colour, a unique direction of motion, and a unique temporal frequency. We analysed search efficiency in the conventional manner using reaction-time gradients (in seconds per item). We also considered accuracy gradients (in percent-correct per item). Crowding is typically quantified by comparing the acuity for a target within an array to the acuity for a target presented alone. We measured orientation acuity for determining whether a slightly tilted target was clockwise or anticlockwise of vertical. Targets with a unique colour or direction of motion were found to pop out, ie (with one exception) reaction-time and accuracy gradients were insignificantly different from zero. Acuity for these targets was significantly greater than acuity for targets whose neighbours had the same colour and direction of motion. Manipulation of temporal frequency produced a wide range of search efficiencies. For three of four observers we found a linear relationship between acuity and the accuracy gradient, shallow gradients being associated with high acuity. In general, we find that crowding is weakened when observers can find a parafoveally presented target quickly and accurately.     

The interpersonal effects of emotions in negotiations: a motivated information processing approach

Three experiments tested a motivated information processing account of the interpersonal effects of anger and happiness in negotiations. In Experiment 1, participants received information about the opponent's emotion (anger, happiness, or none) in a computer-mediated negotiation. As predicted, they conceded more to an angry opponent than to a happy one (controls falling in between), but only when they had a low (rather than a high) need for cognitive closure. Experiment 2 similarly showed that participants were only affected by the other's emotion under low rather than high time pressure, because time pressure reduced their degree of information processing. Finally, Experiment 3 showed that negotiators were only influenced by their opponent's emotion if they had low (rather than high) power. These results support the motivated information processing model by showing that negotiators are only affected by their opponent's emotions if they are motivated to consider them.     

Force matching errors following eccentric exercise

During eccentric exercise contracting muscles are forcibly lengthened, to act as a brake to control motion of the body. A consequence of eccentric exercise is damage to muscle fibres. It has been reported that following the damage there is disturbance to proprioception, in particular, the senses of force and limb position. Force sense was tested in an isometric force-matching task using the elbow flexor muscles of both arms before and after the muscles in one arm had performed 50 eccentric contractions at a strength of 30% of a maximum voluntary contraction (MVC). The exercise led to an immediate reduction of about 40%, in the force generated during an MVC followed by a slow recovery over the next four days, and to the development of delayed onset muscle soreness (DOMS) lasting about the same time. After the exercise, even though participants believed they were making an accurate match, they made large matching errors, in a direction where the exercised arm developed less force than the unexercised arm. This was true whichever arm was used to generate the reference forces, which were in a range of 5-30% of the reference arm's MVC, with visual feedback of the reference arm's force levels provided to the participant. The errors were correlated with the fall in MVC following the exercise, suggesting that participants were not matching force, but the subjective effort needed to generate the force: the same effort producing less force in a muscle weakened by eccentric exercise. The errors were, however, larger than predicted from the measured reduction in MVC, suggesting that factors other than effort might also be contributing. One factor may be DOMS. To test this idea, force matches were done in the presence of pain, induced in unexercised muscles by injection of hypertonic (5%) saline or by the application of noxious heat to the skin over the muscle. Both procedures led to errors in the same direction as those seen after eccentric exercise.     

Psychometric properties of the social phobia inventory: further evaluation

This study investigated the psychometric properties of the Social Phobia Inventory [SPIN; Connor, K. M., Davidson, J. R. T., Churchill, L. E., Sherwood, A., Foa, E., Wesler, R.H., 2000. Psychometric properties of the Social Phobia Inventory (SPIN). British Journal of Psychiatry, 176, 379-386], a measure of severity in social phobia (social anxiety disorder). Participants included 132 participants with social phobia, 57 participants with panic disorder and agoraphobia (PDA), and 62 participants with obsessive-compulsive disorder (OCD). Confirming findings from an initial validation study, the SPIN was found to have excellent internal consistency and good test-retest reliability. It also distinguished well between those with social phobia and those with either PDA or OCD. Good convergent and discriminant validity were established by examining correlations with other conceptually related and unrelated scales. Finally, the SPIN was sensitive to changes in social phobia severity following cognitive behavioral group treatment. In conclusion, the SPIN is both reliable and valid for the measurement of social phobia severity and outcome following psychological treatment.     

Forced-choice assessments of personality for selection: evaluating issues of normative assessment and faking resistance

Recent research suggests multidimensional forced-choice (MFC) response formats may provide resistance to purposeful response distortion on personality assessments. It remains unclear, however, whether these formats provide normative trait information required for selection contexts. The current research evaluated score correspondences between an MFC format measure and 2 Likert-type measures in honest and instructed-faking conditions. In honest response conditions, scores from the MFC measure appeared valid indicators of normative trait standing. Under faking conditions, the MFC measure showed less score inflation than the Likert measure at the group level of analysis. In the individual-level analyses, however, the MFC measure was as affected by faking as was the Likert measure. Results suggest the MFC format is not a viable method to control faking.     

Syllable monitoring in internally and externally generated English words

The ability of English speakers to monitor internally and externally generated words for syllables was investigated in this paper. An internal speech monitoring task required participants to silently generate a carrier word on hearing a semantically related prompt word (e.g., reveal—divulge). These productions were monitored for prespecified target strings that were either a syllable match (e.g., /dai/), a syllable mismatch (e.g., /daiv/), or unrelated (e.g., /hju:/) to the initial syllable of the word. In all three experiments the longer target sequence was monitored for faster. However, this tendency reached significance only when the longer string also matched a syllable in the carrier word. External speech versions of each experiment were run that yielded a similar influence of syllabicity but only when the syllable match string also had a closed structure. It was concluded that any influence of syllabicity found using either task reflected the properties of a shared perception-based monitoring system.     

Restraint stress and corticotropin releasing hormone modulation of murine cutaneous POMC mRNA

The skin is a unique immunological defense barrier that protects the organism from occupational and environmental exposures and provides a model system in which to evaluate the interaction of the central nervous system with the peripheral immune response. In the studies presented here, we tested mild, acute restraint stress activation of the cutaneous corticotropin releasing hormone-pro-opiomelanocortin (CRH-POMC) axis. We verified that 2 h restraint stress increased the serum concentration of corticosterone and alpha-melanocyte stimulating hormone. We report for the first time that CRH upregulates POMC mRNA expression in mouse skin in vitro. We also demonstrated, by RT-PCR, that 2,4 di-nitrofluorobenzene (DNFB) upregulates cutaneous POMC mRNA expression, the production of which is suppressed by restraint stress. These data confirm the presence and functionality of two hormones of the hypothalamo-pituitary axis in the skin and suggest that activation of the central hypothalamo-pituitary-adrenal axis may over ride activation of the cutaneous CRH-POMC mechanism in the development of DNFB-stimulated allergic contact dermatitis.     

The relative importance of three domains of positive and negative social exchanges: a longitudinal model with comparable measures

Researchers have expressed considerable interest in the question of whether positive or negative social exchanges more strongly affect psychological health, but previous studies have been limited by using nonparallel measures of positive and negative social exchanges, by measuring negative affect only, and by relying largely on cross-sectional designs. The independent effects of positive and negative exchanges on both positive and negative affect were examined in a short-term longitudinal study of 277 older adults, using social exchange measures with parallel content and equivalent reliability and validity. In cross-sectional analyses, positive exchanges predicted positive affect, and negative exchanges predicted negative affect. In longitudinal analyses, however, negative exchanges predicted both positive and negative affect, whereas positive exchanges were unrelated to either outcome. The more potent and longer-lasting effects of negative exchanges have important implications for theory and interventions.     

Angioedema and maculopapular eruptions associated with carbamazepine administration

Cutaneous rashes and eruptions can be caused by many medications, including carbamazepine. The presentation can be varied depending on severity. Cutaneous eruptions occur in 3% of individuals administered carbamazepine. Angioedema, a rare side effect of carbamazepine, involves vascular leakage in dermis and subcutis mediated by immunoglobulin E and/or bradykinins. Angioedema is more common in females and in the third decade of life. We report the case of a 27-year-old Indian woman who developed maculopapular rash and angioedema secondary to carbamazepine administration. The patient responded successfully to withdrawal of the drug and treatment with antihistamines. Due to the potentially life-threatening complications of this condition and the increasing use of anticonvulsants in the treatment of mood disorders, psychiatrists must be aware of the diagnosis and treatment of this condition.