Colour matching of isoluminant samples and backgrounds: a dimming effect

Sequential asymmetrical colour matching of forty Munsell samples simulated under illuminant C and one of eight test illuminants was carried out. The subjects matched the appearance of each sample under illuminant C with its appearance under the test illuminant. Samples and background (N7) were presented for 1 s under the test illuminant and were isoluminant with each other. Subjects adjusted hue, chroma, and value under illuminant C. The experiments distinguished two groups of subjects; some observers needed to reduce the luminance of the sample to make a match while others did not. This 'dimming' occurred when the matches were close to cardinal axes, especially the tritanopic confusion line. A model of luminance and cone-opponent mechanisms contributing to brightness can account for the dimming effect. Details of analysis in cone-opponent space (L - M, L + M - S, L + M) are presented in the companion paper (Stanikunas et al, 2005 Perception 34 this issue).     

Bodies and their parts

How do we think about the space of bodies? Several accounts of mental representations of bodies were addressed in body part verification tasks. Animagery account predicts shorter times to larger parts (e.g., back < hand). Apart distinctiveness account predicts shorter times to more discontinuous parts (e.g., arm < chest). Apart significance account predicts shorter times to parts that are perceptually distinct and functionally important (e.g., head < back). Because distinctiveness and significance are correlated, the latter two accounts are difficult to distinguish. Both name-body and body-body comparisons were investigated in four experiments. In all, larger parts were verified more slowly than smaller ones, eliminating the imagery/size account. Despite the correlation between distinctiveness and significance, the data suggest that when comparisons are perceptual (body-body), part distinctiveness is the best predictor, and when explicit or implicit naming is involved, part significance is the best predictor. Naming seems to activate the functional aspects of bodies.     

Influence of virtual reality training on the roadside crossing judgments of child pedestrians

The roadside crossing judgments of children aged 7, 9, and 11 years were assessed relative to controls before and after training with a computer-simulated traffic environment. Trained children crossed more quickly, and their estimated crossing times became better aligned with actual crossing times. They crossed more promptly, missed fewer safe opportunities to cross, accepted smaller traffic gaps without increasing the number of risky crossings, and showed better conceptual understanding of the factors to be considered when making crossing judgments. All age groups improved to the same extent, and there was no deterioration when children were retested 8 months later. The results are discussed in relation to theoretical arguments concerning the extent to which children's pedestrian judgments are amenable to training.     

Emotional intensity of idiographic sad memories in depression predicts symptom levels 1 year later

When cued with generic happy and sad words, depressed individuals have been found to articulate contextually impoverished memories of autobiographical events. Although this pattern predicts a worse symptomatic course of disorder in some depressed samples, longitudinal findings with the cue-word paradigm are inconsistent. To address the etiological significance of autobiographical memories outside the cue-word paradigm, the authors used an idiographic interview in which depressed participants generated memories of their happiest and saddest lifetime events. Each memory was coded for detail and emotional intensity. At a 1-year follow-up, participants' levels of depressive symptoms were reassessed. Lower emotional intensity of saddest memories predicted higher levels of depressive symptoms at follow-up. Several implications for understanding sadness and emotional disclosure in depression are discussed.     

Self-harmful behaviors in a population-based sample of young adults

A birth cohort of 472 women and 494 men aged 26 years was interviewed about a range of self-harmful behaviors first and then asked about suicidal intent. Lifetime prevalence of self-harm using traditional methods of suicide (ICD [International Classification of Diseases] self-harm) was 13%, with 9% of the sample describing at least one such episode as "attempted suicide." Other self-harmful behaviors were common; 14% of women and 33% of men reported self-battery. ICD self-harm over the past year was reported by 3%, mostly without suicidal intent. ICD self-harm and even lesser behaviors were associated with high odds of reporting suicidal ideation. The findings suggest that studies of self-harm should include behaviors not necessarily associated with suicidal intent.     

The use of imagery in cognitive therapy for psychosis: a case example

There has been a long tradition of studying imagery in relation to psychotic symptoms. Recent studies have suggested that imagery may be involved in the development and maintenance of psychotic symptoms (hallucinations and delusions in particular). Following a review of this literature, including work conducted by the author and colleagues, a case study is used to illustrate the clinical applications of this work. Working with images that were associated with persecutory delusions appeared to contribute to a reduction in distress, preoccupation, and conviction in relation to these beliefs, which were assessed using a standardised measure (PSYRATS). The implications for theory, practice, and future research are considered.     

The development of color categories in two languages: a longitudinal study

This study unites investigations into the linguistic relativity of color categories with research on children's category acquisition. Naming, comprehension, and memory for colors were tracked in 2 populations over a 3-year period. Children from a seminomadic equatorial African culture, whose language contains 5 color terms, were compared with a group of English children. Despite differences in visual environment, language, and education, they showed similar patterns of term acquisition. Both groups acquired color vocabulary slowly and with great individual variation. Those knowing no color terms made recognition errors based on perceptual distance, and the influence of naming on memory increased with age. An initial perceptually driven color continuum appears to be progressively organized into sets appropriate to each culture and language.     

Relational integration, inhibition, and analogical reasoning in older adults

The difficulty of reasoning tasks depends on their relational complexity, which increases with the number of relations that must be considered simultaneously to make an inference, and on the number of irrelevant items that must be inhibited. The authors examined the ability of younger and older adults to integrate multiple relations and inhibit irrelevant stimuli. Young adults performed well at all but the highest level of relational complexity, whereas older adults performed poorly even at a medium level of relational complexity, especially when irrelevant information was presented. Simulations based on a neurocomputational model of analogical reasoning, Learning and Inference with Schemas and Analogies (LISA), suggest that the observed decline in reasoning performance may be explained by a decline in attention and inhibitory functions in older adults.     

Sensory discrimination and intelligence: testing Spearman's other hypothesis

At the centenary of Spearman's seminal 1904 article, his general intelligence hypothesis remains one of the most influential in psychology. Less well known is the article's other hypothesis that there is "a correspondence between what may provisionally be called 'General Discrimination' and 'General Intelligence' which works out with great approximation to one or absoluteness" (Spearman, 1904, p. 284). Studies that do not find high correlations between psychometric intelligence and single sensory discrimination tests do not falsify this hypothesis. This study is the first directly to address Spearman's general intelligence-general sensory discrimination hypothesis. It attempts to replicate his findings with a similar sample of schoolchildren. In a well-fitting structural equation model of the data, general intelligence and general discrimination correlated .92. In a reanalysis of data published byActon and Schroeder (2001), general intelligence and general sensory ability correlated .68 in men and women. One hundred years after its conception, Spearman's other hypothesis achieves some confirmation. The association between general intelligence and general sensory ability remains to be replicated and explained.