How long to get to the “gist” of real-world natural scenes?

This study aimed at assessing the processing time of a natural scene in a fast categorization task of its context or “gist”. In Experiment 1, human subjects performed 4 go/no-go categorization tasks in succession with colour pictures of real-world scenes belonging to 2 natural categories: “Sea” and “mountain”, and 2 artificial categories: “Indoor” and “urban”. Experiment 2 used colour and grey-level scenes in the same tasks to assess the role of colour cues on performance. Pictures were flashed for 26 ms. Both experiments showed that the gist of real-world scenes can be extracted with high accuracy (>90%), short median RT (400-460 ms) and early responses triggered with latencies as short as 260-300 ms. Natural scenes were processed faster than artificial scenes. Categories for which colour could have a diagnostic value were processed faster in colour than in grey. Finally, processing speed is compared for scene and object categorization tasks.     

Have sex differences in spatial ability evolved from male competition for mating and female concern for survival?

Drawing on the theoretical and empirical foundations of two evolutionary models, we argue that, among humans and other mammals, a twofold selection process would parsimoniously account for sex-linked advantages in spatial contexts. In males, a superiority for both solving navigation-related spatial problems and understanding physical principles that apply to the behavior of projectiles could have been inherited from mating-oriented male competition involving extensive ranging and agonistic displays. In females, a form of superior spatial memory may have been shaped in relation to a costly reproduction system compelling them to safeguard their survival and that of their offspring by fostering low-risk strategies consisting of restricted navigation as well as concentration on nearby spatial cues. Based on the combined action of competition and survival pressures, we submit new predictions as to spatial sex differences in several species including humans.     

Spatial ability and home-range size: examining the relationship in Western men and women (Homo sapiens)

In mammals, spatial sex differences may have coevolved with sex differences in the size of home ranges. This study first evaluated whether, in keeping with most mammals and traditional human (Homo sapiens) societies, home ranges are larger in male than in female Westerners. Second, it established whether navigation patterns are associated with a broader set of spatial abilities in men than in women. Results showed that current male home ranges surpass female home ranges. Ranging was also positively correlated with achievement in tests of mental rotation, surface development, and location memory among men only, whereas it was associated with embedded figures scores in both sexes. Overall, these findings substantiate the adaptive role of several spatial sex differences in humans.     

A Norwegian adaptation of the Penn State Worry Questionnaire: factor structure, reliability, validity and norms

A Norwegian version of the Penn State Worry Questionnaire (PSWQ) was administered to 304 undergraduate students together with the Beck Depression Inventory (BDI), the State-Trait Anxiety Inventory (STAI) and the Maudsley Obsessive Compulsive Inventory (MOCI). The PSWQ was also administered to a community sample comprising 879 subjects, together with the Beck Anxiety Inventory (BAI), the Beck Depression Inventory II (BDI II) and the White Bear Suppression Inventory (WBSI). Structural equation modeling showed that a three-factor solution of the PSWQ gave the best goodness of fit. The Norwegian version of the PSWQ demonstrated adequate psychometric properties in terms of reliability and validity in both samples. Females scored higher than males on PSWQ.     

Effects of classification context on categorization in natural categories

The patterns of classification of borderline instances of eight common taxonomic categories were examined under three different instructional conditions to test two predictions: first, that lack of a specified context contributes to vagueness in categorization, and second, that altering the purpose of classification can lead to greater or lesser dependence on similarity in classification. The instructional conditions contrasted purely pragmatic with more technical/quasi-legal contexts as purposes for classification, and these were compared with a no-context control. The measures of category vagueness were between-subjects disagreement and within-subjects consistency, and the measures of similarity-based categorization were category breadth and the correlation of instance categorization probability with mean rated typicality, independently measured in a neutral context. Contrary to predictions, none of the measures of vagueness, reliability, category breadth, or correlation with typicality were generally affected by the instructional setting as a function of pragmatic versus technical purposes. Only one subcondition, in which a situational context was implied in addition to a purposive context, produced a significant change in categorization. Further experiments demonstrated that the effect of context was not increased when participants talked their way through the task, and that a technical context did not elicit more all-or-none categorization than did a pragmatic context. These findings place an important boundary condition on the effects of instructional context on conceptual categorization.     

Mathematics learning disability in girls with Turner syndrome or fragile X syndrome

Two studies were carried out to examine the persistence (Study 1) and characteristics (Study 2) of mathematics learning disability (MLD) in girls with Turner syndrome or fragile X during the primary school years (ages 5-9 years). In Study 1, the rate of MLD for each syndrome group exceeded the rate observed in a grade-matched comparison group, although the likelihood of MLD persisting through the primary school years was comparable for all three groups. In Study 2, formal and informal math skills were compared across the syndrome groups, a normative group, and children from the normative group who had MLD. Few differences were observed between the Turner syndrome and normative groups. Despite having rote counting and number representation skills comparable to those in the normative group, girls with fragile X had difficulty with counting rules (e.g., cardinality, number constancy). However, this difficulty did not distingush them from the MLD group. Overall, counting skills appear to distinguish the Turner syndrome and fragile X groups, suggesting that the specificity of math deficits emerges earlier for fragile X than Turner syndrome.     

Visuospatial skills and their association with math performance in girls with fragile X or Turner syndrome.

The present study was designed to assess object identification ("what") and location ("where") skills among girls with fragile X or Turner syndrome and girls with neither disorder. Participants completed standardized subtests of visual perception and tasks of visuospatial "what" and "where" memory. Girls with fragile X had average performance on most object identification tasks, yet 53% failed to accurately recreate the gestalt of a design during the "where" memory task. Fewer than 7% of girls in the Turner or comparison group made this error. Girls with Turner syndrome had lower scores and longer response times on object perception tasks and had poorer recall of location for internal features of the design on the "where" memory task, relative to girls in the comparison or fragile X group. When limiting analyses to IQ-matched samples, correlations between math and visual perception tasks emerged, but only for girls with fragile X. These results reflect important differences between two cognitive phenotypes and have implications for the role of visuospatial processing in early math performance.     

How long does it take to find a cause? An online investigation of implicit causality in sentence production

Some interpersonal verbs show an implicit causality bias in favour of their subject or their object. Such a bias is generally seen in offline continuation tasks where participants are required to finish a fragment containing the verb (e.g., Peter annoyed Jane because ...). The implicit causality bias has been ascribed to the subject's focusing on the initiator of the event denoted by the verb. According to this "focusing theory" the implicit cause has a higher level of activation, at least after the connective "because" has been read. Recently, the focusing theory has been criticized by researchers who used a probe recognition or reading-time methodology. However no clear alternative has been proposed to explain the offline continuation data. In this paper, we report three experiments using an online continuation task, which showed that subjects took more time to imagine an ending when the fragment to be completed contained an anaphor that was incongruent with the verbal bias (e.g., Peter annoyed Jane because she ...). This result suggests that the offline continuation data could reflect the cognitive effort associated with finding a predicate with an agent incongruent with the implicit causality bias of a verb. In the discussion, we suggest that this effort could be related to the number of constraints that an incongruent clause must satisfy to be consistent with the causal structure of the discourse.     

Limits to doubt

Supported by Ian Hacking’s concept of “intervention,” and Charles Taylor’s concept of “intentionality,” this article argues that doubting is acting, and that doubting is therefore subject to the same demands of responsibility as any other action. The argument is developed by using medical practice as a test-case. The central suggestion is that the demand of acting responsibly limits doubt in medicine. The article focuses on two such limitations to doubt. Firstly, the article argues that it is irresponsible to doubt that our actions can harm other people. Secondly, the article argues that it is irresponsible not to strive for coherence between our utterances of doubt and our other actions. Incoherence here can cause “cultural impoverishment.” In a larger context this article also argues that medicine can enrich our epistemology, because medical knowledge displays important traits of knowledge that are downplayed in traditional epistemology derived from mathematics and physics. In particular, medicine makes it possible to get the relation between ethics and epistemology into sharper focus. The endpoint in medical epistemology is “responsible action,” and not certainty in and of itself.     

Bright light treatment has limited effect in subjects over 55 years with mild early morning awakening

31 subjects, age 55 yr. or older, suffering from mild early morning awakening were randomized to either a bright light (10,000 lux) or to a red dim light placebo condition (200 lux). Light exposure took place in the evening in the patients' homes, 60 to 30 min. before bedtime and lasted for 3 wk. The subjects kept a sleep diary for 2 wk. and wore an actigraph for 1 wk. both before treatment and at post-treatment. Of the eight sleep diary outcome variables, significant effects that could be attributed to the light treatment were only detected for time spent in bed after final morning awakening. None of the six actigraph outcome variables yielded any significant effect of the light therapy. Explanations for the limited therapeutic effects of bright light treatment obtained in the present study are discussed, such as the criteria defining early morning awakening, the selection procedure, problems with compliance, age of the sample, and the dose of light. The lack of an objective circadian marker in this study could represent a problem concerning the timing of the light exposure. Despite the limited success of bright light therapy in this study, bright light therapy should still be considered as a treatment option for early morning awakening.