A tool to act blind? Object-assisted eye-covering as a self-handicapping behavior and social play signal in Balinese long-tailed macaques

Animal Cognition - Self-handicapping behaviors evolved as honest signals that reliably reflect the quality of their performers. In playful activities, self-handicapping is described as...     

UNESCO, genetics, and human rights

In response to a mandate conferred on the International Bioethics Committee (IBC) of UNESCO in November 1993, the IBC has drafted a "universal declaration on the human genome and human rights," which will be considered by the General Conference of UNESCO in November 1997. This article discusses the development of the document and provides the text of the "revised preliminary draft" of the declaration.     

Finger gnosia: a predictor of numerical abilities in children?

This paper aimed to test the specificity of predicting power of finger gnosia on later numerical abilities in school-age children and to contribute to the understanding of this effect. Forty-one children were tested in the beginning of Grade 1 on finger gnosia, left-right orientation (another sign of the Gerstmann "syndrome"), and global development. Fifteen months later, numerical and reading abilities were assessed. Analyses of the results indicated that, contrary to the general measures of cognitive development, performance in the finger gnosia test was a good predictor of numerical skills 1 year later but not of reading skills, which proves the specificity of that predictor. The same conclusion was also true for the left-right orientation. However, finger gnosia could equally predict performance in numerical tasks that do or do not rely heavily on finger representation or on magnitude representation. Results are discussed in terms of the localizationist and the functional hypotheses.     

A sensorimotor account of vision and visual consciousness

Many current neurophysiological, psychophysical, and psychological approaches to vision rest on the idea that when we see, the brain produces an internal representation of the world. The activation of this internal representation is assumed to give rise to the experience of seeing. The problem with this kind of approach is that it leaves unexplained how the existence of such a detailed internal representation might produce visual consciousness. An alternative proposal is made here. We propose that seeing is a way of acting. It is a particular way of exploring the environment. Activity in internal representations does not generate the experience of seeing. The outside world serves as its own, external, representation. The experience of seeing occurs when the organism masters what we call the governing laws of sensorimotor contingency. The advantage of this approach is that it provides a natural and principled way of accounting for visual consciousness, and for the differences in the perceived quality of sensory experience in the different sensory modalities. Several lines of empirical evidence are brought forward in support of the theory, in particular: evidence from experiments in sensorimotor adaptation, visual "filling in," visual stability despite eye movements, change blindness, sensory substitution, and color perception.     

One first? Acquisition of the cardinal and ordinal uses of numbers in preschoolers

We studied the acquisition of the ordinal meaning of number words and examined its development relative to the acquisition of the cardinal meaning. Three groups of 3-, 4-, and 5-year-old children were tested in two tasks requiring the use of number words in both cardinal and ordinal contexts. Understanding of the counting principles was also measured by asking the children to assess the correctness of a cartoon character's counting in both contexts. In general, the children performed cardinal tasks significantly better than ordinal ones. Tasks requiring the production of the number for a given quantity or position were solved more accurately than those testing the ability to select a set of n objects or the object in the nth position. Different profiles were obtained for the principles; those principles shared by the two contexts were mastered earlier in the cardinal context. Regarding order (ir)relevance, older children adhered to rigid ways of counting, producing better results in the ordinal context and incorrect rejections in the cardinal trials. Altogether, our data indicate that the acquisitions of cardinal and ordinal meanings of numbers are related, and cardinality precedes the development of ordinality.     

A Meta-analytic Review of the Role of Child Anxiety Sensitivity in Child Anxiety

Conflicting findings exist regarding (1) whether anxiety sensitivity (AS) is a construct distinct from anxiety in children and (2) the specific nature of the role of AS in child anxiety. This study uses meta-analytic techniques to (1) determine whether youth (ages 6–18 years) have been reported to experience AS, (2) examine whether AS differentiates anxiety disordered youth from youth without diagnoses, and (3) ascertain whether AS distinguishes youth with panic disorder from those with other anxiety disorders. The weighted mean effect size analyses included 15 studies and 6,579 participants. Results suggested positive correlational relationships between AS and anxiety for children (r = 0.26) and adolescents (r = 0.36) and higher levels of AS for anxiety disordered youth than non-clinical youth (d = 0.64). Findings tentatively suggested higher levels of AS for youth with panic disorder than youth diagnosed with other anxiety disorders. Implications and future directions in the research of child AS are discussed.     

Socio-spatial cognition in vervet monkeys

Safety in numbers is thought to be the principal advantage of living in groups for many species. The group can only provide protection against predators, however, when group cohesion is maintained. Vocalisations are used to monitor inter-individual distances, especially under conditions of poor visibility, but should be avoided in the presence of predators. Mentally tracking the movements of silent and invisible group members would allow animals foraging in dense vegetation to stay close to their group members while reducing the use of vocal contact. We tested the socio-spatial cognitive abilities of wild vervet monkeys (Chlorocebus pygerythrus) by comparing their reactions to plausible and implausible displacements of group members simulated by sound playbacks. Our methods are comparable to those used in studies of ‘object permanence’ and ‘invisible displacements’ of inanimate objects. Our results show that vervets can track the whereabouts of invisibly and silently moving group members, at least over short periods of time.     

Symbolic and nonsymbolic number comparison in children with and without dyscalculia

Developmental dyscalculia (DD) is a pervasive difficulty affecting number processing and arithmetic. It is encountered in around 6% of school-aged children. While previous studies have mainly focused on general cognitive functions, the present paper aims to further investigate the hypothesis of a specific numerical deficit in dyscalculia. The performance of 10- and 11-year-old children with DD characterised by a weakness in arithmetic facts retrieval and age-matched control children was compared on various number comparison tasks. Participants were asked to compare a quantity presented in either a symbolic (Arabic numerals, number words, canonical dots patterns) or a nonsymbolic format (noncanonical dots patterns, and random sticks patterns) to the reference quantity 5. DD children showed a greater numerical distance effect than control children, irrespective of the number format. This favours a deficit in the specialised cognitive system underlying the processing of number magnitude in children with DD. Results are discussed in terms of access and representation deficit hypotheses.     

Modern health worries – the dark side of spirituality?

Modern health worries (MHWs) are widespread in modern societies. MHWs were connected to both negative and positive psychological characteristics in previous studies. The study aimed to investigate the relationships among intuitive‐experiential information processing style, spirituality, MHWs, and psychological well‐being. Members of the Hungarian Skeptic Society (N = 128), individuals committed to astrology (N = 601), and people from a non‐representative community sample (N = 554) completed questionnaires assessing intuitive‐experiential information processing style, spirituality, modern health worries (MHWs), and psychological well‐being. Astrologers showed higher levels of spirituality, intuitive‐experiential thinking, and modern health worries than individuals from the community sample; and skeptics scored even lower than the latter group with respect to all three constructs. Within the community sample, medium level connections between measures of spirituality and the experiential thinking style, and weak to medium level correlations between spirituality and MHWs were found. The connection between MHWs and experiential thinking style was completely mediated by spirituality. Individuals with higher levels of spirituality are particularly vulnerable to overgeneralized messages on health related risks. Official communication of potential risks based on rational scientific reasoning is not appropriate to persuade them as it has no impact on the intuitive‐experiential system.