The functions of the somatosensory system are multiple. We use tactile input to localize and experience the various qualities of touch, and proprioceptive information to determine the position of different parts of the body with respect to each other, which provides fundamental information for action. Further, tactile exploration of the characteristics of external objects can result in conscious perceptual experience and stimulus or object recognition. Neuroanatomical studies suggest parallel processing as well as serial processing within the cerebral somatosensory system that (...) reflect these separate functions, with one processing stream terminating in the posterior parietal cortex (PPC), and the other terminating in the insula. We suggest that, analogously to the organisation of the visual system, somatosensory processing for the guidance of action can be dissociated from the processing that leads to perception and memory. In addition, we find a second division between tactile information processing about external targets in service of object recognition and tactile information processing related to the body itself. We suggest the posterior parietal cortex subserves both perception and action, whereas the insula principally subserves perceptual recognition and learning. (shrink)

Although the evidence remains tentative at best, the conception of hallucinations in schizophrenia as being underconstrained perception resulting from intrinsic thalamocortical resonance in sensory areas might complement current models of hallucination. However, in itself, the approach falls short of comprehensively explaining the neurogenesis of hallucinations in schizophrenia, as it neglects the role of external attributional biases, mental imagery, and a disconnection between frontal and temporal areas.

Can we learn without consciousness? When the eminent neuropsychologist, Lawrence Weiskrantz first coined the term 'blindsight' to describe a condition whereby a patient could demonstrate that they were aware of some object, yet insist that they were completely unaware of its existence, the response from some in the scientific community was one of extreme skepticism. Even now, there are those who question the existence of unconscious learning, and the topic remains one of the most actively researched and debated in psychology. (...) In recent years evidence for unconscious processing across a range of sensory modalities have come from studies of vision, audition, memory, emotion, and action. Never before have these studies of unconscious processing in the different senses been brought together into a single volume. In a book dedicated to Lawrence Weiskrantz, some of the leading psychologists and cognitive neuroscientists of the day explain what we know about unconscious processing in the different senses. Including contributions from, amongst others, David Milner, Jon Driver, Alan Cowey, and Ray Dolan, the book presents a state of the art account of what we now know about 'the unconscious'. The book will provide a fascinating account for students and researchers in psychology, cognitive neuroscience, and philosophy. (shrink)

Colour has been shown to facilitate the recognition of scene images, but only when these images contain natural scenes, for which colour is ‘diagnostic’. Here we investigate whether colour can also facilitate memory for scene images, and whether this would hold for natural scenes in particular. In the first experiment participants first studied a set of colour and greyscale natural and man-made scene images. Next, the same images were presented, randomly mixed with a different set. Participants were asked to indicate (...) whether they had seen the images during the study phase. Surprisingly, performance was better for greyscale than for coloured images, and this difference is due to the higher false alarm rate for both natural and man-made coloured scenes. We hypothesized that this increase in false alarm rate was due to a shift from scrutinizing details of the image to recognition of the gist of the image. A second experiment, utilizing images without a nameable gist, confirmed this hypothesis as participants now performed equally on greyscale and coloured images. In the final experiment we specifically targeted the more detail-based perception and recognition for greyscale images versus the more gist-based perception and recognition for coloured images with a change detection paradigm. The results show that changes to images are detected faster when image-pairs were presented in greyscale than in colour. This counterintuitive result held for both natural and man-made scenes and thus corroborates the shift from more detailed processing of images in greyscale to more gist-based processing of coloured images. (shrink)

Evolutionary developmental biology (evo-devo) has undergone dramatic transformations since its emergence as a distinct discipline. This paper aims to highlight the scope, power, and future promise of evo-devo to transform and unify diverse aspects of biology. We articulate key questions at the core of eleven biological disciplines—from Evolution, Development, Paleontology, and Neurobiology to Cellular and Molecular Biology, Quantitative Genetics, Human Diseases, Ecology, Agriculture and Science Education, and lastly, Evolutionary Developmental Biology itself—and discuss why evo-devo is uniquely situated to substantially improve (...) our ability to find meaningful answers to these fundamental questions. We posit that the tools, concepts, and ways of thinking developed by evo-devo have profound potential to advance, integrate, and unify biological sciences as well as inform policy decisions and illuminate science education. We look to the next generation of evolutionary developmental biologists to help shape this process as we confront the scientific challenges of the 21st century. (shrink)

No livro Plato’s Philosophers, Catherine Zuckert olha para o Timeu de Platão de maneira renovada e revive implicitamente a tese de A. E. Taylor, segundo a qual Timeu não fala por Platão. Taylor devotou seu escrupuloso comentário de 1927 para construir esse argumento, o qual, porém, encalhou diante da questão colocada dez anos depois por F. M. Cornford, no livro Plato’s Cosmology : “Qual poderia ter sido o seu motivo?” O motivo de Platão era tanto pedagógico quanto parmenídico: assim como (...) a deusa expõe o peregrino à “Via da Opinião” depois da revelação da “Verdade”, assim também o Timeu de Platão expõe o leitor a um relato poético de uma cosmologia baseada na visão – outro kosmo/j e0pe/wn a0pathlo/j – depois da revelação, feita na República V-VII, da ontologia platônica puramente inteligível. (shrink)

Celebrando o papel de Newton da Costa na história da paraconsistência, este trabalho examina o uso e abuso da deliberada auto-contradição. Iniciado por Parmênides, desenvolvido por Platão, e continuado por Cícero, uma antiga tradição filosófica usava deliberadamente discursos paraconsistentes para revelar a verdade. Nos tempos modernos, o decisionismo tem usado uma deliberada auto-contradição contra a revelação Judaico-Cristã. DOI:10.5007/1808-1711.2010v14n1p1.