| Blakemore, S.J., Wolpert, D.M., Frith, C.D. Abnormalities in the awareness of action Trends in Cognitive Sciences 2002 (6)6:237-242 [pdf] |
| Optimal motor control relies on internal representations of the actual, desired and predicted states of our limbs and the external world. Only certain components of these internal representations are available to awareness. We suggest that impairments of the components of internal representations might underlie a broad variety of neuropsychiatric symptoms, including the anarchic hand sign, phantom limbs, utilization behaviour and delusions of control. |
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| Clark, A. An embodied cognitive science? Trends in Cognitive Sciences 1999 (3)9:345-351 [html] |
| The last ten years have seen an increasing interest, within cognitive science, in issues concerning the physical body, the local environment, and the complex interplay between neural systems and the wider world in which they function. Yet many unanswered questions remain, and the shape of a genuinely physically embodied, environmentally embedded science of the mind is still unclear. In this article I will raise a number of critical questions concerning the nature and scope of this approach, drawing a distinction between two kinds of appeal to embodiment: (1) 'Simple' cases, in which bodily and environmental properties merely constrain accounts that retain the focus on inner organization and processing; and (2) More radical appeals, in which attention to bodily and environmental features is meant to transform both the subject matter and the theoretical framework of cognitive science. |
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| Foster, D.H. Does colour constancy exist? Trends in Cognitive Sciences 2003 (7)10:439-443 [html] |
| For a stable visual world, the colours of objects should appear the same under different lights. This property of colour constancy has been assumed to be fundamental to vision, and many experimental attempts have been made to quantify it. I contend here, however, that the usual methods of measurement are either too coarse or concentrate not on colour constancy itself, but on other, complementary aspects of scene perception. Whether colour constancy exists other than in nominal terms remains unclear. |
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| Gallese, V., Goldman, A. Mirror neurons and the simulation theory of mind-reading Trends in Cognitive Sciences 1998 (2)12 [pdf] |
| A new class of visuomotor neuron has been recently discovered in the monkey s premotor cortex: mirror neurons. These neurons respond both when a particular action is performed by the recorded monkey and when the same action, performed by another individual, is observed. Mirror neurons appear to form a cortical system matching observation and execution of goal-related motor actions. Experimental evidence suggests that a similar matching system also exists in humans. What might be the functional role of this matching system? One possible function is to enable an organism to detect certain mental states of observed conspecifics. This function might be part of, or a precursor to, a more general mind-reading ability. Two different accounts of mindreading have been suggested. According to theory theory , mental states are represented as inferred posits of a naive theory. According to simulation theory , other people s mental states are represented by adopting their perspective: by tracking or matching their states with resonant states of one s own. The activity of mirror neurons, and the fact that observers undergo motor facilitation in the same muscular groups as those utilized by target agents, are findings that accord well with simulation theory but would not be predicted by theory theory. |
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| Leopold, D.A., Logothetis, N.K. Multistable phenomena: changing views in perception Trends in Cognitive Sciences 1999 (3)7 [pdf] |
| Traditional explanations of multistable visual phenomena (e.g. ambiguous figures, perceptual rivalry) suggest that the basis for spontaneous reversals in perception lies in antagonistic connectivity within the visual system. In this review, we suggest an alternative, albeit speculative, explanation for visual multistability that spontaneous alternations reflect responses to active, programmed events initiated by brain areas that integrate sensory and non-sensory information to coordinate a diversity of behaviors. Much evidence suggests that perceptual reversals are themselves more closely related to the expression of a behavior than to passive sensory responses: (1) they are initiated spontaneously, often voluntarily, and are influenced by subjective variables such as attention and mood; (2) the alternation process is greatly facilitated with practice and compromised by lesions in non-visual cortical areas; (3) the alternation process has temporal dynamics similar to those of spontaneously initiated behaviors; (4) functional imaging reveals that brain areas associated with a variety of cognitive behaviors are specifically activated when vision becomes unstable. In this scheme, reorganizations of activity throughout the visual cortex, concurrent with perceptual reversals, are initiated by higher, largely non-sensory brain centers. Such direct intervention in the processing of the sensory input by brain structures associated with planning and motor programming might serve an important role in perceptual organization, particularly in aspects related to selective attention. |
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| MacLeod, D.I. New dimension in color perception Trends in Cognitive Sciences 2003 (7)3:97-99 [html] |
| Colors are generally ordered in three dimensions, with hue and saturation as polar coordinates of a color circle, and brightness as the third dimension. Intuitively, lines of constant hue (but variable saturation) in such a color space should converge on an achromatic point devoid of hue. However, in new experiments by Ekroll et al. using colored patches in colored surrounds, constant hue lines converge not on 'gray' but on the surround color. This paradoxical observation suggests that the standard three-dimensional conception of perceived color is inadequate. |
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| Thompson, E., Varela, F.J. Radical embodiment: neural dynamics and cosnciousness Trends in Cognitive Sciences 2001 (5)10:418-425 [pdf] |
| Manifeste de la position 'enactive': la conscience n'est pas basé sur les épiphénomènes que sont les NCC, mais sur des interactions dynamiques de grande échelles, avec une causalité montante et descendante vis-à-vis des propriétés émergentes du système. D'autre part, critique de la position internaliste: le système dynamique implique le corps et l'environnement et il n'est pas donné que le decoupage en sous-système ne doivent pas se faire au travers de ces frontières plutot que selon ces frontières. |
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| Pylyshyn, Z. Return of the mental image: are there really pictures in the brain? Trends in Cognitive Sciences 2003 (7)3:113-118 [pdf] |
| In the past decade there has been renewed interest in the study of mental imagery. Emboldened by new findings from neuroscience, many people have revived the idea that mental imagery involves a special format of thought, one that is pictorial in nature. But the evidence and the arguments that exposed deep conceptual and empirical problems in the picture theory over the past 300 years have not gone away. I argue that the new evidence from neural imaging and clinical neuropsychology does little to justify this recidivism because it does not address the format of mental images. I also discuss some reasons why the picture theory is so resistant to counterarguments and suggest ways in which non-pictorial theories might account for the apparent spatial nature of images. |
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| Wegner, D.M. The mind's best trick: how we experience conscious will Trends in Cognitive Sciences 2003 (7)2:65-69 [pdf] |
| We often experience consciously willing our actions. This experience is so profound that it tempts us to believe that our actions are caused by consciousness. It could also be a trick, however the mind s way of estimating its own apparent authorship by drawing causal inferences about relationships between thoughts and actions. Cognitive, social, and neuropsychological studies of apparent mental causation suggest that experiences of conscious will frequently depart from actual causal processes and so may not reflect direct perceptions of conscious thought causing action. |
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| Feldman, J. What is a visual object ? Trends in Cognitive Sciences 2003 (7)6:252-256 [pdf] |
| The concept of an object plays a central role in cognitive science, particularly in vision, reasoning and conceptual development but it has rarely been given a concrete formal definition. Here I argue that visual objects cannot be defined according to simple physical properties but can instead be understood in terms of the hierarchical organization of visual scene interpretations. Within the tree describing such a hierarchical description, certain nodes make natural candidates as the joints between objects, representing division points between parts of the image that cohere internally but do not perceptually group with one another. Thus each subtree hanging from such a node corresponds to a single perceived object . This formal defi- nition accords with several intuitions about the way objects behave. |
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| Blakemore, S.J., Wolpert, D.M., Frith, C.D. Abnormalities in the awareness of action Trends in Cognitive Sciences 2002 (6)6:237-242 |
| Clark, A. An embodied cognitive science? Trends in Cognitive Sciences 1999 (3)9:345-351 |
| Blackmore, S. Crossing the chasm of consciousness Trends in Cognitive Sciences 2002 (6)7 |
| Foster, D.H. Does colour constancy exist? Trends in Cognitive Sciences 2003 (7)10:439-443 |
| Gallese, V., Goldman, A. Mirror neurons and the simulation theory of mind-reading Trends in Cognitive Sciences 1998 (2)12 |
| Leopold, D.A., Logothetis, N.K. Multistable phenomena: changing views in perception Trends in Cognitive Sciences 1999 (3)7 |
| MacLeod, D.I. New dimension in color perception Trends in Cognitive Sciences 2003 (7)3:97-99 |
| Wolpert, D.M., Ghahramani, Z., Flanagan, J.R. Perspectives and Problems in Motor Learning Trends in Cognitive Sciences 2001 (5)11:487-494 |
| Thompson, E., Varela, F.J. Radical embodiment: neural dynamics and cosnciousness Trends in Cognitive Sciences 2001 (5)10:418-425 |
| Pylyshyn, Z. Return of the mental image: are there really pictures in the brain? Trends in Cognitive Sciences 2003 (7)3:113-118 |
| Wegner, D.M. The mind's best trick: how we experience conscious will Trends in Cognitive Sciences 2003 (7)2:65-69 |
| Feldman, J. What is a visual object ? Trends in Cognitive Sciences 2003 (7)6:252-256 |