| Pouget, A., Deneve, S., Duhamel, J.-R. A computational perspective on the neural basis of multisensory spatial representation Nature reviews Neuroscience 2002 (3):741-474 [pdf] |
| We argue that current theories of multisensory representations are inconsistent with the existence of a large proportion of multimodal neurons with gain fields and partially shifting receptive fields. Moreover, these theories do not fully resolve the recoding and statistical issues involved in multisensory integration. An alternative theory, which we have recently developed and review here, has important implications for the idea of 'frame of reference' in neural spatial representations. This theory is based on a neural architecture that combines basis functions and attractor dynamics. Basis function units are used to solve the recoding problem, whereas attractor dynamics are used for optimal statistical inferences. This architecture accounts for gain fields and partially shifting receptive fields, which emerge naturally as a result of the network connectivity and dynamics. |
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| Rees, G., Kreiman, G., Koch, C. Neural Correlates of Consciousness in Humans Nature reviews Neuroscience 2002 (3):261-270 [html] |
| The directness and vivid quality of conscious experience belies the complexity of the underlying neural mechanisms, which remain incompletely understood. Recent work has focused on identifying the brain structures and patterns of neural activity within the primate visual system that are correlated with the content of visual consciousness. Functional neuroimaging in humans and electrophysiology in awake mokeys indicate that there are important differences between striate and extrastriate visual cortex in how well neural activity correlates with consciousness. Moreover, recent neuroimaging studies indicate that, in addition to these ventral areas of visual cortex, dorsal prefrontal and parietal areas might contribute to conscious visual experience. |
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| Martinez-Conde, S., Macknik, S.L., Hubel, D.H. The role of fixational eye movements in visual perception Nature reviews Neuroscience 2004 (5):229-240 [pdf] |
| Our eyes continually move even while we fix our gaze on an object. Although these fixational eye movements have a magnitude that should make them visible to us, we are unaware of them. If fixational eye movements are counteracted, our visual perception fades completely as a result of neural adaptation. So, our visual system has a built-in paradox we must fix our gaze to inspect the minute details of our world, but if we were to fixate perfectly, the entire world would fade from view. Owing to their role in counteracting adaptation, fixational eye movements have been studied to elucidate how the brain makes our environment visible. Moreover, because we are not aware of these eye movements, they have been studied to understand the underpinnings of visual awareness. Recent studies of fixational eye movements have focused on determining how visible perception is encoded by neurons in various visual areas of the brain. |
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| Palmeri, T.J., Gauthier, I. Visual object understanding Nature reviews Neuroscience 2004 (5):291-304 [pdf] |
| Visual object understanding includes processes at the nexus of visual perception and visual cognition. A traditional approach separates questions that are more associated with perception how are objects represented by high-level vision from questions that are more associated with cognition how are objects identified, categorized and remembered. However, to understand the bridge between perception and cognition, it is fruitful to abandon any sharp distinction between perceptual and cognitive aspects of visual object understanding. We provide a selective review of research from both the Object Recognition and Perceptual Categorization literatures, highlighting relevant behavioural, neuropsychological, neurophysiological and theoretical research into the representations and processes that underlie visual object understanding in humans and primates. |
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