Abstract not found

Neural correlates of perceptual awareness, until very recently an elusive quarry, are now almost commonplace findings. This article first describes a variety of neural correlates of perceptual awareness based on fMRI, ERPs, and single-unit recordings. It is then argued that our quest should ultimately focus not on mere correlates of awareness, but rather on the neural events that are both necessary and sufficient for perceptual awareness. Indeed, preliminary evidence suggests that although many of the neural correlates already reported may be necessary for the corresponding state of awareness, it is unlikely that they are sufficient for it. The final section considers three hypotheses concerning the possible sufficiency conditions

This paper reviews processing of facial identity and expressions. The issue of independence between or two systems for these tasks has been addressed from different approaches over the past twenty-five years. More recently, neuroimaging techniques have provided researchers with new tools to investigate how facial information is processed in the brain. First, findings from "traditional" approaches to identity and expression processing are summarized. The review then

Neurological syndromes in which consciousness seems to malfunction, such as temporal lobe epilepsy, visual scotomas, Charles Bonnet syndrome, and synesthesia offer valuable clues about the normal functions of consciousness and ‘qualia’. An investigation into these syndromes reveals, we argue, that qualia are different from other brain states in that they possess three functional characteristics, which we state in the form of ‘three laws of qualia ’ based on a loose analogy with Newton’s three laws of classical mechanics. First, they are irrevocable: I cannot simply decide to start seeing the sunset as green, or feel pain as if it were an itch; second, qualia do not always produce the same behaviour: given a set of qualia, we can choose from a potentially infinite set of possible behaviours to execute; and third, qualia endure in short-term memory, as opposed to non-conscious brain states involved in the on-line guidance of behaviour in real time. We suggest that qualia have evolved these and other attributes (e.g. they are ‘filled in’) because of their role in facilitating non-automatic, decision-based action. We also suggest that the apparent epistemic barrier to knowing what qualia another person is experiencing can be overcome simply by using a ‘bridge ’ of neurons; and we offer a hypothesis about the relation between qualia and one’s sense of self.

This paper reviews evidence from neuroscience and quantum computing theory in support of the notion of autonomy in the workings of cognitive processes. De®cits in speech, vision, and motor abilities are described to show how cognitive behavior is not based just on incoming sensory data. Active agents, to which the conscious mind may not have access, are described. Recent developments in quantum computing, of relevance

There is growing evidence that the brain regions involved in encoding an episode are partially reactivated when that episode is later remembered. That is, the process of remembering an episode involves literally returning to the brain state that was present during that episode. This article reviews studies of episodic and associative memory that provide support for the assertion that encoding regions are reactivated during subsequent retrieval. In the first section, studies are reviewed in which neutral stimuli were associated with different modalities of sensory stimuli or different valences of emotional stimuli. When the neutral stimuli were later used as retrieval cues, relevant sensory and emotion processing regions were reactivated. In the second section, studies are reviewed in which participants used different strategies for encoding stimuli. When the stimuli were later retrieved, regions associated with the different encoding strategies were reactivated. Together, these studies demonstrate not only that the encoding experience determines which regions are activated during subsequent retrieval but also that the same regions are activated during encoding and retrieval. In the final section, relevant questions are posed and discussed regarding the reactivation of encoding regions during retrieval.

Genes, synapses and memory storage

Abstract. The sophisticated tools and techniques employed by Nature for purposeful storage of information stand in stark contrast to the primitive and relatively inefficient means used by man. We describe some impressive features of biological data storage, and speculate on approaches to research and development that could benefit the storage industry in the coming decades. Introduction. The storage of information is ubiquitous in our technological society: paper, film, semiconductor memories, audio/video-tapes, magnetic/optical disks, etc., collectively contain many petabytes of information. In contrast, Nature has been frugal in its use of information storage techniques. Blueprints of life, both of plant and of animal, are stored in the DNA molecules. 1-3 Pre-programmed (i.e., instinctive) as well as learned information reside in the

. The great potential offered by Virtual Reality (VR) derives prevalently from the central role, in psychotherapy, occupied by the imagination and by memory. These two elements, which are fundamental in the life of every one of us, present absolute and relative limits to individual potential. Thanks to virtual experiences, it is possible to transcend these limits. The re-created world may at times be more vivid and real than the one that most subjects are able to describe through their own imagination and through their own memory.#This chapter focuses on imaginative techniques to find new ways of applications in therapy. In particular the chapter analyses in which way VR can be used to improve the efficacy of current techniques. VR produces a change with respect to the traditional relationship between client and therapist. The new configuration of this relationship is based on the awareness of being more skilled in the difficult operations of recovery of past experiences, th...

Contents Contact Authors Archives Past issues Instructions for Authors Requirements for Letters Related links About Archives Classified ads Reader Services Search News and Views - April 1999 Transcranial Magnetic Stimulation Applications in Neuropsychiatry Mark S. George, MD; Sarah H. Lisanby, MD; Harold A. Sackeim, PhD In the 1990s, it is difficult to open a newspaper or watch television and not find someone claiming that magnets promote healing. Rarely do these claims stem from double-blind, peer-reviewed studies, making it difficult to separate the wheat from the chaff. The current fads resemble those at the end of the last century, when many were falsely touting the benefits of direct electrical and weak magnetic stimulation. Yet in the midst of this popular interest in magnetic therapy, a new neuroscience field has developed that uses powerful magnetic fields to alter brain activity---transcranial magn