A source of despair in consciousness studies is the way in which popular science writers continue to plough ahead making pronouncements that are flatly contradicted by the neuroscientific data of recent years. In particular, consciousness students might be forgiven for screaming every time Libet’s veteran 1980s experiment is trundled out. Halligan and Oakley writing in a recent issue of ‘New Scientist’ go down this predictable route. The brain prepares for actions such as reaching out prior to awareness of the intention to reach.
Archive for the ‘Neuroscience and reasoning’ Category
The field of affective neuroscience, initiated by Panksepp and Ledoux, embraces the concept that emotional processes are based on brain structures that operate in parallel with cognitive processes, and can thus influence behaviour independently of cognition.
Studies of neural activity in response to both complex visual scenes and also tastes revealed the neural code for a continuous axis of pleasant to unpleasant emotional values (valence). The medial and lateral orbitofrontal cortices (OFC) supports a valence code that is independent of the sensory origin of signals. This allows the attractive or aversive qualities of signals to be quantified regardless of the nature or modality of the stimuli.
Even at the very early stage of the retina, an important division arises between two parallel visual streams, the dorsal stream and the ventral stream. The dorsal stream projects to the parietal cortex, and is responsible for movements in relation to objects, many of them of a routine or reflex nature. It is also seen as an answer to the ‘where is it?’ location question. The processing of the dorsal is unconscious, and is faster than the consciousness-related processing of the ventral stream.
Consciousness and the Brain, Stanislas Dehaene (2014) Summary and review of the above book INTRODUCTION: On the basis of the brain research of recent years, Dehaene describes both the extent and limitations of unconscious processing. Such processing can extend to sophisticated levels of cortical processing, such as the meaning of words. However, unconscious signals are transient and decay rapidly in the brain, while conscious signals can persist long after the original stimuli. Decision taking Read more […]
By Harlan M. Fichtenholtz & Kevin S. Labar, YaleUniversity and DukeUniversity. Published In:- The Neuroscience of Attention Ed. George R. Mangun, Oxford University Press (2012) Summary and review of the above chapter INTRODUCTION:- Attention and emotion are argued to be parallel processes interacting at many stages in the brain. Some brain regions are more involved with emotional response and others more with attentional control. Limbic regions act so as to bias sensory processing, Read more […]
Perception, Action and Consciousness (Chapter 1) N. Gangopadhyay, M. Madary, & F. Spicer Oxford University Press (2010) This book sets out to discuss a debate within the cognitive sciences as to the relationship of perception and action. One view is that this involves on a dual visual system driving the mainly separate functioning of perception and action. The alternative proposal is a system in which the sensory and motor systems are interactive with perception, and where consciousness Read more […]
Cortical visual systems for perception and action David Milner & Melvyn Goodale, University of Durham and University of Western Ontario In:- Perception, Action and Consciousness – Eds. Gangopadhyay, N., Madary, M. & Spicer, F. Keywords: ventral stream, dorsal stream, Milner & Goodale, Aglioti, Biegstraaten The authors had previously proposed a model in which there are distinct paths for vision for perception and vision for action. This involves to pathways the ventral Read more […]
Independence and connections of pain and suffering S. Benjamin Fink Journal of Consciousness Studies, 18, No. 9-10, 2011, pp. 45-66 http://ingentaconnect.com/journals/browse/imp/jcs As part of his discussion of pain and consciousness, Fink mentions the condition known as ‘pain asymbola’. With this condition, patients are aware of the pain, but not of its unpleasant aspect. It should be stressed that this is distinct from the condition of analgesic patients that have no awareness of pain. Read more […]
Neuroculture: On the implications of brain science for understanding Edmund T. Rolls, Oxford Centre for Computational Neuroscience Oxford University Press (2012) P. Summary of p. 27-65 re: learning P. Keywords: CA3, CA1, hippocampus Learning is based on increases in synaptic strength occurring as a result of the firing of pre-synaptic neurons and the activation of post-synaptic neurons. This is the basis of long-term synaptic potentiation (LTP). The pre and post synaptic activity needs Read more […]