Quantum Mind Blog

Neural choices

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The brain is viewed as having two systems for making decisions. The first approach is to value actions according to the rewards they have generated in the past. A second or model-based approach uses more flexible evaluation of new or changing options, or works on generalisation from known Read more [...]

Ventromedial prefrontal

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This study shows that human decision-makers adapt their level of persistence in waiting for rewards to the environment in which the decision is being made. Neural signalling in the ventromedial prefrontal, an area involved with evaluation, could evolve differently for identical time delays, if there is a difference in the environment. The neural valuation system is here seen as including the ventromedial prefrontal (VMPFC), the ventral striatum (VS) and the posterior cingulate cortex Read more [...]

Sharp waves and memories

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The consolidation of memories depends on the hippocampus. The hipppocamus generates ripple activity, which is a sharp wave oscillation at 100-300 Hz, mainly within the CA1 region of the hippocampus. Sharp-wave associated field oscillations of the hippocampus, referred to as ripples, are thought to be involved in the consolidation of memories. The median raphe region Read more [...]

Observer’s choices

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The choices of other people are argued to increase the value of such choices for individuals. The related neural processing is encoded in the ventromedial prefrontal cortex, and the signals are predictive of conformity with other people’s preferences. Read more [...]

Libet v. recent neuroscience

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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. Read more [...]

Mitochondria ion channels

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The primary function of mitochondria is to generate ATP that supplies cells with energy. Mitochondria are cell organelles comprising an outer and inner membrane, the latter enclosing a matrix space in which hydrogen and electrons are extracted. The inner membrane contains the respiratory chain; the energy from oxidation/reduction reactions is used to move protons out of the inner matrix and across the inner membrane. This establishes an electrochemical potential gradient across the membrane which allows the synthesize of ATP from ADP. Read more [...]

Dorsal and ventral attention

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Macaque monkeys are often used as models in neuroscience. However, there are important differences between macaques and humans. Humans have a larger dorsal attention network, indicating that evolution has augmented this network. Biases in visual searches are different as between the two species, and Read more [...]