Introducing the brain: finding awareness (Introduction)

by David Turell , Saturday, July 22, 2023, 20:09 (488 days ago) @ David Turell

Perceiving and being aware are different parts of consciousness:

https://www.sciencedaily.com/releases/2023/07/230718225629.htm

"After a stroke in the brain's right half, for example, a person might eat only what's on the right side of the plate because they're unaware of the other half. The person may see only the right half of a photo and ignore a person on their left side.

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"This puzzling affliction, called unilateral neglect, highlights a longstanding question in brain science: What's the difference between perceiving something and being aware or conscious of perceiving it? You may not consciously note that you passed a shoe store while scrolling through your Instagram feed, yet you started searching online for shoe sales. Your brain records things that you don't consciously take note of.

"Neuroscientists from the Hebrew University of Jerusalem and the University of California, Berkeley, now report that they may have found the region of the brain where these sustained visual images are retained during the few seconds we perceive them.

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"'The inspiration for my whole scientific career comes from patients with stroke who suffer from unilateral neglect, where they just ignore half of the world," said senior author Leon Deouell, a Hebrew University professor of psychology and member of the Edmond and Lily Safra Center for brain research. "That actually triggered my whole interest in the question of conscious awareness...What is required for something not only to be sensed by the brain, but for you to have a subjective experience? Understanding that would eventually help us understand what is missing in the cognitive system and in the brains of patients who have this kind of a syndrome."

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"'The inspiration for my whole scientific career comes from patients with stroke who suffer from unilateral neglect, where they just ignore half of the world," said senior author Leon Deouell, a Hebrew University professor of psychology and member of the Edmond and Lily Safra Center for brain research. "That actually triggered my whole interest in the question of conscious awareness. How is it that you can have the information, but still not acknowledge it as something that you're subjectively experiencing, not act upon it, not move your eyes to it, not grab it? What is required for something not only to be sensed by the brain, but for you to have a subjective experience? Understanding that would eventually help us understand what is missing in the cognitive system and in the brains of patients who have this kind of a syndrome."

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"...the team found that, contrary to earlier studies that saw only a brief burst of activity in the brain when something new was perceived, the visual areas of the brain actually retained information about the percept at a low level of activity for much longer. The sustained pattern of neural activity was similar to the pattern of the initial activity and changed when a person viewed a different image.

"'This stable representation suggests a neural basis for stable perception over time, despite the changing level of activity," Deouell said.

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"The sequence of events in the brain could be interpreted in various ways. Knight and Vishne lean toward the idea that conscious awareness comes when the prefrontal cortex accesses the sustained activity in the visual cortex. Deouell suspects that consciousness arises from connections among many areas of the brain, the prefrontal cortex being just one of them.

"The team's findings have been confirmed by a group that calls itself the Cogitate Consortium. Though the consortium's results are still awaiting peer review, they were described in a June event in New York City that was billed as a face-off between two "leading" theories of consciousness. Both the Cell Reports results and the unpublished results could fit either theory of consciousness.

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"'Regarding the predictions of the two theories which we were able to test, both are correct. But looking at the broader picture, none of the theories in their current form work, even though we find each to have some grain of truth, at the moment," Vishne said. "With so much still unknown about the neural basis of consciousness, we believe that more data should be collected before a new phoenix can rise out of the ashes of the previous theories.'"

Comment: my view is consciousness involves integration of much of the brain's activity areas.