학습과 기억: 신경과학의 미래

 

학습과 기억: 신경과학의

미래(1)

 

강남대 이상복교수 통역용

 

 

http://mitworld.mit.edu/video/332

 

About the Lecture

What better way to inaugurate one of the world’s premiere neuroscience research centers than a tour highlighting some of the field’s most exciting work.

Susumu Tonegawa provides not only a history and overview of the Picower Institute, but a rundown of the latest insights about memory and cognition emerging from his and colleagues’ labs. Morgan Sheng has figured out how to visualize at high resolution the molecular architecture of neuronal synapses; Matthew Wilson can detect a pattern of firing neurons in the formation of spatial memories as rodents explore a new environment, and then watch these neurons firing in the same pattern as the animals sleep—suggesting a mechanism for consolidating memory; Mark Bear is delving into the molecular mechanism behind fragile X mental retardation, and exploring possibilities for pharmacological correction; Earl Miller’s work with monkeys indicates that learning may happen first in a more primitive area of the brain, monitored and then ‘approved’ by the brain’s executive branch, the prefrontal cortex. And Tonegawa has zeroed in on the genes responsible for specific kinds of memory circuits in the brain’s hippocampus. As for the future, Tonegawa calls for “new technology, based on totally new principles, which can analyze what’s going on in the brain at the level of a single synapse,” as well as new diagnostic and therapeutic methods for psychiatric and neurodegenerative diseases.

Sydney Brenner says the “connection between genotype and phenotype, especially for complex animals, will remain the most challenging problem in biology.” He says there are deep intellectual problems to be solved, such as computing behavior “from a wiring diagram,” which must be accomplished if we are to gain understanding of the brain.

Richard Axel probes the mechanism of perception, from the bottom up and top down. He asks how the brain “creates its own selective pictures of the world” from different sensory input, which exist as “bits of electrical activity, excitable neurons.” Whether for vision, hearing, touch or smell, the brain has receptors that are specific for certain stimuli. Different odors, for example, will activate a different combination of receptors, which will in turn activate specific parts of the brain. When the fruit fly smells banana, one set of neurons fire, and when apple, quite another. The same is true for humans. But the problem of how our brains reconstruct this information in a meaningful way hasn’t been solved. Says Axel, “Perception is only a hypothesis, a best guess that never truly approaches reality.” Since “the brain does not have eyes,” wonders Axel, “who reads the map?”

 

 

학습과 기억: 신경과학의 미래(2)

 강남대 이상복교수 통역용

 

http://mitworld.mit.edu/video/333

 

About the Lecture

If the century just passed was “the province of the gene,” then the next hundred years shall be “the province of the mind,” believes Eric Kandel. Brain science is poised to reveal the biology of conscious and unconscious mental processes involved in perception, emotion, thought and action. There will also be “a revolution in understanding mental illness,” with animal models revealing the “mechanism of pathogenesis.” We shall gain an understanding of the biological underpinnings of personal wellbeing, using imaging to reveal the pathways in the brain involved in joy. Scientists have singled out one gene that in such animals as voles determines whether they will socialize, or act as loners, suggesting the possibility of molecular insight into social and aggressive behaviors. What’s more, says Kandel, neuroscience will suffuse all the disciplines: sociology will have to consider a “biology of free will;” economics must take up the biology of decision and choice; art appreciation will have to account for how sensory information gets processed, such that when “two people look at the same object, one finds it beautiful and the other finds it boring.” And psychology will become indistinguishable from neuroscience, leading to a common base of training for neurologists and psychiatrists.

A contrary James Watson offers a dose of skepticism around the direction of brain research described by his colleagues. In the words of his old partner Francis Crick, “we haven’t found the double helix of the brain and don’t know how to think about it.” Some “gigantic problems” exist, says Watson: How is perceptual information stored; what does it look like; and how does information get pushed from one part of the brain to another? Key to cracking these questions, in Watson’s opinion, will be a deep understanding of brain evolution. He also recommends delving further into the genetic basis of mental disease, which might uncover an underlying defect in neurogenesis -- the growth of new brain cells. Perhaps all mental disease will ultimately be characterized as a “deep learning defect.” Watson is much concerned with “why we lose the ability to learn as we get older.” He believes it must be because “the brain is finite—we can only have so much stored.” But while he plays tennis and reads books partly in the hope that they will expand his mind, Watson also looks to biology for a way “to speed up neurogenesis in adults, and raise IQ.”