Brain complexity: baby brains under study (Introduction)

by David Turell @, Friday, January 13, 2017, 20:32 (2632 days ago) @ David Turell

Doing fMRI's on baby brains is obviously difficult, but can be accomplished while they nap. They are very undeveloped at birth but appear to have some pre-designed functional areas:

https://www.quantamagazine.org/20170110-infant-brains-reveal-how-the-mind-gets-built/?u...

"They presented babies with movies of faces, natural scenes, human bodies and objects — toys, in this case — as well as scrambled scenes, in which parts of the image are jumbled. Saxe said they focused on faces versus scenes because the two stimuli create a sharp difference in adult brains, evoking activity in very different regions.

"Surprisingly, they found a similar pattern in babies. “Every region that we knew about in adults [with] a preference for faces or scenes has that same preference in babies 4 to 6 months old,” Saxe said. That shows that the cortex “is already starting to have a bias in its function,” she said, rather than being totally undifferentiated.

"Are babies born with this ability? “We can’t strictly say that anything is innate,” Deen said. “We can say it develops very early.” And Saxe points out that the responses extended beyond the visual cortex (the structures of the brain responsible for directly processing visual inputs). The researchers also found differences in the frontal cortex, an area of the brain involved in emotions, values and self-representation. “To see frontal cortex engagement in a baby is really exciting,” she said. “It’s thought to be one of the last spots to fully develop.”

"However, while Saxe’s team found that similar areas of the brain were active in babies and adults, they did not find evidence that infants have areas specialized for one particular input, like faces or scenes, over all others. Nelson, who was not involved in the study, said it suggests that infant brains are “more multipurpose,” he said. “That points out a fundamental difference in the infant brain versus the adult brain.”

"It’s surprising that babies’ brains behave like adults’ brains at all considering how different they look. On a computer screen outside the MRI room at MIT, I can see anatomical images of Riley’s brain that were taken while she napped. Compared to MRI scans of adult brains, in which different brain structures are clearly visible, Riley’s brain seems creepily dark.

“'It looks like this is just a really poor image, doesn’t it?” Kosakowski said. She explains that babies at this stage have not yet fully developed the fatty insulation around nerve fibers, called myelin, that makes up the brain’s white matter. The corpus callosum, a yoke of nerve fibers connecting the two hemispheres of the brain, is only dimly visible.

"At this age, a baby’s brain is expanding — the cerebral cortex swells by 88 percent in the first year of life. Its cells are also reorganizing themselves and rapidly forming new connections to one another, many of which will get winnowed back throughout childhood and adolescence. At this stage, the brain is astonishingly flexible: when babies have strokes or seizures that require having an entire hemisphere of the brain surgically removed, they recover remarkably well."

Comment: Presented to show the forefront of brain science. The baby brain is apparently almost a blank slate at birth, but must contain some guidance in tne neurons' DNA.


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