Let's study ID: retinal design allows prediction of movement (Introduction)

by David Turell @, Monday, August 02, 2021, 19:50 (81 days ago) @ David Turell

How the study shows this:

https://medicalxpress.com/news/2021-08-retina-hardwired-path.html

"Neural circuits in the primate retina can generate the information needed to predict the path of a moving object before visual signals even leave the eye, UW Medicine researchers demonstrate in a new paper.

"'The ability to predict where moving objects will go is so important for survival that it's likely hardwired into all sighted animals," said Michael Manookin, an assistant professor of ophthalmology at the University of Washington School of Medicine. He led the research team with Fred Rieke, professor of physiology and biophysics.

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"To evaluate how effectively the cells were transmitting predictive information, the researchers compared the performance of the ganglion cells to computer programs created to solve such problems. They found that the ganglion cells were nearly as effective at transmitting this predictive information as the best performing computer programs.

"'That the retina, with such simple hardware, is doing these calculations so efficiently is just remarkable," Manookin said.

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"The researchers found that the circuits can extract this information because of crosstalk between the bipolar cells. Bipolar cells are in close contact with adjacent bipolar cells. If one becomes excited by signals from its photoreceptor cells, in addition to sending a signal to the ganglion cell, it also passes some of that excitement along to its neighboring bipolar cells.

"The neighboring cells are then "primed" so that, if they also receive signals from their photoreceptor cells, they are more likely to send a strong signal to the ganglion cell. In this way, as a moving object passes over the visual field, the information about that movement "ripples" through the network of bipolar cells.

"The ganglion cell ultimately collects the incoming information from the bipolar cells and encodes it in signals that provides the brain with information about the motion of the object. With information from many thousands of these ganglion cells about the path of the object, the brain can then quickly predict its trajectory.

"'A 90 or 100 mile per hour fastball can travel more than seven feet before the signals gets out of your retina," Manookin said. "To hit the baseball, you have to be able to predict where it will be in the future. This ability to predict the movement of objects in our environment is also needed in everyday activities like driving a car or even walking. It's an ability so important to survival that evolution has hardwired it into our nervous system.'"

Comment: pure initial design. If this required stepwise development over massive amounts of time, hunting animals would not have survived to evolve the process.


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