David Eagleman argues dreaming keeps the visual cortex active in darkness

What was said

"And so what we've realized is dreams are the brain's way of keeping that territory active. every 90 minutes you you have this random burst of activity that just goes blasting into the primary visual cortex and that's it."

David Eagleman says rapid neuroplastic “takeover” effects can begin quickly when visual input is removed, citing observations of visual-cortex activity changes after about 60 minutes of blinding. He and his student Don Vaughn propose that dreaming functions to keep visual-cortex territory active during periods of darkness and sleep, with bursts of activity into primary visual cortex about every 90 minutes.