[D] What are Geoff Hinton's current thoughts on backpropogation as a learning mechanism in the brain?

I watched a lecture of his from about 4 years ago where he swats down all of the objections to backpropogation as a learning mechanism in the brain. But I recall hearing him on a podcast more recently (can't find it anymore) in which he was skeptical of backprop, and seemed to suggest that Hebbian learning was more important. I'm curious to know his current beliefs and why. What it the most recent interview or lecture where he discusses this? …

brain current geoff geoff hinton hearing hinton lecture machinelearning podcast recall thoughts