What happens in the brain that allows you access to a memory previous unavailable?
For example I forgot the name of someone I've known for years. Two weeks later, without notice, "Diana" popped up.
Why was it not accessible when I found I couldn't remember?
What was the chemistry that occurred that allowed it to happen later?
(Secondarily, is this the same breakdown in dementia and alzheimer's? That is, a breakdown of the 'search memory' mechanism? Or is that the memories themselves are 'losing coherence.')