What was the experiment, in brief?
We treated old mice with a low dose of the active ingredient in cannabis. Learning and memory functions improved dramatically in these animals, and they performed as well as mice that were much, much younger.
How did you react when you saw for the first time that old mice had developed younger brains?
Complete disbelief, basically.
How was the experiment conducted?
We implanted so-called osmotic mini-pumps—tiny pumps that we put under the skin of these mice—and they constantly released the drug that we wanted to administer. And then, after four weeks, we stopped the delivery, waited for a week, and then afterwards, there were several tests on learning and memory.
How do you test a mouse's memory?
A very simple test, for example, is that mouse needs to learn how to find a hidden platform. And mice learn this typically within a few days—actually, they're quite good.