New Insights Into Weed And Memory

brain memory experiment mice maze

Salutations! As you may or may not have guessed, I am a not-so-very-young man of science. Let’s just say that I have advanced well past the age where I need to show some ID to get into a coffeeshop. That’s part of the reason why I, Professor Harvest, am sometimes encouraged by some of the studies I get to review. Today, for instance, I found an article by Scientific American that had some excellent news for the, er, more mature smoker such as myself. A group of German researchers have conducted a series of experiments that cast doubt on the popular image of the ever-forgetful pothead. Well, not so much every absent-minded smoker in fact, but rather the cannabis consumer of a more advanced age… Yes, that’s right guys: I think I may have some good news for any of you who identifies as a senior stoner!

What I Found

The study, published in Nature Medicine journal last Summer, reports on a clever range of experiments involving groups of mice and lots of THC. The general setup was this: first, the mice were divided into three groups according to age. They were distributed across a young mice, mature mice, and an old mice group. Then, half the mice in every group were given low doses of THC, which you’ll recognise as the natural cannabis compound that gets you high. The mice of all six subgroups were then observed as they had to perform learning and memory tasks. One task included escaping from a maze filled with water onto a hidden dry platform. Yes, I know what you’re thinking: those German scientists are a bunch of sadists; but rest assured that it all happened for science’s sake and the mice were relatively unhurt. Then, the mice had to show how well they recognised the faces of mice they had just met a little while ago. The results of these experiments were quite a surprise. To the researchers, that is – the THC-drugged mice were not very impressed at all, I expect.

Memory Lane

The outcome of these experiments was not necessarily a trip down memory lane; or at east, it wasn’t for all of the mice involved. Unsurprisingly, and wholly in line with the stereotype of the youthful dazed and confused stoner, the young mice were crap at both the memory tasks. Well, the ones with THC in their brains were, that is: the sober youthful mice had the best scores of all six groups, regardless of age and THC levels of the others. None of the rodents drowned in the water maze, mind you, but the young stoner mice just didn’t seem all that interested in getting out of that pool… The youthful THC mice took quite a while to figure out how to get to that platform, even though they had been shown the way before they got high. Likewise, they did a poor job at recognising some other mice they had met just recently. If you’ve ever been at a party and got stoned along the way, the experience may sound familiar: “Hey, do I know you? Oh well, never mind, I’ll just float around in this pool some more, yeah? Got any snacks on you, bro?”

experiment THC and memory mice
Experiment  mice and the influence of THC on memory

The Not-So-Young Mice

The performance of the mature and elderly mice groups made for an altogether different story, however. Some of the results were according to expectations: the sober old mice performed poorly at both memory tasks, and the elderly mice were even worse than their slightly younger mature pals. The senior stoner mice, however, completely reversed the expectations of the researchers. Rather than just slump in a corner of the maze somewhere, or swim in endless circles trying to find the toilet facilities, they actually performed better than anyone thought they might. The mice of the oldest THC group actually did so well on both tasks that they matched the youthful sober group on either account! The middle-aged mice performed as expected while sober: they got medium results scoring somewhere between the young sober ones and the elderly sober mice. When fed THC, their performance dropped slightly, but not as much as that of the youngest peer group. It seems as if THC impairs the memory functions of young mice, but as they get older, that very same THC appears to boost memory instead!

Remember To Get Stoned As You Age?

Alright, a tiny little dose of perspective is in place here. Sure, these results are spectacular. Apparently, there is a lot to be learned about how our lovely cannabis plant may prove helpful to an ageing world population. But let’s not get ahead of ourselves here. As an external expert reviewing the study pointed out, these experiments involve mice, not humans, so the results can’t simply be copy-pasted onto regular folks like you and me. Also, we don’t know exactly how THC jogs memory in older mice while blocking it in youger animals. It would be tempting to just put up signs all over town saying “Remember to get high, old-timers, and you’ll never forget your grandkid’s birthday again!”, but we need further research before we can start fantasising about spending old age on a permanent weed buzz.


Still, even if you consider that further studies involving human subjects are necessary to make any claims on the mental health benefits of cannabis, these findings are quite promising. I, for one, can imagine myself kicking back in some elderly home a decade or two from now, chilling out on a bong full of weed – all on doctor’s orders of course, just to keep my memory in shape. I say let’s do this, and to hell with crosswords! As further studies are bound to receive the green light in the near future, I’ll try to keep you posted on the results. Luckily for you, I have just the thing to make sure my poor old brain remembers…

All yours, Professor Harvest