Do other animals get addicted?

Amy - So, I don't know. I'm not an expert on goat addiction, but I did go and look this up. There's a little bit of discrepancies to whether it's goat or sheep, but there are certain populations of sheep and/or goats who will consume lichens and will grind their teeth down. Some lichens have psychoactive substances in them, so narcotics and hallucinogens for instance. So, this is sort of quite an unusual example of I guess a natural addiction occurring in animals.

You'll also see it actually in some monkeys. And monkeys that are near tourist resorts will go and steal cocktails from their guests and get drunk on those. I think there's also some incidences of elephants consuming overripe slightly fermenting fruit and becoming drunk. That's not necessarily the same as being addicted, but it's sort of a nice example of drug use in animals.

Animals do get addicted which is useful for those working in addiction because my lab for instance specialises in rodent models of addiction. And rats will use any drugs of abuse that humans will, with the exception of LSD actually, but I suspect that LSD is probably not that pleasant if you don't know what to expect from it. But all other drugs of abuse - heroin, amphetamine, cocaine, alcohol - the rats will use.

And interestingly, the population of rats that satisfy the diagnostic criteria for addiction is the same proportion as in human users. So, if you allow population of rats to use cocaine for instance, about 20% of those animals will work for that cocaine despite adverse consequences will escalate their use, will lose control over when they use. The other 80% of the animals will use it, but they can take it or leave it which is really similar to what you see in the humans.

Hannah - Thanks, Amy Milton from the Department of Psychology at Cambridge University. If you've got any burning questions about your brain and the nervous system, just email them to neuroscience@thenakedscientists.com, you can tweet us @nakedneuroscience or you can post on our Facebook page and we'll do our best to answer them for you.