TR: You said during your presentation at the Picower symposium that we need to study anxiety and depression’s polar opposite, happiness, which may open up a whole new realm of psychiatric treatments.
EK: There may be diseases that are not diseases of too much sadness, but of an inability to enjoy life. My aim is to modulate the happiness component independent of the sadness component.
If we had a good neurobiology of happiness, it might provide a new target for antidepressant medications. Right now, antidepressant medication is designed to relieve your misery. But one of the things that strikes depressed people is their “anhedonia,” their inability to enjoy life. Think of the things you might be able to accomplish if you increased your ability to enjoy life. It’s an interesting possibility.
TR: How would this work?
EK: We have done animal research that begins to open up the biology of happiness. When you teach an animal to fear a tone, by pairing it with a painful shock, you see an increase in brain activity in the amygdala. But when you teach it that the tone is safe, by teaching the animal it won’t get shocked when it hears the tone, you see a decrease in activity in that area. You also see an increase in activity in the striatum – that’s the part of the brain where signals for things that bring pleasure are mediated.
TR: This brain area also processes signals for addictive drugs, so how would a drug that targets this area be different than, say, cocaine? How do you tell the difference between drugs that bring happiness and drugs that bring physical pleasure?
EK: That is difficult to distinguish in an animal. Every time you deal with pleasure, addiction is a danger. I would first look for drugs that decrease the fear signal in the amygdala. And I would try to target the drug specifically enough to try to lessen the likelihood it would have addictive properties.
TR: Are there ethical concerns associated with designing drugs that make you happy?
EK: Every area of neuroscience has ethical considerations. Once we have the biology worked out, society will have to decide whether they want to have this manipulated. Maybe we’ll decide we don’t want to develop drugs in this area. They might be addictive, that’s the most likely of the dangers. They also might have antimotivational consequences – they might decrease the willingness to work.
TR: Any candidate drug molecules for happiness yet?
EK: No, we’re not there yet.