Antidepressants might lift up one's spirits, but might they break hearts?
In "Too Hard For Science?" I interview scientists about ideas they would love to explore that they don't think could be investigated. For instance, they might involve machines beyond the realm of possibility, such as devices as big as galaxies, or they might be completely unethical, such as experimenting on children like lab rats. This feature aims to look at the impossible dreams, the seemingly intractable problems in science. However, the question mark at the end of "Too Hard For Science?" suggests that nothing might be impossible.
The scientist: Helen Fisher, research professor in the department of anthropology at Rutgers University.
The idea: Love seems to have three key components, according to Fisher's renowned studies on the matter — sex, romantic love and feelings of deep attachments. "We're studying the brain circuits for each of these now," she explains.
"My feeling is that when you take selective serotonin reuptake inhibitors, or SSRIs, which are common antidepressants, you might be jeopardizing your ability to fall in love or stay in love or both," Fisher says. "When you drive up the neurotransmitter serotonin in the brain, you are highly likely to suppress the dopamine system, and my colleagues and I have clearly found that elevated activity in the dopamine system is linked to one's romantic feeling."
"The chemical relationships are much more complicated than this, but some SSRIs in some people seem to adversely affect the dopamine system, and romantic love gets squashed," she says. "I've gotten a good deal of mail from people who've said they were in a nice short or long romance or marriage with someone that was going perfectly well, and this person started taking SSRIs, and it not only killed their sex drive, but it also killed their feelings of intense romantic love for their partners. I've even had a letter from a doctor in Texas who was prescribed an SSRI and began to realize that he wasn't loving his wife anymore, and he said he'd rather face major depression than lose his feelings for her."
"There are people who are truly depressed who do need an SSRI to get through the day, or just to get out of bed in the morning," Fisher says. "But for the many Americans who may be taking SSRIs but who don't really need them, I would want to know what the effects on love might be. We know perfectly well that SSRIs kills the sex drive in many people, but no one has studied how these drugs might affect other brain systems linked with romantic love and deep attachment."
The problem: To properly investigate this question, "you'd really want to follow a great many people throughout an extended period and measure hormone and neurotransmitter activity both before and after they start taking these drugs, and there's no technology that can really monitor the brain's neurotransmitter activity in real-time like that," Fisher says. "And, in the study, you would also have to ask normal, healthy, not-depressed happy people in good relationships to take the SSRI, and I don't think we would get many volunteers for that. I'm not even sure it would be ethical."
Although one might want to consider regular blood, saliva or urine tests to monitor levels of neurotransmitters such as serotonin and dopamine, "we've tried it, and it didn't work," Fisher says. "Even if you looked at the byproducts of dopamine in the urine, you don't know how quickly it was broken down or how much of it remains in the synapse, for instance, or the number of receptors for it on specific neurons in given brain regions, or how different brain pathways interact with one another. You can't just measure levels of a neurotransmitter — you need an understanding of many brain systems, their complex pathways and their interactions."
The solution? One might be able to question normal, healthy, non-depressed people daily on how their relationships are doing both before and after they start taking these drugs, "but I can't imagine many people would want to sign up for this kind of study either, and once again, I don't think it would be ethical to jeopardize their love affairs," Fisher says.
"Nevertheless, regardless of the difficulties of studying these neural interactions, I do find it remarkable that the medical community dispenses these antidepressants without any studies to investigate how they might affect related brain systems, particularly such important brain systems as those associated with feelings of romantic love and attachment," she notes.
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