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Medicine Science

New Study In Mice Shows That Increasing Serotonin Affects Motivation, But Only In Certain Circumstances (neurosciencenews.com) 47

New submitter baalcat quotes a report from Neuroscience News: A new study in mice shows that increasing serotonin, one of the major mediators of brain communication, affects motivation -- but only in certain circumstances. Furthermore, the study revealed that the short and long term effects of increased serotonin levels are opposed -- a completely unforeseen property of this neurotransmitter's functional system. A surprising behavioral effect, discovered in mice by neuroscientists at the Champalimaud Centre for the Unknown (CCU), in Lisbon, Portugal, strongly suggests that serotonin is involved in a biological mechanism which affects the animals' motivation. The study has now been published in the online open access journal eLife. Serotonin, one of the chemical "messengers," or neurotransmitters, in the brain, is used by neurons to communicate with each other. It plays an important role in the regulation of sleep, movement and other behaviors which are essential for animal survival. But for motivation in particular, it was unclear whether serotonin was involved. Using optogenetics, the team stimulated the release of serotonin from neurons in the raphe nuclei. They first induced "peaks" of serotonin by stimulating these neurons with pulses of light, lasting three seconds every ten seconds, over three five-minute time periods. The mice, placed in a box, were left free to explore their environment. In these conditions, their most frequent spontaneous behaviors are walking around, rearing, grooming, digging holes or keeping relatively still, but nevertheless alert. The only difference the scientists saw was that stimulation caused the mice to reduce their locomotive speed by about 50%. In general, this stimulation of serotonin-producing neurons did not affect other behaviors. The effect of these serotonin "peaks" on locomotion was almost instantaneous (speed reduction manifested one second after stimulation) and transient, with things going back to normal after five seconds. But during this short period of time, "the animals acted as if they weren't motivated," says Zach Mainen, who led the study.
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New Study In Mice Shows That Increasing Serotonin Affects Motivation, But Only In Certain Circumstances

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  • SSRIs (Score:2, Interesting)

    by Anonymous Coward

    As someone who's seen SSRI's "work" on people you most find that they lose what they want to do. For some people want they want is unachieveable, but when someone else wants to be a functional person and instead sits around all day and ends up not wanting to get better, that's not an improvement even if they feel better.

    It'd be interesting to see them continue this in the face of challenges, like shock floors or social situations.

    • Re:SSRIs (Score:5, Informative)

      by Puff_Of_Hot_Air ( 995689 ) on Wednesday February 15, 2017 @08:48AM (#53872633)

      As someone who's seen SSRI's "work" on people you most find that they lose what they want to do. For some people want they want is unachieveable, but when someone else wants to be a functional person and instead sits around all day and ends up not wanting to get better, that's not an improvement even if they feel better. It'd be interesting to see them continue this in the face of challenges, like shock floors or social situations.

      Which is exactly what they did and you clearly didn't read the article.

      “But the same stimulation does not have any effect if the animal is already engaged in a specific task such as running to get a reward”

      The decreased motivation (physical movement speed) was only temporary. The study showed that over a longer period of increased Serotonin, locomotion speed was up by 30%-40% from starting levels; the researches are looking at this as an explanation as to why SSRI drugs take about 3 weeks to start working.

      • Well from personal experience I backup grandparent. Yes myself is not valid scientific B's yada yada.

        I got fired from a job the first time I tried SSRIs when I was younger. I came in late and knew I was supposed to be at work but laid in bed going meh. I was mad at myself for years thinking I was immature and deserved it in which I did.

        I never got connection. I tried SSRIs again recently. Low and behold within a few days I quit studying for my certifications, my apartment became messy, and had a verbal warn

    • by Anonymous Coward

      SSRIs also really fucked up sleep. You're tired all the time and can't concentrate.

      Medication like that should be only used for folks who are clinically depressed anyway - think Gilbert Grape's mom (What's Eating Gilbert Grape). For dysthymia the best thing I found was aerobic exercise. Swimming and running worked much better than anti-depressants, REBT, CBT, Mindsight and every other talk therapy.

      • What makes you think they aren't used on people who're clinically depressed? I've taken them for years, on and off. I am currently on my second week of taking them (again). And just try to get any other kind of treatment in the UK. REBT, CBT, Mindsight? Goodness me. It would either be a great personal expense or an 18 month waiting list (in the UK I mean).
      • Oddly for me a half child's dose helped as I rested more at night with REM. I finally had the energy during the day

    • Re:SSRIs (Score:5, Interesting)

      by dunkelfalke ( 91624 ) on Wednesday February 15, 2017 @10:04AM (#53873103)

      It is an improvement. Given the choice of sitting around all day and feeling like shit or sitting around all day and feeling okay, I'd always go for the latter.
      I lost motivation years before starting taking SSRI.

    • by N_Piper ( 940061 )
      Yes and some people just want to not be contemplating suicide 24/7.
      I've been on SSRI's for most of their commercial existence, I NEED them, I've seen the other side some nitwits had my father doped up so high that he nearly died of serotonin poisoning.
      Yes, too much serotonin causes an "everything is fine" lethargy, I've been there, but if the starting dose causes that it means you have a normal brain chemistry and were sad because things sucked.
  • Maybe (Score:5, Insightful)

    by kackle ( 910159 ) on Wednesday February 15, 2017 @08:36AM (#53872591)
    Being the effect was temporary, could it be they just felt "sick" or stunned? A general brain fog?
    • When I both started and stopped taking an SSRI there were prolonged periods where I was dizzy when turning while walking and shorter periods while driving. There were even a few instances of depersonalization and derealization, so when you feel like you're trippin', you tend to move slowly ans deliberately.

  • Isn't this the same effects we see in drug addicts (of downer drugs obv.) ? An almost immediate reduction in activity as contentment sets in.
    At least I haven't seen an "active" potsmoker.

    I wonder if the long-term effects would be the same for humans and mice as well.

    • by swb ( 14022 ) on Wednesday February 15, 2017 @10:55AM (#53873467)

      I think it really depends on the people. I know a lot of pot smokers who do otherwise repetitive, dull tasks while stoned but when not stoned they start them and then are distracted by something and never finish the tasks. For them being stoned seems to allow them to have a kind of hypnotic focus on the task at hand. My sense is their high level conscious mind goes elsewhere, while their low-level conscious mind can just robotically perform the task in front of them.

      I think this has probably been true and associated with a lot of populations tied to repetitive tasks like agricultural field work.

      Overall I think it's highly specific to the drug in question and to the people in question. With pot in particular people may have a learned behavior associated with "getting stoned" -- it's not just the drug effect, but an entire drug use ritual or process which probably starts with abandoning constructive activity to begin with and following the drug use with pleasurable activity -- TV or video games or something else.

      There was a great article a few years ago about a woman who had a lobectomy for epilepsy that cured the epilepsy by that resulted in a lack of short term memory. After her injury, she went from being a merely good distance runner into a phenomenal ultra-marathoner, and they attribute her stamina partly to her short term memory problems. She doesn't have the kind of short-term distractions and mental fatigue that can plague other people.

      Anyway, I think a similar phenomenon happens with some pot smokers -- they lose partial awareness of what they're doing and for some it makes dull, repetitive tasks easier. Obviously tasks involving complex thinking might be more difficult and associated behaviors with pot smoking may interfere with even simple tasks for others.

      • Fairly accurate.

        When I have some seriously repetitive or physically difficult task that I am avoiding (washing dishes, cleaning house, putting in fence posts, shoveling rocks or dirt, mixing concrete, etc.) weed gives me the motivation to do it and the stamina to finish it. (I live on a farm)

        Anything involving dangerous equipment or serious thinking (chainsawing, taxes, writing reports, etc.) and I definitely do NOT hit the pipe first.

        YMMV.

  • Businesses are trying to figure out how to make employees more motivated. The answer is: ignorance. An operant conditioning box (aka Skinner Box [wikipedia.org]) only works so long as the subject is unaware of the box. The only thing that truly motivates anyone is self interest and a belief that their efforts can achieve it. Once the person has lost the ability to believe they can achieve whatever they put their mind to, motivation plummets to 0. In America, the problem is too many "game theory" players have tricked p
    • by swb ( 14022 )

      And in many cases, they are shattering the long-term motivation by reneging on the essential bargain people believed they had.

      Work hard, go to college, get a good job, and enjoy material prosperity and happiness.

      Years ago we began sabotaging the material prosperity angle, we're killing off the good jobs which also kills off the going to college. You're left with working hard for no possible gain.

      We're segueing back into a slave labor economy where mere survivalism is the sole remaining motivation and that

      • by zifn4b ( 1040588 )

        And in many cases, they are shattering the long-term motivation by reneging on the essential bargain people believed they had.

        Work hard, go to college, get a good job, and enjoy material prosperity and happiness.

        This was covered quite well by Mr. Alan Watts in his talk Life is a Hoax [youtube.com]. He was very much ahead of his time. When you realize these things, you truly do become free at least in the sense of being a free thinker.

        • by swb ( 14022 )

          I mean obviously, our larger social structure has a false quality to it, but really any civilization beyond subsistence agriculture does because of the structural aspects required to make it work. A lot of this just boils down to the demands associated with economics and economic specialization.

          But at a certain point, though, the "rules of the game" have to kind of work to maintain the structure and order of the system. If it doesn't follow the rules, the system will break down.

          • by zifn4b ( 1040588 )

            I mean obviously, our larger social structure has a false quality to it, but really any civilization beyond subsistence agriculture does because of the structural aspects required to make it work. A lot of this just boils down to the demands associated with economics and economic specialization.

            But at a certain point, though, the "rules of the game" have to kind of work to maintain the structure and order of the system. If it doesn't follow the rules, the system will break down.

            Ultimately what is the point of the system? We seem to have gone well beyond the 1st tier of Maslow's Hierarchy of Needs [wikipedia.org]. At what point should the system support the other tiers?

            • by swb ( 14022 )

              I'd say "civilization", but really that question should have been asked about 10,000 years ago when people stopped roaming around and killing things for food and instead decided that the surpluses of sedentary agriculture were more valuable.

              Once we got food surpluses, we had people with nothing to do, casting about for a purpose in life.

              It all kind of reminds me of one of my favorite quotes -- "Civilization is the hopeless race to discover remedies for the evils it creates."

              Or you can just take an existenti

  • I understand where the article is coming from, though. Several years ago, I was prescribed an SSRI for anxiety and depression. The first two weeks of taking it made me feel out of myself, like I was a zombie. It wasn't a buzz, it wasn't a fog, it was just this feeling of depersonalization. The first few weeks could be viewed as "demotivating" because I just really didn't care about much in my zombie like state. Everything was dulled. Over the course of those two weeks, this dullness started lifting an
    • My first weeks were somewhat different - untypically good mood, often giggling about trivial stuff and telling stupid jokes to my coworkers, but not caring much about anything at all. I guess this is how dope smokers feel like when they are high.
      It was fun while it lasted.

    • For me with ADHD it made things worse.

      I almost was fired as I didn't even care if I was late for work. I had to stop taking them as a result. It makes sense as if I feel fine why bother with work and self improvement?

  • So at first the mice chillax, aka get the "hey, maybe this isn't so serious after all" feeling, but their reduced feelings of unease allow them to be more relaxed and healthier = more productive in the long run?
  • I could care less how this or that makes mice into super mice... How about studying humans? (yes I know why they do the studies on mice)

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