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New Study In Mice Shows That Increasing Serotonin Affects Motivation, But Only In Certain Circumstances (neurosciencenews.com)
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.
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.
Being the effect was temporary, could it be they just felt "sick" or stunned? A general brain fog?
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.