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Paul B.'s avatar

What do you think about short-term recreational drugs that impact serotonin (e.g., MDMA, psychedelics)? These and particularly MDMA do not blunt emotion. Would you have to just say that serotonin has many roles and these modulate some other role?

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AffectiveMedicine's avatar

MDMA has a methamphetamine-like quality and also increases dopamine and norepinephrine, so it's not clear how much to ascribe the positive affect of MDMA to that.

Yes it is fair to say that serotonin has many roles related to its many receptor subtypes.

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Jenny F.'s avatar

I was diagnosed with OCD at 17, lost that diagnosis, got diagnosed with GAD and depression in college, lost those diagnoses, was diagnosed with adjustment disorder….and so on. Lost all diagnoses later in adulthood. I’m just a normie now and happy that way. Freud would have called me a teenage hysteric.

I notice how much emphasis there is in this piece on “feelings.” I find this deeply bizarre. For me, whatever-I-was-dealing-with was ALWAYS physiological and embodied. I fell asleep at odd hours, lay awake at 3am. My heart beat out of my chest. I experienced rolling waves of hot and cold flashes. I physically shook. I tingled all over. I fainted in college several times, and woke up extraordinarily embarrassed (I was also very shy and tried to avoid public spaces where possible). I was entirely preoccupied with preventing and then coping with these enormous sensations. The one thing that ultimately helped was going to a somatic experiencing therapist who helped my body literally, simply, find a state of calm. Once I had experienced calm- for the first time in a good 15 years - I was able to return to that state, again and again.

Physiologic embodied states are not rightly named emotions, feelings, or behaviors - are they? Do you actually mean to refer to, e.g. “hot and cold flashes” when you write out the word “feeling”? They are the root cause *of* bizarre behaviors (adaptations to deal with the internal states) - as we know from autistic people, who have shared extensively about the ways in which stimming functions as a coping or adaptive mechanism. I did a whole lot of bizarre stuff, including screaming out loud on escalators and engaging in OCD-like rituals, entirely as way to try and *make the physical pain stop.* I wasn’t able to stop the bizarre behaviors until the physiologic symptoms went away.

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MEL's avatar
Feb 16Edited

> the Mad in America crowd ... are dumb.

You lose all credibility with this statement.

Side-effects of SSRIs include psychosis, murder, suicide, and chemical castration (PSSD), even in patients not taking them for mental health reasons. Mad in America acknowledges this, but you do not. Mad in America points out the fraudulent nature of SSRI studies, and that their advertised mechanism of action — increasing clinically low brain serotonin — is a conscious fraud.

It would be far more accurate to say the Affective Medicine crowd is dumb.

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Hugh Hawkins's avatar

Don't classical psychedelics (like LSD and psilocybin) amplify emotions? And don't they act by being serotonin agonists? "Amplifies emotions" seems like a decent descriptor of what they do to mood. Someone feels a little anxious, suddenly they're having a full-blown panic attack. Someone is feeling alright, suddenly they're feeling the happiest they've ever been.

But obviously, this is opposite to your theory of how serotonin is working. What do you make of all this? Is there some reason why serotonin analogues would contradictorily increase emotions?

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Robertas's avatar

It's more complicated than "serotonin inhibits emotions". SSRI do, yes. But serotonin acutely, itself? No, analogy from psychedelics and MDMA that suddenly increase serotonergic function - emotions are amplified massively! Only with consistent stimulation of serotonergic receptors by SSRI, after 2 weeks or so their sensitivity decreases and this coincides with therapeutic effectiveness. So does serotonin inhibit emotion? No, not really, it amplifies them, but if you overkill the system, then it shuts down, and emotion is reduced.

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Isha Yiras Hashem's avatar

Thanks for explaining why people can't become endlessly happier by taking higher doses of SSRIs.

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Create your profile's avatar

I didn’t read any of your citations, so I apologize if they would all have make the answer to this obvious: How do you either reconcile this with or refute the “computational psychiatry” model of serotonin mediating the confidence of predictions? It’s easy to say that exogenous serotonin receptor agonists causing hallucinations is incomparable to endogenous serotonin’s activity in the brain, but why would less precise and/or confident predictions - to any degree - have the consequence of less emotion? Or, if it doesn’t, why is this model superior?

Thanks - glad to see you writing!

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AffectiveMedicine's avatar

Thanks for your thoughtful comment and encouragement.

I think these views are consistent with each other; it's three blind men and an elephant situation. Though I don't know much about the psychedelic angle.

My understanding of the computational view is that serotonin reduces precision/confidence (very over-generalized) of predictions, which again puts it opposed to other neuromodulators like dopamine and acetylcholine.

We could think of emotions as highly weighted, rapidly activated predictions (heuristics). If you see an angry bear, you REALLY want to run away right now. It is difficult to overcome this prior, and acting on a high confidence prediction tends to pay off compared to sitting and musing about it.

So "serotonin makes predictions less precise/confident" is another way of saying it turns down the valence or weighting of those emotional impulses and promotes long-term consideration and planning.

Here are a few quotes from Colombo's "Serotonin, Predictive Processing, and Psychedelics (2022)":

"Specifically, according to one of these hypotheses, serotonin represents expectations about negative outcomes (i.e., punishments or negative rewards) and, on the basis of these representations, it would compute appropriate inhibitory motor responses (Dayan & Huys, 2009). If this hypothesis is true, increased serotonin activity will promote the downregulation of impulsive emotional reactions to expected punishment or provocation, boosting patience and coping with anxiety."

And:

"According to another hypothesis developed within the RL framework, serotonin computes the time and resources available for action, learning and development”...Higher serotonin activity in a decision-making task would signal that there is enough time available for deeper deliberation, more explorative choices and longer-term predictions of the likely outcomes of different choices."

More broadly, I find the predictive processing theory and computational approaches unintuitive. Not saying they're wrong, just hard to understand. I'm not that mathy, but I believe that predictive processing is conceptually similar (and mathematically equivalent?) to control theory. Feedback loops are easier to grasp, and my model of the entire nervous system is a stack of nested control loops. I think this is a restatement of predictive processing theory, not a competitor, so for instance the "prediction error" is just error (SP-PV). This is how we already talk about physiology in the body (cardiac and endocrine systems) so it's more consistent with the rest of biology and medicine.

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Create your profile's avatar

I’m not sure it’s right to equate emotions with heavily weighted predictions or that this squares with computational models of mental illness, but that’s not what your post was about and computational theory leaves a lot unclear, so I don’t want to drag the conversation down that path.

Does “serotonin inhibits emotions” make accurate predictions about what SSRIs can and can’t treat? Some are also used for anxiety, but, to my understanding, the closest there is to a disorder in which all emotions, with little or no respect to content or direction (unlike anxiety), are insufficiently inhibited is borderline personality disorder: do SSRIs treat that? Conversely, do SSRIs treat any disorders which themselves inhibit emotions?

Thanks!

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AffectiveMedicine's avatar

Feedback to this piece has made me want to understand predictive processing better, particularly how it conceptualizes emotions. So I am going to look into that topic more.

I agree that BPD might be aptly described as "way too much emotions." Interestingly, there is not good evidence for any medications treating BPD, though individuals with BPD often end up on multiple meds, including SSRI, mood stabilizer, antipsychotics, benzos, stimulants, etc. There are bunch of systematic reviews on pharmacological treatment for BPD, which find weak evidence for a handful of med classes, thought details vary. I don't have a good explanation for this, except that BPD has many manifestations and potential endpoints to look at, which makes it hard to study.

Disorders of too little emotion is an interesting idea. Depression can certainly lead to flatness and apathy. My gestalt which I reference in the piece is that this type of depression does not respond as well to SSRIs as to bupropion, which is more activating. I also think about OCPD (no meds used for that) and antisocial personality (lack of guilt?) where meds are also not used except for impulsive aggression.

Your questions are very insightful, thanks!

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For Lack Of A Better Word's avatar

I'm currently on an NDRI inhibitor. Do we have a good idea neurologically of how those treat depression? I feel like it puts a floor on my mood, mainly.

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AffectiveMedicine's avatar

Thanks for commenting. I assume you're referring to bupropion. Norepinephrine is a non-specific neurotransmitter that generally acts to increase alertness, arousal, awareness re the external environment, things like that.

There are several theories about dopamine; I like Jaak Panksepp's work; he argues that dopamine is the basis of the SEEKING system; which is a basic affective system that prompts animals to "engage in enthusiastic investigations of their environments" and correlates to feelings like excitement, interest, and anticipation. I think of this as "mood" in the purest sense.

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May 31, 2024
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AffectiveMedicine's avatar

Thanks for commenting. I don't see a conflict here. For one, I think you can just as easily say that thoughts come from emotions. But everything runs in both directions. A very, very simple model might have 4 layers of control, each with the potential to both activate and inhibit the layers above and below. The layers could be cognition ("cognitive control" is a common term), emotional feelings, the body, and the environment. Each is affecting and being affected by the others. You end up with a hugely complex dynamical system that can fall into many different equilibria.

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