How do chemical reactions in the brain create feelings?

February 22, 2017 8:32 PM

Dopamine floating around in your synapses will make you feel g<ood. But how?

I don't know if I am wording this right but this question has been on my mind for the past couple days. We know how neurochemicals can produce a myriad of feelings in us, e.g. dopamine creates a euphoric feeling, serotonin can induce feelings of well being and happiness. But one thing I am missing is *how* can feelings arise from the changing chemical composition of our brain? There seems to be a gap in my knowledge from "action potential causes release of neurotransmitters into the synapse" to "this causes x feeling." As in what is the mechanism of action that makes this happen? So far my googling has been fruitless.

posted by marvelousmellitus to Science & Nature (17 answers total)

My extremely simple and inexpert understanding is that those feelings aren’t a result of the chemicals floating around; the feelings and the state of the chemicals are one and the same. So “euphoria” (or whatever) is just a word we use to describe what it’s like to have a release of dopamine (or whatever). There is no other mechanism.
posted by Ryon at 8:57 PM on February 22, 2017 [3 favorites]

It sounds like you're asking, effectively, how the physical processes of the brain produce consciousness. I don't think that anyone has ever explained that.

Or, as some wag once put it: "If the human brain were so simple that we could understand it, we would be so simple that we couldn’t."
posted by pompomtom at 9:04 PM on February 22, 2017 [15 favorites]

We don't really know how the changing state of our brains gives rise to any subjective experience at all, feelings or otherwise. It really is an incredibly strange thing. Searching for Mind/body problem turfs up lots of interesting things, at least.
posted by Jon Mitchell at 9:13 PM on February 22, 2017 [3 favorites]

You might be interested in the concept of qualia.
posted by Rhaomi at 12:15 AM on February 23, 2017 [2 favorites]

Emergent properties are emergent. I realize that isn't a super satisfying answer, but when you're dealing with a complex (and not just complicated system) it's really hard to establish a deep understanding in a sentence or two.

That said, if you want deeper understanding of this kind of thing, I know a great series of videos. Human Behavioral Biology with Robert Sapolsky. The guy is brilliant and a damn good lecturer to boot. The drawback? I've just handed you just shy of 40 hours of lecture to watch. But trust me - pretty awesome.
posted by Kid Charlemagne at 1:17 AM on February 23, 2017 [5 favorites]

You've asked one of the Very Big Questions. Plenty of theories, but no-one really knows.

Couple more links, if you're interested in further reading:

Wikipedia page on what's become known as the "hard problem of consciousness".

More technical (in the philosophical sense) treatment of surrounding questions

I like this book by Daniel Dennett - but an equal & opposite no. of others think he totally misunderstood / avoided the question, so don't take it as a definitive account.
posted by rd45 at 1:43 AM on February 23, 2017 [1 favorite]

On similar lines to the above, I recommend Thomas Metzinger's book, The Ego Tunnel.
posted by crocomancer at 3:28 AM on February 23, 2017

I think we might be going too deep too quickly. You know that dopamine is a neurotransmitter, used by neurons to signal each other. It's not odd, then, that having more of it around increases the level of activity. But not all neurons are the same and they don't all use the same repertoire of neurotransmitters in the same way, so dopamine affects the level of activity of different parts of the brain differently. Now if this has effects on the parts of your brain that assess your safety, available energy, and stuff like that, it's not hard to see that that might have a systematic effect on your mood and the likely style of your behaviour. I think we can conclude that much without having to rouse the philosophers from their fitful doze.
posted by Segundus at 3:45 AM on February 23, 2017 [5 favorites]

Well sure, but why should dopamine make you feel good, not, say, anxious? Why do the neural patterns that fire when I hear a trumpet playing B-flat make me have trumpet phenomenology, not, say, an experience of tasting a strawberry? There seems to be no connection at all between the realm of a bunch of neurology, electricity, and chemicals, and the character of conscious experience. It's a category error to think that the "hard problem"can be dissolved by doing a bunch of more brain science. The problem is that we don't seem to have any explanatory framework that could resolve it. And dualism just pushes it off into a "dormitive virtue" style explanation.
posted by thelonius at 5:33 AM on February 23, 2017 [1 favorite]

Dopamine makes you feel good because it particularly affects the parts of the brain that do 'good feeling' - which we can analyse quite a bit further if we want, into things like perception of safety, health, and what have you. It won't do to say there's no connection at all between neurology and the character of conscious experience. We've got things like colour spaces mapped out in neurons and activity there determines what colour you're experiencing.

I'm not saying the Hard Problem can be solved by neurology, merely that I think answering the question here doesn't require us to solve the Hard Problem. I might be misreading what the OP wants, of course - maybe a crash course in phenomenology is just the ticket.
posted by Segundus at 5:53 AM on February 23, 2017 [1 favorite]

I think it's more simplistic and primal than the answers upthread. When we're babies, close contact with our mothers releases oxytocin (it's also in breast milk). This happens in monkeys and perhaps all mammals. We "feel" safe with our mothers (putting feel in quotes because as babies we don't have the language or context to describe it). Later in life when oxytocin is released (e.g. during sex), we associate it with that safe, good feeling. I'm not sure what the analogy would be for dopamine and serotonin (what makes babies feel euphoria?) but it's the same concept.
posted by AFABulous at 9:35 AM on February 23, 2017

We don't really know,but I will note that the word "feel" can refer to either physical sensation or emotion. I don't believe that is some wild coincidence.

I will suggest that perhaps part of the mechanism is that when the body has sufficient resources to produce specific chemicals, this serves as a kind of leading indicator for important information, such as nutritional status and general wellness. Thus, the sensation produced by a cascade of X chemical gets assigned positive or negative meaning, depending on what it signals about our underlying physical state. It eventually can develop into a specific meaning, based on what it consistently tells us about our health, wellness, relationship to the world around us, etc.
posted by Michele in California at 10:31 AM on February 23, 2017

If you're asking a philosophical question, then your premise is incorrect. The chemicals and neurons in a particular brain state don't "produce" feeling. They are the feelings. Remember that all of reality, including our perception of a brain with chemical and physical mechanisms is a product of the reality our consciousness constructs. We have no access whatsoever to whatever "real" reality may be out there or, for that matter, any particular reason to believe that there is one.

If you're asking a neuroscience question, then no one knows. If we did, we'd be on our way to synthesizing conscious brains.
posted by cmoj at 11:05 AM on February 23, 2017 [1 favorite]

There seems to be a gap in my knowledge from "action potential causes release of neurotransmitters into the synapse" to "this causes x feeling."

It's because nobody knows the answer - this is one of the hard problems in cognitive science, the Binding Problem (sorry, that wikipedia page is terrible).
posted by soylent00FF00 at 6:57 PM on February 23, 2017 [1 favorite]

I once took Wellbutrin for a short period as a way to alleviate feeling depressed. During that time I became aware of a sensation in my awareness that seemed like a chemical signature. If our mood and affect are simply the sum total of all the chemicals our brains and body are creating, this one chemical was suddenly turned way up high. Normally you wouldn't think of your mood as a bunch of chemical notes. In my case, the only analogy I could come up with was color or light. It was if a light had gone on in the attic of my brain and stayed lit all the time, 24 hours a day. The frequency did not change, it didn't go up or down with the weather or the time of day or the seasons. I could see that in some ways this chemical, or color, had some relationship to the sensation of happiness, but really had no more connection to the overall sum total of happiness than a seat cushion has to the function of a chair. It's just a part of it.
I quit using Wellbutrin soon after and slowly the sensation faded. I don't now detect my mood or affect as being part of a chemical sea of notes, but from my experience believe that it basically is just that. Our awareness has no evolutionary need to know the underlying chemical strutures. We don't detect the drip of dopamine or a surge of serotonin, only the mood it creates as part of a dynamic whole in an immensely dynamic, sensitive and subtle system.
posted by diode at 8:11 PM on February 23, 2017

I like this book by Daniel Dennett - but an equal & opposite no. of others think he totally misunderstood / avoided the question, so don't take it as a definitive account.

Consciousness Explained does a decent job of tracing the processes that lead to the perception of an inner monologue or stream of consciousness, but it's pretty light on the qualitative aspects of consciousness like emotion. It also doesn't delve much deeper into the mechanics of experience than referring to task-associated brain regions and definitely not at the level of neurotransmitter levels. A good book, but not a good place to look for answers to this question.
posted by murphy slaw at 4:41 AM on February 26, 2017

I wonder this myself. I wonder if the physical brain is just an abstraction that God created... that in the end whatever we feel and perceive and remember is because something is going on in the background that is unknown... for now.
posted by hellomina at 5:03 AM on February 28, 2017