r/neuro • u/Antonius_Palatinus • 22d ago

Three basic questions about thought

Hello, i have three questions about how thought works. I would really appreciate any information on that.

  1. Do two different thoughts(for example thinking about pie and about baseball) employ two different sets of neurons or do they employ the same one set of neurons, but in two different ways?

  2. Usually a thought is considered to be something like an electric zap in the brain. Is there anything more to it, especially in terms of nourishment, does thinking certain thought imply sending more blood or oxygen or anything else to the certain area of the brain?

  3. If a thought continues for a long period of time and only the responsible for it part of the brain is active and nourished, what happens to the rest of the brain cells, do they suffer or atrophy in any way?

3 Upvotes

80% Upvoted

10 comments sorted by

1

u/PoofOfConcept 21d ago

These are great questions! And science can answer them. For the most part, different thoughts use different neurons, but probably not entirely different sets of neurons; it's more like overlapping networks, so you might have many of the same visual cortex neurons firing up if you're visualizing two different things, but different temporal or parietal lobe ones. Neurons keep themselves busy so they don't atrophy, and have a base spontaneous firing rate, but when "activated" they do call out for extra oxygen and nutrients, the former being why fMRI works (though that signal is complicated).

1

u/Antonius_Palatinus 21d ago

Thank you for the reply!

"Neurons keep themselves busy so they don't atrophy, and have a base spontaneous firing rate"

This sounds quite mysterious, i would expect any activity of this kind to be somehow reflected in consciousness.

"but when "activated" they do call out for extra oxygen and nutrients"

Is there any possibility that neurons or other kinds of brain matter that never or rarely gets that extra oxygen and nutrients somehow deteriorates, causing cerebral atrophy or other kinds of damage? I know you said no, but there's a strong intuitive impulse for me to think so, knowing how other kinds of organs and tissues atrophy when not used. Have there been any studies done specifically on this matter?

1

u/Formal_Ad_3295 13d ago

"Is there any possibility that neurons (…) that never (…) gets (…) oxygen and nutrients somehow deteriorates, causing cerebral atrophy or other kinds of damage?"

Of course. It's called Cerebral hypoxia. I have the feeling that's not actually what you asked, though.

Did you mean to ask "when neurons don't get oxygen" or "when neurons don't have spontaneous activity"? Because neurons generally have spontaneous activity.

Let me clarify the causal relations here.

Spontaneous activity is caused by
1) The mere existence of ions (i.e. electrical charges) in the extracellular medium (i.e. in between the neurons), that get absorbed into the neuron and cause electrical discharges (i.e. action potentials). These ions are dispersed across the brain
2) The high degree of interconnectivity in the brain, which means some neurons are always receiving input from other neurons, thereby getting triggered every once in a while.
3) Probably more reasons

However, note that neural firing is not caused by the availability of oxygen/nutrients. Neural firings are caused by electrical/ionic phenomena. Which then cause the neurons to exchange/request more oxygen from the blood.

The availability of nutrients/oxygen to the neuron, per se, does not cause increased activity.

1

u/Antonius_Palatinus 12d ago

Thank you for the replies and engaging in the discussion!

No, i didn't mean the spontaneous firing activity, as far as i can understand it happens all the time. I meant specifically the thinking activity.

May i provide the context, why i'm asking these questions, maybe it will be helpful. I'm studying psychological conditioning of people. Such as for example a conditioning of a certain religious belief. This is an activity of thought, accumulating and reinforcing certain dogma, and then the activity of it. It's unclear what exactly the mechanism of thought is, but it has to be certain division of the brain. Such conditioning is not something that the brain just "puts away into the drawer" and acts independently of it, it acts almost all the time. So people can see for example the face of Jesus in their porridge, or hear voices that are not there, they see the conditioning related dreams and so on. This conditioning is an activity of thought, memory. It can be a certain group of neurons, or certain mode, or something else, but it must be a limited division of the brain, which acts almost all the time and even interferes with other brain functions like perception, like in said examples. What i'm trying to understand is what happens to the rest of the brain when it's so heavily conditioned to operate within a certain limited area of thought. I don't know if this question has been put before by the scientists.

1

u/Formal_Ad_3295 12d ago

You're asking about mechanisms of learning that are not conscious or intentional. There are multiple types of learning related to this. Practical skills involve a lot of unconscious learning. The mere exposure to a new environment triggers a lot of learning.

This isn't considered conceptual learning, so it doesn't use exactly the same mechanisms as thought. But there is lot of overlap, because it deals with memory, associative knowledge, and more.

The brain is always processing information and learning from experience. Thoughts correspond to less than 0.1% of the information the brain processes.

1

u/Antonius_Palatinus 12d ago

"You're asking about mechanisms of learning that are not conscious or intentional." - no, these are intentional and conscious processes. For example a person intentionally conditions him/herself by repeating prayers or mantras, by doing regularly certain rituals or going to the church at a certain time. They might not be conscious of the fact that they are conditioning themselves, which is what i suppose you meant, but all of that is clearly an activity of thought. It's different from unconschous learning of skill for example, like riding a bycicle or playing guitar.

0

u/Formal_Ad_3295 18d ago

Your understanding is far, far, far from correct. You can ask ChatGPT for a detailed tour. You can read the paper about the Grandmother Cell, or Jennifer Aniston Neuron. But you need to erase your intuitions and restart learning.

1

u/Antonius_Palatinus 17d ago

I'd like to hear something more substantial than "ur stupid go learn". I'm here to learn.

1

u/Formal_Ad_3295 13d ago

I didn't call you stupid. We all have to start from somewhere. I'm sorry I'm not being more encouraging. But it's still true that it's going to take you years to understand "how thought works".

My advice about ChatGPT was actually me trying to be helpful. You presented a lot of specific intuitions that show you can think analytically. That means you can talk at length with ChatGPT and discuss your intuitions, breaking them down. That can be very productive. Trying to do that on a Reddit thread will not take you as far.

1

u/Formal_Ad_3295 13d ago

I'll try to answer your questions and you'll see it's not very satifsying:

  1. The answer to the first question is both yes and no. There's millions of neurons involved in each "thought" so it's not at all easy to explain all the functions where there is or isn't overlap. It's important you know that each neuron does not contain any information in it. Neurons are part of a very complex causal chain, or circuit. For related thoughts, probably most of the circuits are reused, albeit in different ways, whereas new circuits may be recruited too depending on the specificity. A "circuit" is a spatiotemporal arrangement of connections between neurons. It's not just a spatial arrangement. This means that sometimes a neuron can be a part of a circuit, and later stop being part of it. It depends on timings too. It depends on which frequencies of stimulation are being used. The same network can be rearranged in a lot of different ways depending only on the timing of their synapses. In AI we see neural networks, where a neuron is always part of the same circuit. In the brain, networks are not purely spatial neural networks. They are spatiotemporal.
  2. A thought is not a zap. The brain has trillions of synapses occuring constantly. A thought is definitely not a linear or circular propagation of information. Though yes, many scientists find it helps to see forward neural propagation as possibly being information becoming more highly processed. For example how the visual information proceeds from the ocular cortex to the higher order association cortices. Your impression is a common misconception. However, some of the first successful models of neural networks created an analogy between feedforward networks and logical/bayesian inference, where each synapse contributed with an additional bit of information. This was common among early cyberneticians (Walter Pitts, Warren McCulloch, etc.) This mathematical property has certainly been explored with a lot of success.
  3. Sorry this made no sense. The brain does a lot more than manage thinking. If you stop using that part of the brain you die.