Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

How do random thoughts come to our mind?

  1. Jan 29, 2015 #1
    How we are able to recollect things and how random thoughts are generated in our mind?
    Is there any specific reason?
    As I can't edit my thread title, as I realize the topic should have been How random thoughts come to our mind?
     
  2. jcsd
  3. Jan 29, 2015 #2
  4. Jan 29, 2015 #3
    Like suddenly a thought came to me of posting this question on PF. How it is coming to me, isn't that random?
    Dreams and thought might be different.
    But can we consider dreams as random thoughts?
    Like when I was sleeping a dream came of dogs biting me, in reality it has not happened.
    So dreams are kind of mixing our day to day things and creating random thoughts?
     
  5. Jan 29, 2015 #4

    Pythagorean

    User Avatar
    Gold Member

    I was reading about this a couple months ago and this thread reminded me of it. When your attention isn't focused on anything in particular, your brain gets increased activity in a region called the "default mode network". The paper I read (in nature neuroscience, I believe) went into how the modes themselves were functionally significant, so they could be involved in meandering thought processes. I can't currently find that paper, but here are some other related resources:

    The brain's default network: anatomy, function, and relevance to disease.
    http://www.ncbi.nlm.nih.gov/pubmed/18400922

    The brain's default network: anatomy, function, and relevance to disease.
    http://www.ncbi.nlm.nih.gov/pubmed/18400922

    Unrest at rest: Default activity and spontaneous network correlations
    http://www.sciencedirect.com/science/article/pii/S1053811907000079
     
  6. Jan 29, 2015 #5
    Thanks for giving a lot of material and links, find it useful.
    Just wanted to ask
     
  7. Jan 29, 2015 #6

    Pythagorean

    User Avatar
    Gold Member

    We're not really sure about dreams. Dreams pull from your memory pool (so you can't dream of a dog unless you've encountered one) but there's no obvious method in the way memories are pulled into dreams and put together. There are hypotheses proposing that dreams have something to do with memory coding. You can find them easily if you look for them, as it's a sensational claim (whether true or not) so I will not post them. I will instead post evidence that suggests that dream-relevant memory coding doesn't rely on sleep [1] - well, not anymore than vital function does, and I guess that's the issue. It's a lot like arguing that oxygen is important to memory because if we don't have oxygen we die and dead people don't form memories. True, but not very useful for understanding the mechanism and potential function of dreams. So, ultimately, we need to have a clear, synthesized picture of all the processes involved. The brain is a complicated system, so instead we just have a lot of studies focusing on particular regions, particular dynamics, and particular environmental considerations. Memory is already a complicated subject - there's different kinds of memory and different brain regions associated with them and two kinds of memory can work together to form a third kind of memory (episodic and procedural memories can inform semantic memories). Further, there's always a bit of rewriting in memory recall (reconsolidation [2]) so are dreams just doing some memory writing in the usual way as with any memory recall or are they actually doing some kind of optimization on our memories?

    I'm not making the argument that dreams don't have anything to do with memory, I'm fairly neutral on the subject, but I think that a basic literature search is bias towards the hypothesis that it does. So are dreams random? Maybe.

    [1] http://www.sciencedirect.com/science/article/pii/S0896627304005653
    [2] http://www.ncbi.nlm.nih.gov/books/NBK3905/
     
  8. Jan 29, 2015 #7
    Thanks for giving a detailed explanation. I will see the links some time later, though your para was descriptive and helpful.
     
  9. Jan 30, 2015 #8
    Random thoughts are likely generated in the "minds" of most if not all mammals in general. The real question is, what do these animals' minds do with them. The actual generation of random memories can occur spontaneously in any neural network. Energy flows throughout these networks heterogeneously in the absence of directed sensory stimuli and pseudo-randomly triggers cell-assembly attractors which generate potential thoughts via the radial spread of these excitations from their "sites of nucleation" in those cortical networks.

    In non-human animals, these potential triggers typically die out in the absence of an accompanying actual sensory stimulus to reinforce their representation in the cortical behavioral driving routines. In humans, on the other hand, there is considerable evidence that these chaotic anomalies can be be caught up in a higher system that can turn them into something other than decaying neural potentials. This something other may be the "random thoughts" you are asking about.

    This higher system has been identified as the Central Executive Network (CEN), and it is contrasted from the Default Mode Network (DMN) (that Pythagorean referred to above) as being the more phylogentically recent addition to the primate brain. In fact, there is a good argument that this network is unique to humans.

    http://www.pnas.org/content/104/43/17146.long
    http://www.ncbi.nlm.nih.gov/pubmed/25282602
     
  10. Jan 30, 2015 #9
    Thanks. Will look to it in detail in future as I'm not a biology student. Just had a interest in knowing these phenomena as there are many types of things in world to understand. I will now not be available frequently in this discussion. The others may continue their arguments and can debate among themselves.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook