Wednesday, January 12, 2011

Evolution of thoughts

People have their own thoughts on evolution, but does evolution also apply to their thoughts?  I don't mean the evolution of culture and ideas since the dawn of history (or before that, which is the subject of evolutionary psychology).  I mean within a single person whose subjective awareness forms their reality.  In that one person, when thoughts arise to the fore of the mind, what forces affect them and determine their fate?  Will they be forgotten?  Remembered?  How, why, and what are the possible implications?  Consciousness is only a small fraction of what our brain does, and a very fragile fraction at that. 

Last night I was nodding off to sleep as my daughter was reading me a bedtime story.  I had a thought, and considered writing it down but sleep overtook me.  When I awoke it was gone - another species of thought extinguished through the merciless action of natural selection within the confines of my mind.  Most animal species go extinct without leaving descendants, so too I imagine must thoughts. 


  1. I've had the same thought. Isn't that the idea behind memes (only focused on the population level rather than the individual level), that thoughts undergo a process similar to evolution in our minds?

  2. Yes, as you point out, memes are described as thoughts transmitted from one person or group of people to another. And selection forces, acting on the behaviors memes generate in their hosts, then determine which thoughts survive and which die out. But before any thought can even begin its journey as a meme, it must first pass through the gauntlet of the human brain.

  3. "But before any thought can even begin its journey as a meme, it must first pass through the gauntlet of the human brain."

    Well put. One thing I learned in a psychology class about human memory is that it appears to us that retrieving a memory (remembering/thinking) actually creates new memories. You could think of it as corrupting the source. Of course, it isn't clear exactly what a memory is in physical terms at this time AFAIK so it isn't clear to me what is being stored or modified/retrieved.

    Still, I think it is fun to speculate about how thoughts could undergo something akin to evolution at the physical level. We might see these memories going through a constant process of being cloned or even combined with other memories with errors under some kind of pressure and the original being destroyed in the process. Or we could find that memories, or the structures that contain them, are virulent and compete to plant the memory throughout the surroundings when activated (which could very well explain the feeling of wishing we could unsee something dreadful).

  4. For instance, see Ed Yong's write-up of how unconscious signalling during napping can increase memory strength/retention while waking recall can actually delete/warp memories.

    One idea Ed puts forth is that memories might have greater competition for retention while one is awake.