Thursday, March 16, 2017

Thalamus Prediction

Concurrent Pattern Hierarchy

This is just a short post to make a quick prediction about the internal organization of the thalamus, a relatively small but complex area of the brain that is thought to serve primarily as a relay center between various sensors and the sensory cortex. Given my current understanding of the brain and intelligence, I predict that the parts of the thalamus that process sensory signals (e.g., the lateral and medial geniculate nuclei) will be found to be hierarchically organized. The function of the hierarchy is to discover small concurrent patterns in the sensory space. These are commonly called "spatial patterns" in neuroscience. I personally don't like the use of the word "spatial" to refer to patterns because I think it is misleading. All patterns are temporal in my view, even if they refer to visual patterns. Here are some of the characteristics of the thalamic pattern hierarchy as predicted by my current model:
  • The hierarchy consists of a huge number of pattern detectors organized as binary trees.
  • The bottom level of the hierarchy receives signals from sensors.
  • The hierarchy has precisely 10 levels. This means that the most complex patterns have 1024 inputs.
  • Every level in the hierarchy makes reciprocal connections with the first level of the cerebral cortex.
  • Every pattern detector receive recognition feedback signals from the first level of the cerebral cortex.
The cerebral cortex (sequence memory) can instantly stitch these elementary patterns to form much bigger entities of arbitrary complexity. A number of researchers in artificial general intelligence (AGI), such as Jeff Hawkins and Subutai Ahmad of Numenta, assume (incorrectly in my view) that both concurrent and sequential patterns are learned and detected in the cortical columns of the cerebral cortex. In my model of the cortex, the cortical columns are used exclusively for sequence learning and detection while concurrent patterns are learned and recognized by the thalamus.

Stay tuned.

Edit 3/16/2017, 2:42 PM:

I should have elaborated further on the binary tree analogy. I prefer to call it an inverse or upside-down binary tree. That is to say, each node (pattern detector) in the tree receives only two inputs from lower level nodes. Each node may send output signals to any number of higher level nodes. It is a binary tree in the sense that the number of inputs doubles every time one climbs up one level in the hierarchy.

1 comment:

Frank said...

The brain is not a computer. Theorists who reckon there are "centers" in the brain for processing, as say did Penfield, figure if they knew every stimulus input they'd be able to derive therefrom everything else, yields a lame deterministic theory because - there is that which is external to the organism - a spiritual essence that is divinely offered to each individual. Of course scientists, those who want to eliminate all talk of God, will forever be chasing their tails; Humans have advantage over other animals for their high intelligence, gifted to them so they can recognize a higher power and acknowledge gratitude by acting according to a moral code. The same lameness is true, say for heliocentrism, for example. The purpose of placing Earth dead center inside the spherical universe was to allow man to see he was placed there, in the center of it all, to bear a certain responsibility. Denying God leads to obfuscation and odd, weird concepts like the Big Bang, where the explosion must be from at least two elements combining or colliding, so already at least two things are at the "beginning". The crap physics has turned into, as you connote, comes because the scientist for some reason hates to admit he's significant, hates to think he has a higher calling. This is why stupid theories like evolution, earth being billions of years old or global warming derive, because introducing a Supreme power is anathema to the haughty secular scientist who "knows" there is no God. That human history, as far as history books and good archeology go, isn't more than 5 millennia, so they'll say back then, only 5000 years ago, humans were just runts ... The truth is hard for them to bear because it imposes a smatter of religion upon the person and to be free of all responsibilities and expected commitments man would rather swim a swamp of irrelevant facts.

I enjoy this site I happened upon. Will read more of it, to fathom physics a bit better. Glad you're a rebel. Probably you'll also disagree with what I said, for I have tried to wedge in more than a mouthful at the cost of clarity, but at least the rebel can better learn than he who is fanatically tied into the rigid structure of physicality, empty of spirituality - the key of humankind.