Skip to main content

An engineering analog for the function of astrocytes and their implication in attentional awareness: A theory

A few days ago I was thinking about our brains amazing ability to switch focus on features within an incoming sensory data stream. It has always fascinated me when I probed it in a biological mind frame but I realized this morning after waking a new idea that may explain how attention is performed in the brain.

The idea inspires this article now after I read a post by a friend on Facebook regarding the startled behavior of his cat when ever he takes the vacuum cleaner out of the closet. I realized in that example how my dream could explain its behavior. I assert that when we finally understand the mammalian brain fully we'll be able to prove that the cats brain has an unusually long attentional neuronal pathway.

Recent research in the area of explaining how mammalian brains switch attention seems to implicate a critical role for glial cells in the process of allowing us to keep our attention on certain things in each of our sensory dimensions....for example, your ability to tune in to a horn while listening to a jazz band or to focus on your mothers face in a crowd photo of many moving faces.

In all kinds of systems design including software systems design we do this using buffers, by trickling a bit of the data into a buffer you allow it to persist in a memory space so that the deeper brain can get to work processing  sensory data in the buffer while the sensation continues to come in (but not be processed since the cognitive load is focused on the data in the "buffer") at real time.

I posit that buffering is critical to reducing apparent execution time of the entire processing act, when you don't have buffering sudden influx of information can get lost as what happens in a video stream that doesn't have buffering enabled, all of a sudden it is susceptible to network latency.

The cognitive equivalent of network latency in a cat brain is that in its perception sudden events seem to appear out of now where and make for shocking occurrences. No causal connection is made between some new event and a previous temporal chain and thus the mind is more prone to being startled by fast changes in the incoming sensory data stream. I think this points to the core possible difference between a cat brain and say a human brain when it comes to attention.

We know that cats are exquisitely patient animals, they can get "locked in" on all types of sensor experiences...smells, tastes, vision...all seem to lock a cat into a trance....well if attentional awareness using glial cells (astrocytes in particular)  is indeed the brains global buffering system then an explanation for the cat brain I can think of is that it has a very deep (as opposed to shallow) buffer.

A deep buffer allows a good bit of data to be stored for attentional processing of some important feature in that captured stream and be compared to inborn salience factors BUT it also means that the cognitive load on that buffered data is higher (it's processing more data) meanwhile the incoming sensory flood by passes the buffer (the cat is not aware of it) thus having a deep buffer provides the advantage of being able to closely monitor discovered salience features (like focusing on the movement of a rat through tall grass) in the buffered data but has the disadvantage of losing large blocks of incoming sensory experience data that is not the subject of focus (attention)...this could perceptually translate to the seemingly perpetually shocked behavior patterns of cats when it comes to all manner of incoming sensory data.

In contrast to the cat other animals have different attentional "buffering", with some animals having almost no buffer in which case hiccups in perception are common, the animal playing back experience as if everything is new (like insects) in fact insects have a secondary system of attention that is completely external to their brain...that is the chemical signaling systems they've developed to guide behavior. At the other extreme are humans who in contrast to Cat's have a shorter buffer but as mammals have buffers way longer than a Lizard whose buffer is way longer than the aforementioned insects.

This theory could be falsified in several ways. If astrocytes are a common factor in attentional awareness some hypothesis can be tested:

1) Insect brains should be found to have significantly lower ratios of glial to neuronal cells.

2) Cat brains and the brains of other mammals with excellent ability to focus for long periods of time (usually for purpose of predation) will be found to have longer attentional buffering systems than humans.

3) Humans will fall some where between Cats and Reptiles...and Reptiles will be above Frogs which will be above Fish...which will also likely have greater attention than insects.

4) There is no reason for buffering to be the same depth in all brain regions...for visual stimuli some species may have a deeper buffer (more astrocytes as a percentage of neurons), for auditory stimuli other species (say bats) may have a deeper buffer to be "cat like" when it come to sound. Such variations would be expected to correlate along these sensory correlated behavioral lines. The general trend discovered is that there should be a correlation with the number of astrocytes in the regions of the brains of species that have a specialization that relies on a given sense in a dominant fashion (as cats do with their eyes and ears and less so their noses).

Links:

http://web.mit.edu/newsoffice/2012/neuroscientists-shed-light-on-plasticity-0927.html

http://www.urmc.rochester.edu/news/story/index.cfm?id=3452

http://learn.genetics.utah.edu/content/addiction/reward/cells.html

Comments

Healy said…
Ok, wow, did not expect Henry cat's hatred f the vacuum cleaner to inspire this kind of a deep post! :)

Popular posts from this blog

the attributes of web 3.0...

As the US economy continues to suffer the doldrums of stagnant investment in many industries, belt tightening budgets in many of the largest cities and continuous rounds of lay offs at some of the oldest of corporations, it is little comfort to those suffering through economic problems that what is happening now, has happened before. True, the severity of the downturn might have been different but the common factors of people and businesses being forced to do more with less is the theme of the times. Like environmental shocks to an ecosystem, stresses to the economic system lead to people hunkering down to last the storm, but it is instructive to realize that during the storm, all that idle time in the shelter affords people the ability to solve previous or existing problems. Likewise, economic downturns enable enterprising individuals and corporations the ability to make bold decisions with regard to marketing , sales or product focus that can lead to incredible gains as the economic

How many cofactors for inducing expression of every cell type?

Another revolution in iPSC technology announced: "Also known as iPS cells, these cells can become virtually any cell type in the human body -- just like embryonic stem cells. Then last year, Gladstone Senior Investigator Sheng Ding, PhD, announced that he had used a combination of small molecules and genetic factors to transform skin cells directly into neural stem cells. Today, Dr. Huang takes a new tack by using one genetic factor -- Sox2 -- to directly reprogram one cell type into another without reverting to the pluripotent state." -- So the method invented by Yamanaka is now refined to rely only 1 cofactor and b) directly generate the target cell type from the source cell type (skin to neuron) without the stem like intermediate stage.  It also mentions that oncogenic triggering was eliminated in their testing. Now comparative methods can be used to discover other types...the question is..is Sox2 critical for all types? It may be that skin to neuron relies on Sox2

AgilEntity Architecture: Action Oriented Workflow

Permissions, fine grained versus management headache The usual method for determining which users can perform a given function on a given object in a managed system, employs providing those Users with specific access rights via the use of permissions. Often these permissions are also able to be granted to collections called Groups, to which Users are added. The combination of Permissions and Groups provides the ability to provide as atomic a dissemination of rights across the User space as possible. However, this granularity comes at the price of reduced efficiency for managing the created permissions and more importantly the Groups that collect Users designated to perform sets of actions. Essentially the Groups serve as access control lists in many systems, which for the variable and often changing environment of business applications means a need to constantly update the ACL’s (groups) in order to add or remove individuals based on their ability to perform cert