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sophiaserpentiaHuman beings, as products of evolution, have not been engineered for maximum efficiency, but contain systems and faculties which came, over successive generations, to operate at varying degrees of sufficiency.
There is no true "hardware/software" distinction with the brain. It may turn out that the "hard dualists" are right, but otherwise, the mind and body are interlinked in a single system. Thoughts are made not of binary electrical signals (like circuits which are either on or off) but analog chemical signals conveyed by over 60 kinds of neurotransmitters and neuropeptides.
Learning involves actually changing the neural configuration of the brain, which is why children learn more quickly than adults -- the brain is much more plastic when people are young. Once a pattern is established, it is difficult or impossible to change, because changing it involves destroying some neural connections and growing other new ones. This is why for example we have thoughts or behaviors which we know are less than efficient but which we have difficulty changing. Some people are more capable than others of achieving this change.
Nervous systems are not made up of "general-purpose circuitry" -- IOW, one nerve or node is not as good as another for a given purpose. Generally speaking, each faculty in the nervous system developed piecemeal in response to a given need.
It is only because of accidental flexibility that certain pieces of the brain can be used for "higher" kinds of thought. A lot of our abstract thought, for example, occurs in the motor regions of the brain, because at its root, abstract thought is contemplation of actions we have to take (even if that action consists of engaging the vocal system in order to speak).
Much of our cognition occurs via various 'inference systems' which serve mainly to minimize the amount of effort required to analyze a given stimulus and formulate a response. These systems operate at different degrees of urgency and have different levels of dominance. For example, the predator-detection inference system is capable of grabbing the mind's attention away from whatever else it may be doing -- because this is what needs to happen. My recent comments about predisposition for certain kinds of thought and cultural pattern touch on this.
It is sometimes very difficult for the mind to "see around" the cognitive shortcuts taken by inference systems. My recent comments about gender essentialism reflect this observation.
The brain is a parallel processor. Each stimulus is examined by several different pieces of the brain at the same time. For example, when someone is speaking to you and using hand gestures, a special part of your brain hears the sound and routes it to the language parser; non-verbal cues are interpreted by another special part of the brain which handles the social relevance of what the person is saying; and a special motor part of your brain figures out what the hand motions look like from the other person's perspective and works out how to imitate them and provides some input on what meaning these gestures convey.
Different parts of the brain are capable of handling contradictory information at once. For example, one inference system might conclude that the person to your left is a man, while another might conclude that person is a woman. What usually happens is that there is a brief period of cognitive dissonance while these thoughts compete for dominance.
The conscious mind is very clearly not in "control" of most of the brain and is not even aware of most of what is going on. The conscious mind is capable in fact of being mistaken about what the brain is actually doing. A possible explanation is that conscious thought is a largely memetic faculty which has been hobbled together as a barely-sufficient response to the challenges of civilization.
There is no true "hardware/software" distinction with the brain. It may turn out that the "hard dualists" are right, but otherwise, the mind and body are interlinked in a single system. Thoughts are made not of binary electrical signals (like circuits which are either on or off) but analog chemical signals conveyed by over 60 kinds of neurotransmitters and neuropeptides.
Learning involves actually changing the neural configuration of the brain, which is why children learn more quickly than adults -- the brain is much more plastic when people are young. Once a pattern is established, it is difficult or impossible to change, because changing it involves destroying some neural connections and growing other new ones. This is why for example we have thoughts or behaviors which we know are less than efficient but which we have difficulty changing. Some people are more capable than others of achieving this change.
Nervous systems are not made up of "general-purpose circuitry" -- IOW, one nerve or node is not as good as another for a given purpose. Generally speaking, each faculty in the nervous system developed piecemeal in response to a given need.
It is only because of accidental flexibility that certain pieces of the brain can be used for "higher" kinds of thought. A lot of our abstract thought, for example, occurs in the motor regions of the brain, because at its root, abstract thought is contemplation of actions we have to take (even if that action consists of engaging the vocal system in order to speak).
Much of our cognition occurs via various 'inference systems' which serve mainly to minimize the amount of effort required to analyze a given stimulus and formulate a response. These systems operate at different degrees of urgency and have different levels of dominance. For example, the predator-detection inference system is capable of grabbing the mind's attention away from whatever else it may be doing -- because this is what needs to happen. My recent comments about predisposition for certain kinds of thought and cultural pattern touch on this.
It is sometimes very difficult for the mind to "see around" the cognitive shortcuts taken by inference systems. My recent comments about gender essentialism reflect this observation.
The brain is a parallel processor. Each stimulus is examined by several different pieces of the brain at the same time. For example, when someone is speaking to you and using hand gestures, a special part of your brain hears the sound and routes it to the language parser; non-verbal cues are interpreted by another special part of the brain which handles the social relevance of what the person is saying; and a special motor part of your brain figures out what the hand motions look like from the other person's perspective and works out how to imitate them and provides some input on what meaning these gestures convey.
Different parts of the brain are capable of handling contradictory information at once. For example, one inference system might conclude that the person to your left is a man, while another might conclude that person is a woman. What usually happens is that there is a brief period of cognitive dissonance while these thoughts compete for dominance.
The conscious mind is very clearly not in "control" of most of the brain and is not even aware of most of what is going on. The conscious mind is capable in fact of being mistaken about what the brain is actually doing. A possible explanation is that conscious thought is a largely memetic faculty which has been hobbled together as a barely-sufficient response to the challenges of civilization.
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no subject
Date: 2005-04-19 05:26 pm (UTC)because changing it involves destroying some neural connections and growing other new ones.
I haven't understood such changes to so much be about destroying connections as making new ones. It has been my understanding that the brain relies on making new interconnections amongst existing neural pathways.
no subject
Date: 2005-04-19 06:00 pm (UTC)I am a materialist, but not a reductionist, if you can grok that. I described my speculations on the matter here:
http://www.livejournal.com/users/sophiaserpentia/516619.html
I find that people operate under dualistic ideas about "the mind" being essentially software, and therefore ephemeral and easily changed. This belies the reality of everyday existence (and explains for example why people can be so intractible, even when they *want* to change; or why repressed memories cannot be consciously recalled even though they have a stealth affect on actions and feelings). This is in turn a result of the fact that mind is often mistaken about what is going on in the body and brain.
For me the beauty of this way of thinking is the elegance and explanatory power it has: many of the odd vagueries of human behavior can be explained by appeal to this idea, and many ideas can be tested this way.
no subject
Date: 2005-04-19 08:55 pm (UTC)This is an aside, but it could be an interesting topic anyway: at the level of a single cell, neurotransmitter release is typically binary; although the fact that summation processes occur across the functioning of many cells does give the overall system an analog character. But there is also direct ionic (electrochemical) connections between neurons that are unmediated by neurotransmitters, and there we see true analog functioning.
"Once a pattern is established, it is difficult or impossible to change, because changing it involves destroying some neural connections and growing other new ones."
I don't think the destruction/growth of neural connections is much of a limiting factor: it results from changes in dendrites rather than entire cells, and occurs at a rapid pace. Pattern changing is difficult for two general and closely reasons: firstly, patterns become overdetermined with increasing activation; secondly, there is a progressive physiological conservatism which biases established patterns. Adult physiology "assumes" that any patterns it has well-established are so because they are successful, and so is "hesitant" to change them (to anthropomorphize a bit).
"Nervous systems are not made up of 'general-purpose circuitry' -- IOW, one nerve or node is not as good as another for a given purpose."
Sort of -- a nerve in itself is general-purpose. This is why we see things like children with hemispherectomies having surprisingly unimpaired psychological development -- there's nothing fundamental associating any neuron with any function. However, the specificity you refer to does develop -- as a result of the connections a neuron makes with others, and the issues described above. As a 'parallel-distributed-processing' system, the meaningfulness of the brain's circuitry is in these patterns of interconnection, rather than neurons or nodes themselves.
"Different parts of the brain are capable of handling contradictory information at once... What usually happens is that there is a brief period of cognitive dissonance while these thoughts compete for dominance."
Theorists (principally Gazzaniga) have theorized an 'interpreter module' which creates narratives to account for contradictory information (and may also be universal -- creating narratives out of non-contradictory information as well). This was investigated in split-brain patients, where one of the isolated hemispheres is asked to explain behavior prompted by the other. Rather than accept the situation that it is unaware of why its body is doing something, the ignorant hemisphere develops a delusional belief in order to account for it.
no subject
Date: 2005-04-19 09:23 pm (UTC)no subject
Date: 2005-04-19 10:13 pm (UTC)Here are some articles by Gazzaniga on the topic: Automatic Brains -- Interpretive Minds (http://gnosia.tripod.com/gazz.pdf) (pdf) from Current Directions in Psychological Science, and The Split Brain Revisited (http://gnosia.tripod.com/gazz.htm) (htm) from Scientific American.
no subject
Date: 2005-04-19 11:43 pm (UTC)no subject
Date: 2005-04-19 09:18 pm (UTC)I am by no means an expert here, but the speed at which neurans can grow is limited by the availability of the building blocks. Modern civilized humans eat a huge amount of omega 6 oils, and hardly any omega 3 oils -- which is the exact opposite of our primative ancestors. Guess which is needed for making neurons? Omega 3. So our primative ancestors probably learned faster throughout their whole lives than modern humans.
I have been taking both flaxseed oil and cod liver oil daily, and have gotten rid of most all other veggie oils to reverse this high omega 6 dietary trend.
It seems to me I am able to change my habits more quickly. Could be a self-delusion, but I don't think so.
no subject
Date: 2005-04-20 01:38 pm (UTC)I always wanted to say that I'm very flattered you friended my journal. I hope you find some of the thoughts comment-worthy.
no subject
Date: 2005-04-21 02:42 pm (UTC)Apologies for not commenting on your posts... it is difficult for me to keep up with this journal, my life, and my friend's list, and so I do not always put in the kind of attention I would like to other people's posts.
no subject
Date: 2005-04-22 01:15 pm (UTC)I can DEFINITELY identify with that. I don't even have internet at my house. It's only because I don't have a job that I have enough time to write so many entries as I do, and to check the internet when I can. We will see what happens when I get work.