Biological Determinism & Plasticity

[Energystrom]

A thought popped into my head today regarding biological determinism and possible consequences of such, and more specifically, how plasticity of the brain plays some role in this.

Many purport that once we reach a great enough level of expertise in the natural sciences--specifically biology--we will understand enough of the human body/brain to demonstrate that we are essentially biologically determined. I here use "biologically determined" in the sense that we do not have free will in any true sense, but rather, we are naturalistically conditioned such that we are compelled to act as we do. Basically, biological determinism would have us understand that our actions arise from biological states, not from a conscious judgment or determination of will.

(Correct me if I'm wrong on the following portion, my knowledge of neuroscience is basic.)

We also know that the brain is "plastic." That is, when we recall memories, or store facts/etc, we actually change the structure of our brain. (Plasticity is also often used in the occasion of damage to the brain and its subsequent restructuring.) We form new synapses, connect clusters of thoughts, etc. This would seem to entail that the mind-brain relationship is not a one way flow from brain-->mind, but rather, simply THINKING can physically reciprocate, changing how our brain actually works.

If this is the case, then in some sense, doesn't this notion vitiate biological determinism?

Even if one argues that we do not have COMPLETE freedom because we are initially biologically conditioned, at the very least we are still given the ability to formatively change our physical structure based upon our conscious thoughts. We can change our character/etc and shape the way we act in some fundamental sense. So at least in this regard, a qualified freedom of will would endure.

 

[Pythagorean]

If by "biologically determined" you mean "genetically determined" then that is not the prevailing view. Robert Sapolsky (one of the US's leading neuroethologists) makes this point clear in his lectures and presentations (see "The Genetic Myth" for instance).

So the other half of the story is stimulus (i.e. environment). Without the proper environment, abiogenesis would never have taken place in the first place. Evolution itself is the about the story of how selection (environmental driving) shapes genetics.

Determinisn and Plasticity:
Plasticity does not unseat determinism since plasticity happens as a result of stimuli. Stimuli and classical biology are modeled deterministically, so plasticity can be modeled as a deterministic process in which a signal acts on your receptors, and the interneural network responds accordingly in a way such that you would (for instance) increase dopaminergic response the next time (or decrease the chance of a decrease in dopaminergic response).

Free will and determinism:
Unless you want to bring a soul into it, if you accept determinism, then you must accept that we don't have some magical free-will. We are products of nature just like everything else. But a determinant universe isn't something that's been measured or discovered. In fact, Prigogine makes many arguments against determinism in chemistry (through dissipative system).

opinion:
I take the determinist assumption because deterministic models have been successful for me. I don't take the stance that determinism must be, but it's a valid working assumption. It's not particularly disconcerting to me to not have "free will". I'm not a fatalist, so it doesn't mean, to me, that I should just sit down and die. It means that learning and spreading information laterally to my society will inform them and give them a better place to make decisions from. Even if those decisions are deterministic, we still get to enjoy the subjective experience of making the decisions.

 

[Energystrom]

Thanks for the thoughtful reply.

If by "biologically determined" you mean "genetically determined" then that is not the prevailing view. Robert Sapolsky (one of the US's leading neuroethologists) makes this point clear in his lectures and presentations (see "The Genetic Myth" for instance).

So the other half of the story is stimulus (i.e. environment). Without the proper environment, abiogenesis would never have taken place in the first place. Evolution itself is the about the story of how selection (environmental driving) shapes genetics.

I wasn't specifically referring to the nature vs. nurture argument.

What I mean is more along the lines of determinism of action of an individual.

For example: with sufficient understanding of an individual's chemistry, one might predict how an individual would respond to given scenario [x] or [y]. If biology reaches the point when an individual's actions in scenario [x] or [y] can be predicted with a high degree of regularity, then this would suggest that there is no true free will in action, but rather, we are governed by not-very-well-understood impulses out of our control.

Determinisn and Plasticity:
Plasticity does not unseat determinism since plasticity happens as a result of stimuli. Stimuli and classical biology are modeled deterministically, so plasticity can be modeled as a deterministic process in which a signal acts on your receptors, and the interneural network responds accordingly in a way such that you would (for instance) increase dopaminergic response the next time (or decrease the chance of a decrease in dopaminergic response)

If we posit that each individual will reflect differently upon scenario [x]'s occurrence, and that this reflection changes the composition of the brain (i.e. plasticity) such that he will act differently when faced with situations associated with scenario [x], then has the individual not in some way "changed" what would have otherwise been a deterministic unfolding of events?

Yes, one might respond that the initial reflection upon scenario [x] was determined as well, and conditioned in the first place so that the individual has not had the autonomous ability to shape himself, but in SOME sense, hasn't he "altered" the very substrate that theoretically determines him, thereby enacting a somewhat "free" action? While I would not argue against the fact that, in the whole, we are conditioned somewhat deterministically by experiences given in sense perception, the ability to alter our brain seems to be a feedback loop that at the very least gives rise to a QUALIFIED sense of free will, even if it can be traced back as empirically conditioned.

opinion:
I take the determinist assumption because deterministic models have been successful for me. I don't take the stance that determinism must be, but it's a valid working assumption. It's not particularly disconcerting to me to not have "free will". I'm not a fatalist, so it doesn't mean, to me, that I should just sit down and die. It means that learning and spreading information laterally to my society will inform them and give them a better place to make decisions from. Even if those decisions are deterministic, we still get to enjoy the subjective experience of making the decisions.

This is generally the case with discussions of free will. Even if you discovered that you were absolutely determined by conditions beyond your conscious understanding, it wouldn't particularly vitiate your "feeling" of free will. I won't leave this conversation deploring the fact that I am determined, because, quite simply, I still FEEL like I can choose between a Grande or Venti coffee at Starbucks.

Even so, the conversation is in itself fruitful if one desires a pursuit of knowledge.

 

[apeiron]

simply THINKING can physically reciprocate, changing how our brain actually works.

You are talking about determinism vs plasticity. But it would probably make more sense to talk in the more standard dichotomy of stability~plasticity (the neuroscience version of stasis~flux in classical metaphysics).

So the brain is hierarchically organised (in time as well as space). It has to be able to adapt and change, but not so quickly or easily that it becomes destablised and forgetful.

If you are interested, google Stephen Grossberg on the stability-plasticity dilemma and the catastrophic forgetting problem in neural network models for a good introduction to the issue.

So yes, thinking does rewrite the brain's structure. But in a balanced fashion. The brain is designed to generally do things according to learned habits (according to its stable structure) but also to at the same time learn new things (its plastic adaptations, its learning through the eye of attention).

There is no logical paradox here because stability is a relative concept, and so is plastic. In Grossberg's models, he indeed shows how they are the same thing over different spatiotemporal scales (that is why his is a hierarchical/systems approach). A mental habit may seem to be very stable, very deterministic (ie: constraining on your actions). But viewed over a developmental timescale, it is highly plastic.

Before you learned to drive a car, your actions behind the steering wheel for the first time would have been so unconstrained, so novel, as to have been alarming "random" I would bet. And completely draining on your attention. But after a few years, it would be second nature, unthinking. A stable brain habit.

 

[Pythagorean]

Yes, one might respond that the initial reflection upon scenario [x] was determined as well, and conditioned in the first place so that the individual has not had the autonomous ability to shape himself, but in SOME sense, hasn't he "altered" the very substrate that theoretically determines him, thereby enacting a somewhat "free" action? While I would not argue against the fact that, in the whole, we are conditioned somewhat deterministically by experiences given in sense perception, the ability to alter our brain seems to be a feedback loop that at the very least gives rise to a QUALIFIED sense of free will, even if it can be traced back as empirically conditioned.

But we don't really have the ability to alter our brain absent of external stimuli. But yes, we do have a sense of free will, but i prefer to call it willpower to differentiate it from the idea that something magically happens without cause/effect. Willpower is a matter of cause and effect (for instance, one part of your brain inhibits another because it knows from experience that the behavior, while it can be rewarding, is usually not. Or another example: some people call willpower when an organism makes it through an unlikely environment.)

quite simply, I still FEEL like I can choose between a Grande or Venti coffee at Starbucks.

Even so, the conversation is in itself fruitful if one desires a pursuit of knowledge.

But don't you think it would be interesting if you could find a chemical and stimuli-history basis for why you choose what you do? Then you could understand yourself better and make decisions better. As an animal, once you see a path to a more stable positive response from the universe, you take it. For some people, caught up in their world-view, that could be a life of drugs. For others, it could be saving money until your older. For some, it's a particular career choice.