Tuesday, August 13, 2013

Quantum level randomness and freedom



In a blog post about a theorized quantum-level neural basis for free will, we have a couple of things to note.

First:
[R]esearch in John-Dylan Haynes’s lab at the Bernstein Center for Computational Neuroscience in Berlin, Germany has shown that an upcoming decision being made by human volunteers can be predicted from brain scanning data, at levels better than chance, up to 10 seconds before the volunteers know what they themselves are going to decide. So unconscious processes are thus actually in control your decision making long before you even know you’re making a decision.
Whoa! So that’s it, we’re done, there is no free will, right? The universe can’t sustain it, your brain has made up its mind before you have, and you have merely experienced the illusion that you’ve been in control since the moment you learned to crawl and discovered the feeling of agency.
Alright, hold up on that inferential train there parder. Let’s take a closer look: Say I decide to eat one of those delicious Voortman peanut butter wafers. I act. 10 seconds earlier, folks looking at a brain scan, and able to interpret its results in terms of intentions, were able to tell that I would so act, 10 seconds hence. So, there is a neural event the conscious upstart of which is what I take to be my free choice. This neural event is ‘behind’ the conscious event, causing it. Now, if that neural event is, in addition to being causally connected, actually identical with my making a choice, then my making a choice is behind my conscious experience of making a choice. So what? Why all the hand waving?

Aside from the oddity of the choice being time delayed in its being experienced first person, does this in any way detract from its being a choice; a free volition? Only if you assume that the free choice must, at every stage of its unfolding, be a fully conscious experience.

Every day is full of what sure seem to be free choices and attendant actions most components of which are not conscious, some of which are. I choose to walk, and undertake the action. Most of that is not conscious. In fact the only painfully conscious and deliberate walkers are those learning to do so (babies or folks that are undergoing rehab for instance). Does it follow from the fact that a lot of what is going on is not conscious that it is un-free activity? There is a missing link here.

Second thing to note - The post continues:
Not so fast. Enter Dartmouth neuroscientist Peter Tse, who has found a middle ground in his new book “The Neural Correlates of Free Will: Critical Causation” (MIT Press). Tse has thought through this enormous problem and realized something important that brings free will back to the realm of the living. Remember that determinism is an unavoidable fact of the universe at the macroscopic but not the quantum level. Well what if the macroscopic universe is not deterministic because the brain is designed to amplify quantum level particle effects to the macroscopic level through the action of specialized neuronal channels that make decisions potentially truly stochastic?
Please note: Stochastic = Having a random element.

This is an old saw but, one of these is not like the others. See if you can find it:

1. I choose to eat the wafer, and my arm moves to grab it.
2. I choose to throw the wafer away, and my arm moves to grab it.
3. My arm just suddenly moves toward the wafer where just a second ago, it was just hanging there.

Which one do you suppose is stochastic or random? The post continues:
There are chemical receptors on most neurons that receive neurotransmitters (globs of chemicals secreted by other neurons), that then respond by opening ion channels, causing neurons to create neutral [neural?] impulses (aka: macroscopic real world events normal people call “brain activity”, or “thought”). Well, in a deterministic universe… so what? You could have predicted every idea I’ve ever had, before my birth, if had enough data about the universe. Right? Tse says no, because some chemical receptors, called NMDA receptors, are actually blocked by a single atom of magnesium, that must first be released before ions can flow to cause brain activity. Because macroscopic brain activity is therefore dependent on the position of a single atom, which is itself a quantum-level creature, it means that these neurons amplify the quantum level activity of the magnesium atom to the level of neural circuit behavior and real life. Thus our behavior is indeed subject to quantum effects and the universe cannot be deterministic.
OK, my brain hurts. A single atom of magnesium acts as a sort of gatekeeper. If it steps out of the way, then neurotransmitters can do their stuff, the macroscopic result of which is gross motor movement, and presumably free choices that initiate such movement. But, because that single atom is small enough to be such that its state is significantly dependent upon quantum level randomness, then, whether or not it steps out of the way, and whether or not the macroscopic happenings occur is to a significant degree dependent upon the quantum state of that atom. Therefore, we have a neural correlate or cause of human freedom.

No: If stochastic/randomness is amplified, what you would have would be amplified or macroscopic randomness, NOT agency. While the mechanism described may make it the case that the macroscopic universe is not strictly deterministic, that does not make it the case that the randomness thereby generated equals free agency.

To use the three examples just above; this picture lends credence to #3, not # 1 or #2. Finally, our direct experience is in conflict with #3.

Why does talk of random bodily movement make me think of this?




 Betcha David Byrne took his magnesium supplements.