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Comment by jobigoud | Hacker News Reader

Your description almost matches an experiment done in EEG research called the Libet experiment [1], although it's a bit different than how you describe it I'm confident this is what you are referring to.

They find that when you perform an action, there is a EEG spike [2] in the motor cortex well before you actually consciously decide to perform the action. The experiment is conducted with a dot running around a circle and the subject has to tell when (as per where the dot was) he decided to act. The EEG potential is seen prior to that decision moment.

This is related to free-will as it is as if the decision of acting is not coming from your conscious self but from a deeper layer.

[1] Libet experiment: https://www.youtube.com/watch?v=OjCt-L0Ph5o

[2] Bereitschaftspotential: https://en.wikipedia.org/wiki/Bereitschaftspotential

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I remember hearing psych-major classmates discussing that experiment in the dorms after class. It's kinda mind-blowing when you think about it.

I read (in a book sitting in a science museum giftshop, so take with the appropriate grain of salt) that most of Freud's theories have been shown to be bullshit in the century and a half since he lived, but his enduring influence was showing that the vast majority of human behavior is unconscious. Instead of thinking of your consciousness as the primary actor that determines what you do, you have to think of it as a vague overseer that occasionally notices the body doing something and can intervene with enough time, exposure, and practice. And whole industries have been built upon that principle - advertising, mass media, propaganda, behavioral finance, therapy, coaching, education, gaming, gambling, cigarettes, coffee, travel, social media.

There was a HN thread 2 days ago about the rise and fall of scientific authority and how to bring it back. I cynically commented that the rise of the physical sciences came from the ability to win wars with them. You could look at the rise of the psychological and social sciences as coming from the ability to make money with them.

Wars are fought and won with psychology every day. Only fairly trivial “big army” wars are possible today.

Though Freud is often credited with coming up with the concept of the unconscious, it was actually quite well known before him.

Perhaps I'm missing the point here but why does this say anything about free will? Of course you can't make split second conscious decisions. But you've still made a conscious decision to prime your subconscious facilities to act in a certain way.

The consciousness is super slow. It doesn't make sense to have it "do" anything. But it's good for making executive decisions. The CEO doesn't make the product.

That's pretty much my line of thought. If I decide to bicycle somewhere, I'm certainly not consciously thinking through most of the act of actually cycling, but I have no doubt that the "uuugh, this is going to suck but I need the exercise" decision happened on a conscious level.

It meshes with certain other results, for example on timing of predictions (http://www.kurzweilai.net/more-evidence-that-youre-a-mindles...), and most interestingly on split-brain patients (http://www.powerofstories.com/our-brains-constantly-confabul...). In the latter case, split-brain people would make choices based on information only available to their right brain, then when asked to explain them would unconsciously invent an explanation for that choice which was based only on information from their left brain.

I'm not sure philosophically whether our inability to understand our decisions undermines our free will, but it certainly undermines any ability to consciously prime ourselves to make certain decisions - hard to have that feedback loop when you don't even know what decision you made!

Is saying it "meshes with specific other results" just a signal of cognitive bias?

I personally would confidently guess there are unconscious faculties in the mind, but I dont see how this experiment is remarkable in proving this, see here(1). Is it not an equally likely conclusion that the brain takes a few hundreds of a second to develop a conscious decision? Actually, the inverse of that is what would be remarkable.

1-https://goo.gl/images/MkT2PQ

The issue isn't whether a decision is unconscious or conscious. It's that we often think that we've made a conscious decision when the decision process we narrate for ourselves and others is provably impossible.

I should have phrased the original as "it is a relatively weak example of this specific set of experimental results".

> They find that when you perform an action, there is a EEG spike [2] in the motor cortex well before you actually consciously decide to perform the action.

No, that's not what they find. What they find is that the time of the change in EEG (it's not really a "spike", it's more like the leading edge of an increased action potential that lasts for a significant time) is a few tenths of a second before the time that the subject reports as the time they "made the decision". But you can't assume that the time the subject reports is "the time they made the decision", because the process of generating the conclusion "this is when I decided to act" also takes time--and that time was not measured. All you can really conclude from this experiment is that people are not consciously aware of all of the neural processes that actually go into their making a conscious decision.

Actually, this explains a feeling I've been having lately. In various occasions where I have to randomly pick between some things, I choose X but I can somehow feel that the actual choice happened a tiny fraction of a second before I was actually aware of it (kind of a contradiction, but I can't explain it better).

Basically, it feels like the decision was made a tiny bit earlier than "I" made it.

Why isn't the explanation that the reporting function is slow? Your "free will" -which we won't explain- decides to fire the motor neurons, and then does the reporting, which is pretty unnatural compared to moving a muscle, to do the thinking about where the dot was.

Or maybe you overcompensate when calculating where you thought the dot was.

The video addresses that. The experiments were constructed not so that you report "I decided to press the button", but rather by reporting "The state of the world [as measured by this rotating dot on the screen] was this at the time I decided to press the button." And he found that the state of the world that people reported when they pressed the button was consistently 200 ms before actually pressing the button (which is in accord with other experiments measuring human reaction time), but the EEG spike in the motor context were 350 ms before the subject's perception of reality at the time they made their decision, and 550ms before pressing the button.

Most people think of their consciousness as "That part of my mind which integrates all my sensory information into a coherent experience of reality at this moment, and then decides what to do within that reality." You could redefine free will as the EEG potentials themselves operating within your brain - but that's not how most people, subjectively, experience it, particularly because they are not generally aware of most of these EEG potentials directly.

I'm not going to pretend like I'm sat here on my couch and know more than those scientists, so can someone help me understand how they generated a free will hypothesis about this? Seems to me I could explain this with something like "short term memory assignment is delayed," i.e. the decision was made by the conscious brain, but the memory of making the decision had a long write time and therefore a later "timestamp."

I would submit this other similar experiment from YouTuber Vsauce [1] where a machine is trained to react to his subconscious thoughts before he consciously chooses to press a button.

[1] https://www.youtube.com/watch?v=lmI7NnMqwLQ Note: full video is behind YT Premium but the preview is enough to understand the experiment.

Isn't that easily explained by the time it takes to decide to speak after deciding to act?

Coming from a deeper layer does not mean it's not freewill.

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