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The 2008 research findings of Soon et. al., gave the surprising result that when we are allowed time to make decisions, our subconscious neural networks make the decisions up to ten seconds before we are consciously aware of it.

Of course, there are many situations in which we act without seeming to make any conscious decisions at all. If an object is suddenly thrown at us, we may duck, dodge, deflect, hit, or catch it, the ‘choice’ seemingly being made in much less than a second. In such cases, the action seems involuntary and we assign it to instinct, which is just another name for the unconscious neural activity of our brains. The instinct to duck when an object is directed at our head or to withdraw our hands from a hot object is due to the neural system having developed shortcuts because of its obvious survival value and has been selected for over a long time in our evolutionary history. The part of the brain that codes instincts must necessarily act very quickly to give commands to the motor brain in response to stimuli from the environment. Certain stimuli trigger a stimulus-action connection that bypasses those sections of the brain that indulge in time-consuming activities such as processing information and making judgments.
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In a recent paper (Unconscious determinants of free decisions in the human brain, Chun Siong Soon, Marcel Brass, Hans-Jochen Heinze, & John-Dylan Haynes, Nature Neuroscience, vol. 11, no. 5, May 2008, 543-545), researchers used the more sophisticated modern technique of fMRI (functional magnetic resonance imaging) to measure brain activity. The paper is not available online without a subscription but you can read a news report on the results of their paper here.

This experiment was designed to meet two key concerns about the Libet studies: that the time interval between act and the precursor unconscious brain activity prior to act was too small to definitively rule out measurement errors, and that Libet’s team had not shown that the early brain activity was a predictor of a specific decision.

The fMRI studies find that our decisions as to what actions we will take originate in our unconscious neural activity and only later informs our conscious mind of it, thus providing strong evidence against the existence of free will. The paper describes what the researchers asked their test subjects to do while they were hooked up to fMRI measuring devices.
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The idea suggested by Benjamin Libet that what we call free will is not the popularly assumed ability to decide all our seemingly deliberate (as opposed to instinctive) actions but consists of the more limited ability to either let the predetermined action be completed or to veto it may be unsatisfying to some but its implications are worth exploring in case it turns out to be true. What this model says is that I have no control over what I decide to do in any given situation but I do have control over whether that decision is actually carried out. In other words, I cannot control my thoughts and decisions but I can control (within a limited range) my actions.
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People who are determined to keep the Ghost in the Machine alive still have a few options. Ironically, although it was Libet’s early experiments that cast doubt on the idea that we have free will, he himself was disturbed by that implication and has sought to find ways to salvage it. In his many publications, he repeats his belief that his experiments did not rule out free will and suggests ways in which it could still operate.
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In 1983, Benjamin Libet and his associates did some experiments that were similar to the 1963 Grey Walter experiment but with the added feature that the patients could observe the equivalent of a clock and thus note when they made the decision to act. This enabled a more objective determination of the time when they first had the conscious thought to carry out the action and not depend upon a possibly misleading feeling of surprise to infer the ordering of events.

One of the key original papers was published in the journal Brain (Time of conscious intention to act in relation to onset of cerebral activity (readiness-potential): The unconscious initiation of a freely voluntary act, vol.106, p. 623-642, 1983) which does not seem to be available online but you can read online a later review published by Libet in 1999 (Do we have free will?, Journal of Consciousness Studies, vol. 6, No. 8–9, 1999, pp. 47–57) where he summarizes his findings and its implications for free will.
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In post #6 in this series, I discussed the 1963 Grey Walter experiment in which patients who had electrodes implanted in their brain’s motor cortex that could send a signal to advance a slide were surprised that the projector seemed to anticipate their decision to advance the slide. Does this mean that their unconscious neural activity had decided to advance the slide before telling the conscious brain that it had decided to do so? If so, it seriously undermines the idea of free will. In his book Consciousness Explained (1991, p. 167) which discusses the experiment, Daniel Dennett warns that it is premature to accept this conclusion because it is based on the articulated sense of surprise reported by the patients, and the brain is not the most reliable of historians.
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In the previous post, I provided a schematic description of two models of how the brain works, one with free will and the other without it. The traditional brain model with free will is given by

(D)                                    GES
                                        ↓
will → conscious thoughts → unconscious neural activity → action

Our genes (G), environment (E), and the inherent randomness in the laws of nature (S) all contribute right up to the present instant to the brain’s structure and unconscious neural activity. But in this model, there is a separate branch in which our (uncaused) free will makes decisions first which manifests itself as a conscious thought. In this model there should be a definite temporal sequence in which the act of will occurs first, followed by conscious thoughts, then unconscious brain activity caused by that conscious thought, and finally the action.
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It is time to look at specific models of how the brain works.

In the previous post, I pointed to a paper by biologist Anthony Cashmore which argues that our brains are the product of genes (G), environment (E), and stochastic (i.e., random) processes (S). This GES combination influences the unconscious neural activity in our brains, which in turn gives instructions to the motor neurons that control our actions. So the causal and completely physiological chain goes like (A):

(A) GES → unconscious neural activity → action

The directions of the arrows signify the causal relationships. Our bodies are in a state of constant activity, with hearts beating, blood flowing, digesting food, breathing, secreting chemicals, producing new cells and disposing of old one, and so on, all of which take place without us being aware of it. I think everyone (except those religious people who can’t bear to see god not taking part in every single activity) will accept that our brains control and moderate all this unconscious behavior. What is in dispute is what gets added on to this basic model.
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The possibility of the existence of Lucretian random swerves that destroy determinism received a boost in the early twentieth century with the advent of quantum mechanics and its associated uncertainty principle that eliminated strict classical determinism.

Believers in free will seized on the inherent randomness built into these newly discovered laws of nature to argue that free will could exist and manifest itself at the quantum level. However, as our understanding of quantum mechanics has increased, few scientists seriously accept this possibility anymore because of the many problems such a model has. After all, random processes are, well, random, meaning that they are not subject to being controlled. If indeterminancy at the quantum level is what undermines determinism, what we would have is not free will but what we might call ‘random will’, in the sense that we would be acting according to the random outcomes of quantum level phenomena over which we have no control. Furthermore, while individual quantum events may be completely indeterminate, they do obey laws that enable us to accurately predict statistical outcomes, so these events cannot be truly free. Free will as popularly conceived does not consist of random or statistically predictable behavior but of the ability to deliberate and determine specific outcomes. No mechanism has been proposed to suggest how that might occur.
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Defining what is meant by free will is not easy. In a loose sense it implies a denial of strict determinism, in which all our actions are completely determined by the past and the immediate environment we find ourselves in. The philosopher John Searle describes free will as the belief “that we could often have done otherwise than we in fact did.” In other words, although I am currently sitting at my desk typing, I think I could just as easily stand up and sing or hop around the room or do any other seemingly spontaneous act. My decision to not do so and continue typing seems like a conscious, freely chosen decision that is not entirely pre-ordained. The catch is that it is hard to reject the alternative hypothesis that all the options I considered were already determined by my history and the external stimuli of the moment, as was also my decision as to which option to choose.
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