We have various ways of moving. Here are four obvious ways and there may be more. First, a spinal cord reflex happens without the involvement of the brain at all. We have no forewarning of it or way to stop it, but we can block it ahead of time by a sort of steeling against it example removing finger from burning heat. Second, there are inborn and learned patterns that we do without thinking but can do by decision example blinking. Third, there are well learned complex patterns that we are almost always aware of and can initiate but do not think about on a continuing basis example walking. Fourth, there are actions which we think about and decide to do decide to take the red one rather than the blue when offered a choice. As any action can result in a good, neutral or bad outcome, we need to know what kind of an action it was to know how to deal with the outcome.
What we need is the way to mark actions as one of: not ours, automatic, the result of our unconsidered decisions and the result of our considered decisions. We need to know what it was that caused the action. What is the involvement of consciousness in this marking? Our actions are committed to episodic memory with a sense of how the action came about. Do I ‘own’ this action? If someone bumps my elbow and therefore I move in a way that spills my drink, I do not own the spill; I did not do it. But if my muscles are moved by my body I own the movement. But I may not have intended it I sneezed and spilled the drink. I’m sorry but I didn’t do it on purpose. Or I forgot I had the drink in my hand I didn’t mean to do that, I was not paying attention and I should have been; sorry. Or I may have intended it putting out a fire or making a physical criticism of the quality of the wine.
For those actions were it is possible, what we register consciously is: an intention to act, followed by an initiation of an action, followed by the sensation of doing the action. It is reasonable (if we are naïve) to assume that the action is the result of the initiation which is the result of the intention. Not so. The way actions happen is different from the way they are marked in our conscious experience. We know this from three types of experiment.
The famous experiments of Libet (see citation) showed that the motor action was being prepared before the subject was aware consciously of his intent to act. Therefore the conscious intent could not be the cause of the action. This does not mean that there was no intent to act but just that the conscious awareness of intent was not the cause of the action, some sort of unconscious intent was the starting point.
Wegner’s experiments (see citation) showed that people will take ownership of actions that are not their or refuse ownership of actions that are theirs. If the timing is right between the subject thinking about some action and perceiving the action, if they could physically do the action and if there is no better agent for the action around, then they will feel they did it even if they have been manipulated by experimental tricks with priority, consistency and exclusivity. They can also reject having done something that they did by the same sort of manipulation in reverse. This means that what we experience is not knowledge of our motor actions but a cognitive judgments of what they must have been (in other words, good guessing).
Desmurget and his group (see citation) have done experiments on the relationship between action and the consciousness of action. They show that correlation is being confused with causation. The posterior parietal cortex does sensory predictions but not motor commands and if it is stimulated mildly the subject senses the intention to do something. A stronger stimulation gives the subject the illusion that the intended action is happening. But stimulation of the PPC does not result in any action at all only the conscious experience of the desire, initiation and execution but no actual movement. On the other hand stimulation of the premotor cortex results in a movement but no conscious awareness of intent or action. Without experimental direct stimulation, in ordinary life, these areas with others, produce a predictive conscious model of what is happening but the conscious experience is not causal definitely not causal. The conscious experience does mark the type of action in memory though and this is a useful function.
I wish that the freewill-v-determinism argument would go to some dark corner and die. We should forget both notions as not useful and concentrate on how and why our brains actually work. Consciousness can be extreme important to understanding and learning from our actions without actually being in the causal path. It marks the type of action in the episodic memory and it is the predictive model used to monitor action.
LIBET, B., GLEASON, C., WRIGHT, E., & PEARL, D. (1983). TIME OF CONSCIOUS INTENTION TO ACT IN RELATION TO ONSET OF CEREBRAL ACTIVITY (READINESS-POTENTIAL) Brain, 106 (3), 623-642 DOI: 10.1093/brain/106.3.623
Wegner, D., & Wheatley, T. (1999). Apparent mental causation: Sources of the experience of will. American Psychologist, 54 (7), 480-492 DOI: 10.1037//0003-066X.54.7.480
Desmurget, M., Reilly, K., Richard, N., Szathmari, A., Mottolese, C., & Sirigu, A. (2009). Movement Intention After Parietal Cortex Stimulation in Humans Science, 324 (5928), 811-813 DOI: 10.1126/science.1169896