Earlier this week, I wondered if all of our new knowledge about the brain, which is too often presented in a lazy causal fashion - if x lights up, then we do y - might undermine our sense of self and self-control. I've since riffled through the literature and found some interesting and suggestive answers.
The first study was done by Kathleen Vohs and Jonathan Schooler. The experiment itself was simple: a group of undergraduates was given two excerpts from Francis Crick's The Astonishing Hypothesis. The first excerpt espoused a fiercely deterministic and reductionist view of the brain:
You, your joys and your sorrows, your memories and your ambitions, your sense of personal identity and free will, are in fact no more than the behavior of a vast assembly of nerve cells and their associated molecules. Who you are is nothing but a pack of neurons.
The second excerpt discussed consciousness but didn't mention free will. After reading these passages, the students were quizzed about their free-will beliefs, and given a seemingly unrelated activity that involved arithmetic problems. Here is Schooler describing the setup:
Participants were told that there was a glitch in the software program [that administered the test] and that after the problem was presented, they needed to press the space bar in order to prevent the computer from inadvertently giving them the answer before they had solved it themselves. Furthermore, participants were told that although the experimenter would not know whether they had pressed the space bar, they should try to solve the problems honestly on their own. In short, a failure to press the space bar enabled them to get the answer without solving it themselves, in effect, to cheat.
Clever, no? It turned out that students who had read the anti-free will quote were significantly more likely to cheat on the mental arithmetic test; their exposure to some basic scientific spin - your soul is a piece of meat - led to an increase in amorality. Of course, this is a relatively mild ethical lapse - as Schooler notes, "None of the participants exposed to the anti-free will message assaulted the experimenter or ran off with the payment kitty" - but it still demonstrates that even seemingly banal materialist concepts can alter our ethical behavior.
Another study, led by Roy Baumeister and colleagues, looked at how a "disbelief in free will" could increase aggression and reduce prosocial behavior. One group of students was told to read statements that were supposed to induce a feeling of determinism, such as: "'Ultimately, we are biological computers - designed by evolution, built through genetics, and programmed by the environment.'" The second group, in contrast, was given sentences designed to bolster a belief in free will: "I am able to override the genetic and environmental factors that sometimes influence my behavior." A third group - the controls - were given neutral statements.
The students were then given hypothetical scenarios in which they quizzed about their willingness to help others, such as giving money to a homeless person. You can probably guess the punchline: students who had read the anti-free will sentiments reported being significantly less likely to help out in. No differences were found on either helpfulness or belief in free will between the control and pro-free will participants, suggesting that our pre-existing views are generally pro-free will.
The second Baumeister experiment left the hypotheticals behind. The subjects were assessed for their belief in free will and then told about a fellow student whose parents had been killed in a car accident. This student was going to have to drop out of school unless she could find someone to help her out financially. The students were then given the opportunity to help her out. Sure enough, disbelief in free will was associated with a reduced willingness to help.
Lastly, students were given the opportunity to add varying amount of hot sauce to food that would be eaten by a student who didn't like spicy food. Not surprisingly, those who read the anti-free will statements added more hot sauce.
At the very least, free will is a useful illusion, leading us to be more prosocial and ethical. Because even if we are just "a vast assembly of nerve cells and their associated molecules," we're a vast assembly that feels like so much more. William James, as usual, said it best: "My first act of free will shall be to believe in free will."
Brain & Behavior
Comments (92)
I think that there is too much focus on an either/or scenario. The brain is a very complex system and I think it might be better compared to as a probabilistic determinism. In other words, we are inclined to behave in certain ways as responses to stimuli. We have an inclination to believe we are free-independent entities because it serves us well the vast majority of the time.
Posted by: pjtexas | December 17, 2009 1:12 PM