Our ability to exercise free will underpins many social and moral values and is ultimately what makes us responsible citizens and rational consumers. But advances in neuroscience are beginning to undermine the very concept of free will. Brain imaging techniques can now predict the choices that an individual will make long before they are themselves aware of making them. As more is understood about how the brain works, the mechanisms by which thoughts, decisions and actions are produced, the space in which free will could be said to operate is shrinking.
In the 1980s, Benjamin Libet and colleagues at the University of California in San Francisco took electroencephalograph (EEG) recordings of brain activity in study participants who were asked to make a free and spontaneous decision to press a button and recall the precise time at which they made their decision. Libet found that he could detect brain activity in the supplementary motor area (SMA) of the brain up to half a second before the participants were conscious of making the decision.
Variations of Libet’s study have been undertaken recently using more advanced techniques such as functional magnetic resonance imaging (fMRI) and recordings from individual brain cells. John-Dylan Haynes and colleagues at the Max Planck Institute for Human Cognitive and Brain Sciences asked study participants to choose between pressing two buttons – right or left – and were able to predict the participant’s choice up to 7 seconds before they were themselves aware of having made it, based on the pattern of brain activity detected on fMRI scans in the frontopolar cortex and precuneus brain regions.
Neurosurgeon Itzhak Fried and colleagues at the University of California in Los Angeles could predict the voluntary action of pressing a button up to 1.5 seconds before participants reported a conscious intention to act, from recordings of implanted electrodes in the brain that measure the activity of single brain cells. The electrodes were implanted throughout the brain as part of a surgical procedure for the treatment of epilepsy, and Fried found that brain activity in the SMA region of the brain predicted voluntary action.
During awake brain surgery, Michel Desmurget and colleagues at the University of Lyon found that stimulating the left inferior parietal brain region in patients produced a strong sensation of intention to move the lips and speak. Stimulating the left side produced urges to move the hand, arm or foot. When the intensity of stimulation to these areas was increased, patients reported that they believed they had spoken or moved, despite that no movement or muscle activity was detected.
Deciding to push a button is hardly equivalent to deciding who to elect, what career to follow, or even what to wear and whether to make a cup of tea. It is unlikely that these types of complex choices could be reliably predicted from brain scans. But what these studies demonstrate is that a complex pattern of brain activity involving specific brain regions precedes the conscious intention to act. Is it possible that more complex choices are also decided before we are consciously aware of them? Rather than controlling our thoughts and actions, consciousness may simply be a live-stream reporting of brain events that have already happened, too late to influence. It is difficult to imagine how free will could operate in such conditions.
Some everyday actions can begin to feel automatic: typing, driving, and so on. But that so much of the goings-on of our brain happen behind the scenes, unconscious and prior to our awareness, leaves us feeling uneasy and as though we are losing control of our bodies, simply machines or animals responding to external stimuli. The science seems increasingly at odds with our intuitive notion of free will, of ourselves as uncaused causers and responsible moral agents.
Intuitively, I perceive my mind as exercising free will, generating my thoughts and directing my actions. I experience a sense of intention, agency, and the ability to choose between several courses of action. But ‘me’ and ‘my mind’ may be just that: a perception, a sensation that emerges from the complex activity of the brain. My sense of free will, and my attribution of free will to others, may simply be an illusion hard-wired in the brain, a product of our evolution as social creatures.
The more that is understood about how the brain functions, the more of our psychology and behaviour that can be described through its physical processes, the less it is possible to conceive of a mind distinct from the body and brain. This new neuroscientific research forces us to acknowledge the extent to which the brain is just like any other organ, and cognitive activity just like any other bodily function, governed by the laws of physics, our genes and environment. Quantum mechanics, on the opposite end of the spectrum to this determinist perspective, offers no consolation; that our thoughts and actions might be determined by quantum randomness is equally unsettling and no closer to free will.
What does an eroding concept of free will mean for personal responsibility, justice and fair punishment? Already there are so many ways in which we accept that free will might be compromised in individuals, holding them less responsible for their actions than otherwise rational adults: in childhood and adolescence, dementia in old age, as a result of brain damage, brain tumours, other neurological and psychological disorders, or while sleepwalking. Increasingly, we recognise that our genes influence our capacity for free will and can predispose us to violence or addiction. Environmental factors such as upbringing shape our experiences and interact with genes, influencing our behaviour and choices. In these circumstances, we judge that physical or biological factors are interfering with the mind’s capacity to exercise free will and act rationally. But if there is no ‘mind’ separate from physical matter, no thoughts or actions that aren’t determined by external circumstances, in other words if we all lack free will, then should these exemptions from personal responsibility be extended to all of us?
It might be that these experiments probing conscious intention and voluntary action can begin to redefine free will in a more practical sense, determining the brain regions and pathways involved in rational decision-making, and establishing the boundaries of normal brain activity and anatomy. Instead of undermining free will, this field of research could help to uncover the conditions in which a narrower definition of free will – reflecting a person capable of making rational choices – is truly impaired.
This solution will never be completely satisfying, though, because it does not capture our intuitive understanding of free will. But if we accept a scientific account of human psychology and brain activity, what it reveals will never converge with our subjective experiences of free will. A more profound impact of this type of research is that it may eventually influence our instincts about how the mind works and reshape our attitudes to personal and moral responsibility.