Neuroscience says there’s no such thing as free will. A psychologist explains why that might not be true
It's a hotly debated topic, but the way our brains work can give us some insight.
The question of free will is still hotly debated. On the one hand, we clearly experience ourselves as able to make choices and freely act on them. If you fancy some crisps, you can choose to walk into a shop, buy a packet and eat them. Or you can choose to eat a pastry, a salad, or nothing at all. This certainly feels like free will.
On the other hand, neuroscience evidence clearly shows that the brain usually initiates our actions before we’re aware of them. Here’s what I mean. Your brain’s primary task is to regulate the systems of your body to keep you alive and well. But there’s a snag: your brain spends its days locked in a dark, silent box (your skull) with no direct access to what’s going on inside your body or outside in the world.
It receives ongoing information about the state of your body and the world – ‘sense data’– from the sensory surfaces of your body (your retina in your eyes, your cochlea in your ears, and so on). These sense data are outcomes of events in the world and inside your body. But your brain does not have access to the events or their causes. It only receives the outcomes. A loud bang, for example, might be thunder, a gunshot, or a drum, and each possible cause means different actions for your brain to launch.
How does your brain figure out the causes of sense data, so that it prepares the best actions? Without direct access to those causes, your brain has to guess. And so, in every moment, your brain remembers past experiences that are similar to your present circumstances, to guess what might happen in the next moment, so it can prepare your body’s next action.
Guessing (and potentially correcting mistakes) is more efficient than reacting from scratch. These predictions are, in effect, your brain changing the firing of its own neurons to prepare your body to act, a second or so before the movements actually occur. This predictive process happens completely outside your awareness, but it is continuous throughout your life, and a growing number of scientists are now pretty sure that it’s a primary driver of your actions.
From this perspective, your brain’s decision to eat a packet of crisps was launched as a plan for action before your brain made itself (you) aware of this plan. So this action, like most of your actions, was guided by predictions that were under the automatic control of your memory and your current surroundings. This description of your brain’s inner workings certainly seems to suggest an absence of free will.
And so we arrive at the point where the free will debate has lingered for a long time. We won’t settle the debate here, but I’ll highlight one puzzle piece that is often ignored. Your brain predicts (in large part) by reassembling your past experiences that are similar to the present moment. That means every new experience you cultivate for yourself – every new thing you read, every new person you talk to, every new thing you learn – is an opportunity to change what your brain will predict in the future, and which actions you may take.
In other words, your brain (meaning you) can nudge its future predictions in various directions, right now, by investing in new experiences. You are continually cultivating your past as a means of controlling your future. This may be a form of free will, but it’s extended over time and therefore different from how we usually think about free will in the moment. If you practise a skill, whether it’s riding a bicycle, or talking to someone who believes things that you abhor, you hone your brain’s predictions until that skill becomes automatic and likely to be repeated.
With practice and a little investment of energy, you can make some automatic behaviours more likely than others and have more control over your future actions. Perhaps not as much control as you might want, but more than you might think.
- This article first appeared in issue 370 of BBC Science Focus Magazine – find out how to subscribe here
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Lisa is a professor of psychology at Northeastern University and the author of Seven And A Half Lessons About The Brain (£14.99, Picador). She is one of the most cited scientists in the world for her research into psychology and neuroscience. Lisa is Chief Science Officer for the Center for Law, Brain & Behavior at Massachusetts General Hospital, and received a National Institutes of Health Director’s Pioneer Award for her revolutionary research on emotion in the brain.