Welcome to part four of On the brain, a Conversation series by people whose job it is to know as much as there is to know about the body’s most complex organ. Here, Neil Levy, Head of Neuroethics at Florey Neuroscience Institutes, considers the role of “choice” and “responsibility” in addictive behaviour. Enjoy.
Public discussions of addiction too often fall into the trap of simplistic slogans.
One side asserts addicts are fully responsible for what they do and can choose to act differently; the other side asserts addiction is a brain disease and that therefore addicts do not choose their behaviour.
Both views are partially true, but each is also very misleading. Addicts do make choices, including the choice to consume the drug to which they are addicted. But the neuropsychological changes involved in addiction mean their capacity for choice is abnormal enough to mean it would often be unreasonable to expect them to make alternative choices.
What is it to make a choice? Roughly speaking, we choose when we respond to reasons. A reflex is not a choice: when the doctor hits my kneecap, I don’t respond to a reason to jerk my leg.
A behaviour that looks more like a choice – compulsive hand-washing, say – might not be a choice if it is not responsive to reasons.
We test to see whether the behaviour is responsive to reasons by seeing how the person responds to various incentives. If the person is choosing, they will make a different choice given the right incentive.
So the compulsive hand-washer is choosing to wash her hands if she would stop for $100, or because she is hungry (enough), or what have you.