Habit loop

Every habit follows the same loop: a cue triggers a routine, and at the end comes a reward that tells your brain: remember this. The model was popularised by the journalist Charles Duhigg; the groundwork was laid by researchers including the neuroscientist Ann Graybiel (in the brain) and the psychologist Wendy Wood (in everyday life). Deep in the brain, in the basal ganglia, the loop is bundled into a fixed sequence that kicks in as soon as the cue appears – largely without any conscious decision.

An example: the cue is the afternoon slump at 3 pm in the office. The routine is the trip to the vending machine. The reward isn't just the sugar, but also the short break and the chat with colleagues. If you only ban the routine (“no more sweets”), the cue and the need remain – and the loop wins out the next time tiredness hits.

The way out has three steps. First: identify the cue. Typical cues are the time of day, a place, a feeling, other people or a preceding action. For a week, note down what happens just before you reach for a snack. Second: work out which reward you're really looking for – energy, distraction, company, comfort? Third: swap the routine and keep the reward. If you're after company, make yourself a tea and spend five minutes chatting with a colleague by the window.

What matters is that the new routine delivers the same reward. Otherwise your brain feels cheated and falls back on the old programme. That's why substitute behaviours usually work better than bans. For families: children wanting something sweet after school is often a loop of hunger, transition and attention, too – a plate of fruit and ten minutes of listening take care of all three.