Mental simulation
Running an imagined scenario forward in the mind to see how it plays out.
What it means
Mental simulation is the cognitive construction and 'running' of hypothetical or future episodes — imagining a sequence of events, actions, and outcomes — to predict, plan, problem-solve, and regulate emotion. It draws on the same constructive memory machinery used to recall the past, which is why imagining the future and remembering are neurally and behaviorally intertwined. Simulations come in outcome form (picturing the desired end state) and process form (picturing the steps to get there); process simulation tends to improve planning and performance, while pure outcome simulation can breed complacency. Its accuracy is bounded by what the simulator represents, so neglected details and current states bias the result. It is foundational to prospection, counterfactual thought, and affective forecasting.
Examples
A student who mentally rehearses the specific steps of studying — when, where, which chapter — follows through more than one who only fantasizes about acing the exam.
A team that walks through launch day hour by hour — who posts, who watches the dashboard, what happens if it breaks — ships more smoothly than one picturing the celebration.
Planning a house move, you simulate the drive and the boxes but not the two hours hunting for parking: the run-through only contains what you thought to put in it.
First described in Kahneman & Tversky (simulation heuristic, 1982); Taylor et al. (1998).