Professional forecasters’ long-run inflation expectations overreact to news and exhibit persistent, predictable forecast errors. We uncover the cognitive biases allowing an imperfect information model to explain these features of the data. Our analysis highlights substantial, time-varying heterogeneity in forecasters’ responses to public information, with sensitivity declining across all forecasters when monetary policy is constrained by the effective lower bound. The model serves as a framework for evaluating, in real time, whether the inflation paths communicated by policymakers are consistent with long-run expectations remaining anchored at the central bank’s target.