Seven challenges in affective inertia research.

Affective inertia-the persistence of emotional states over time-has garnered growing attention in affective science due to its implications for psychological well-being and emotion regulation. Yet empirical progress has been hindered by conceptual ambiguities, measurement challenges, and statistical limitations. Here, we identify seven interrelated challenges spanning three domains: conceptual (e.g., conflating inertia with emotional stability), measurement (e.g., misalignment between ordinal data and parametric models), and statistical modeling (e.g., violations of stationarity assumptions). Addressing these challenges requires dynamic approaches that capture the temporal complexity of emotional processes and differentiate adaptive from maladaptive persistence. We review theoretical developments and empirical innovations-including advances in modeling, assessment design, and assumption testing-that offer a path forward. By clarifying the measurement and interpretation of affective inertia, this work aims to enhance both basic emotion research and its clinical translation. (PsycInfo Database Record (c) 2026 APA, all rights reserved).