Résumé
According to dynamical psychology, self-esteem can be considered as a phenomenon that emerges from numerous interactions in brain activity and which can vary far from its equilibrium point (Nowak et al., 2000). Thus, researchers should not focus only on the level of self-esteem as is usually done in typical nomothetic approaches. Dynamical psychologyneeds idiographic approaches in order to determine intraindividual instability and to forecast the dynamics of time series. In the sport domain, Amorose (2001) showed that intraindividual variability is an important index of one’s self-perception profile. Over a 1-year period of bidaily observations of 8 sedentary adults, Ninot et al. (2004) showed that the dynamics of both global self-esteem and physical self exhibited noisy fluctuations around a slowly varying mean. Self-esteem appeared to be neither a trait, nor a state, nor a dynamical equilibrium(homeostasis). Rather, the self behaved following a dynamic adjustment underlain by the combination of two opposite processes: a preservation process, which tends to restore the previous value after a disturbance; and an adaptation process, which tends to inflect the seriesin the direction of the perturbation. From a methodological viewpoint, time series analyses and brief instruments are appropriate for exploring some basic hypotheses suggested from nomothetic approaches to self-esteem. Dynamical psychology can provide major advances inour understanding of the relationships between instability of self-esteem and depression, forecasting athletes’ depression, and flows of influence in the hierarchical structure of the physical self.