Objective. Electroconvulsive therapy (ECT) is an effective treatment for patients suffering from a major depressive episode, especially older ones. Identification of specific responses within early ECT sessions remains an issue of debate, however. Hence, this pilot study prospectively examined the outcome in terms of depressive signs, symptom by symptom, throughout a course of ECT, concentrating particularly on psychomotor retardation symptoms. Methods. Nine patients were clinically evaluated several times during the ECT course, before the first session and then weekly (over 3 to 6 weeks, according to their evolution), by completing the Montgomery–Asberg Depression Rating Scale (MADRS), the Mini-Mental State Examination test, and the French Retardation Rating Scale for Depression (ERD) for assessing the severity of psychomotor retardation. Results. Non-parametric Friedman tests showed significant positive changes in mood disorders during ECT in older depressive patients (mean: -27.3% of initial MADRS total score). Fast improvement in ERD score was observed at t1 (i.e., after 3–4 ECT sessions), whereas a slightly delayed improvement in the MADRS scores was found at t2 (i.e., after 5–6 ECT sessions). Moreover, the scores for items linked to the motor component of psychomotor retardation (e.g., Gait, Postural control, Fatigability) were the first to significantly decrease during the first two weeks of the ECT course compared with the cognitive component. Conclusions. Interestingly, participants' concentration on daily functional activities, their interest and fatigability, and their reported state of sadness were the first to progress, representing possible precursor signs of positive patient outcomes following ECT.