The Mental Simulation of Motor Incapacity in Depression

In depression, negative beliefs are coupled with profound physical weakness. Specifically, the belief that one is incapable of altering events in order to prevent expected negative outcomes or bring about positive outcomes leads to bodily symptoms characterized by low energy, slow motor movement, and delays in the initiation of movement. The purpose of this article is to present a theoretical model describing the causal mechanisms that link these cognitive and somatic elements of depression. We propose that (a) the inability to alter events is conceptualized metaphorically as motor incapacity; (b) as part of this conceptualization, the experience of motor incapacity is mentally simulated; and (c) this simulation leads to both subjective feelings of lethargy and peripheral physiological changes consistent with motor incapacity.