Application to Psychotherapy: The Mixture of Deterministic and Stochastic Interventions

Abstract

The Fokker-Planck model of psychotherapy integrates stochastic with deterministic interventions. In a case example of a client with a severe depressive episode, we computer-simulate how the underlying attractor landscape (three point attractors located at different values of depression) can be changed by stochastic and deterministic simulated “interventions.” We illustrate how random inputs are capable of destabilizing a psychopathological attractor. Contextual interventions, originating from common factors associated with emotional and motivational processes, may change the attractor landscape as a whole. They act like affordances. We suggest how a momentary deterministic “push” of the system state can be modeled mathematically. We conclude with the suggestion that in naturalistic psychotherapy practice, one commonly sees a mixture or sequence of deterministic, stochastic, and contextual interventions. There is probably no one ideal course of therapeutic action, and different therapy approaches may be similarly effective, so that several roads may “lead to Rome.”