ANALYSIS OF COMPLEX PSYCHOLOGICAL SYSTEMS .2. DYNAMICAL MODELS AND COMPLEXITY IN A COUPLES THERAPY

We analyzed the course of a systemic couples therapy to demonstrate me thods of modelling the dynamics of psychotherapy. Psychological variab les and frequencies of speech were coded from video recordings in 3-mi nute intervals. We computed the forecastability and complexity of the time series using bootstrap tests with surrogate data sets. We also es timated the time-lagged links between the 8 rating variables by multiv ariate state space models. Modelling was applied over the entire cours e of 7 therapy sessions and over the phases prior to and after the int ervention which was assumed to be effective in this therapy system. Th is yielded the following results: the serial order of ratings is non-r andom whereas the sequence of speech frequencies is random in most cas es. As the problem constellation we find the symmetric escalation of t ension in the couple (one spouse's tension tends to increase the other 's tension). Furthermore, the complexity of time evolutions is general ly lower in the post phase after the intervention, i.e. the order of t herapy dynamics increases. From the pre and post intervention models w e conclude that the intervention embeds the problem gestalt ''symmetri c escalation'' in a series of additional interactions. The solution th us seems to carry the kernel of the problem with it. Finally, we discu ss the generalizability of this result and of the finding of an increa sed order (self-organization) of the therapy system.