The quantum-like approach of psychosomatic phenomena suggests an explanation of the correlations between mind and body in terms of quantum-like entanglement, that is, without appealing to any concept of psychophysical, efficient causality. This approach is developed within the Hilbert space formalism and its general consequences are drawn. It is first illustrated by a simple, qualitative model of the placebo effect which shows that representing psychosomatic states by entangled states can explain that purely psychological factors can produce a-causal changes of physiological (...) parameters. Then, a dynamical, quantitative and predictive model of bipolar disorder which makes use of the unitarity of the temporal evolution of psychosomatic states due to biological and psychological rhythms is worked out. This model can explain some current observations, like for example the severe fluctuations in mood between depression and mania, and it can forecast the moment of shifting. In addition, it justifies the efficiency of chronotherapy on theoretical basis. (shrink)