Multi-level Models

The brain is a prototype of a hierarchical system, as Fig. 1 shows. More precisely, it is hierarchical dynamical system. To specify a dynamical system, characteristic state variables and evolution equations governing the change of state should be defined. At the molecular level, the dynamic laws can be identified with chemical kinetics, at the channel level with biophysically detailed equations for the membrane potential, and at the synaptic and network levels with learning rules to describe the dynamics of synaptic modifiability (see Table 1).