This paper focuses on the tremor signal as a window to observe and analyze the central nervous system's functions and organization. In this idea it is proposed a custom system and some methodologies that reveal the cross-modalities influences, specifically, the increased complexity of the neuro-motor system generating the tremor as a result of photic driving activation method. The correlation dimension is used as a measure of system's complexity change and the behaviour of the physiological system is modelled using the Hindmarsh-Rose neuronal model. The proposed system includes: three neurons and their unidirectional coupling – considered to be a possible way the system changes its complexity –, the dynamical noise and the photic driving action. The correlation dimension (CD) analysis was performed on the real tremor signal and on the output signal of the modelled system. The global behaviour of the CD parameter proved to be similar in both cases. Thus, the results are promoting the idea of a complex and structured system that is accounting for the photing driving induced tremor.