Human generated random numbers and a model of the human brain functions

We consider the human random generation test (HRG) as a probe to a function of the human brain and explore the possibility of applying it to health-care products. HRG is a psychological test designed to check the flexibility of thinking in a simple manner. In the early days when HRG was studied in the field of clinical psychology, ability to produce a reasonable amount of randomness was connected to the patients mental state since it was known that a patient at the advanced stage of a certain mental disease loses this ability considerably. After much effort of extracting useful information from such data, they ended up with only a partial success in identifying some typical patterns produced by patients of advanced stage of mental disease. We reconsider this problem with much advanced resources in computer facilities and techniques compared to those days. Our first attempt was to prepare data as computer files and fit them by a statistical model with large number of parameters. More recently we took data directly into computer files and analyzed them by means of HMM-type models. Based on these results we propose to use HRG as a supplemental tool for noninvasive diagnosis, together with biomedical information such as heart pulses or the chemical content of blood which have been made possible in a noninvasive way.