  Experimental results presented in this paper supports the hypothesis on
quantum-like statistical behaviour of cognitive systems (at least human
beings). Our quantum-like approach gives the possibility to represent mental
states by Hilbert space vectors (complex amplitudes). Such a representation
induces huge reduction of information about a mental state. We realize an
approach that has no direct relation with reductionist quantum models and we
are not interested in statistical behavior of micro systems forming the macro
system of the brain. We describe only probabilistic features of cognitive
measurements. Our quantum-like approach describes statistics of measurements of
cognitive systems with the aim to ascertain if cognitive systems behave as
quantum-like systems where here quantum-like cognitive behavior means that
cognitive systems result to be very sensitive to changes of the context with
regard to the complex of the mental conditions.
