Abstract: An apparatus and method are provided for analyzing information relating to the physiological and psychological conditions of a driver. Psychological conditions such as comfortableness or degree of alertness are estimated on the basis of physical data such as fluctuation in brain waves. This apparatus comprises a first neural network having a pre-processed 1/f fluctuation signal for brain waves as an input and for estimating a degree of alertness of the driver, and a second neural network receiving the estimated degree of alertness and the pre-processed 1/f fluctuation signal, for estimating and outputting driving comfortableness. By employing a neural network, which has a mapping ability as well as flexible adaptability even for non-linear data, based on the learning function, more accurate estimation of mental conditions can be achieved in comparison with conventional statistical analysis.