A method of determining affirmative and negative response areas in a cerebral cortex of a human subject under a test, comprises (A) providing a testing apparatus to detect real-time variations in cerebral blood flow, (B) generating a test array consisting of a plurality of test points in a tested area of the subjects head to detect real-time variations of the cerebral blood flow in the tested area, wherein the tested area approximately corresponds to an affirmative or negative response area in the cortex (C) asking a question to the human subject, wherein the question is designed so that an answer for the question is either yes or no and (D) determining a precise position of the affirmative or negative response area in the cortex, according to an active region corresponding to the real-time variations of the cerebral blood flow generated in a predetermined time within the tested area after answering.
