An information acquiring method configured to acquire brain activity information from biological subjects (502) presented a sensory stimulus, in which the brain activity information is acquired by measuring the brain activity in at least one region of the brain areas of the biological subjects including the visual cortices of the cerebral cortex, the auditory cortices of the cerebral cortex, and the vestibular cortices of the cerebral cortex； while the stimulus which changes over time is presented to the brain areas by stimulus presentation means (503, 505) before and after the sensory stimulus is presented to the brain areas.
