Abstract: A real-time simultaneous measurement apparatus includes: a hemoglobin information-receiving portion that sequentially receives hemoglobin information, which is information relating to the amount of hemoglobin in a head portion of a test subject, from a NIRS brain-measuring apparatus that receives a synchronization signal output by a synchronization signal output apparatus and acquires the hemoglobin information when the synchronization signal has been received; a brain wave information-receiving portion that sequentially receives the brain wave information of the test subject, from an EEG brain wave-measuring apparatus that receives a synchronization signal output by the synchronization signal output apparatus and acquires the brain wave information when the synchronization signal has been received; a synchronization processing portion that performs processing that synchronizes the hemoglobin information and the brain wave information; and an output portion that outputs the synchronized hemoglobin information