How can I find the source of this kind of apartment noise?

Since yesterday, someone has been screaming for about 1 to 2 seconds continuously, except when they are sleeping. It sounds like the noise is coming from someone's balcony and is amplified by the resonance within the complex, but the person screams so briefly and irregularly—sometimes screaming again just 5 minutes later—that it's hard to tell. It's as if they are playing a game: whenever I prick up my ears to try and locate the source, they go silent, making it impossible to pinpoint where they are. Is there any way to find out where this crazy person lives?