Ever wonder how your hearing compares to the average person your age? Give this hearing test by the folks at AsapSCIENCE a listen – then learn why you can (or can't) hear the frequencies being played in the video.
THIS IS IMPORTANT: if you want an accurate assessment, you need to adjust the video quality to 1080p (resolution settings also affect audio output, evidently) and you have to listen with headphones. Also: apparently YouTube's compression borked the 19 kHz frequency, so don't count that one. On second thought, maybe you can use the 19kHz frequency to tell if someone is lying about what she can and can't hear (we all know that person who would cheat on a hearing test).
How'd you fare? Your results will vary depending on the status of sensory receptors in your inner ear called "hair cells," which are prone to damage and degeneration over time. This type of hearing loss is known as sensorineural hearing loss (SNHL) – and while it includes the noise-induced hearing loss cited in the AsapSCIENCE video, SNHL can actually be brought on by a number of different factors, including a wide range of infections, drugs, and autoimmune disorders. Generally speaking, however, the outer hair cells, which are tuned to sensing higher frequencies, generally tend to go first – hence the age-dependent hearing effect featured in this video.
For more on the limits of human perception, see here.