Check Your Brain Speed:
Here's a flash-based test check your brain's auditory processing speed. I tried it once, averaging 46ms, which according to the chart above isn't too shabby for someone of my advanced years.
"Auditory processing speed is important because much of the information we receive each day is communicated through sound, especially speech. The faster we can take in information accurately, the better we can keep up with, respond to and remember what we hear.
This 10-minute test asks you to listen and respond to elemental parts of speech called frequency sweeps to gauge your auditory processing speed. The test measures how accurately you can process sounds at varying speeds."