Recruitment means steep loudness growth that catches up to normal at high levels

Evidence

This function is much steeper than the broken 45°-line; it has an elevated threshold but reaches the broken line at high levels. All these effects are typical of what is called recruitment. — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 1963

Categorization

• DEFINE: Defines recruitment precisely: elevated threshold with abnormally steep growth that rejoins normal loudness at high levels.
• XREF: A clinical sign of cochlear damage long described in audiology texts; this gives the psychoacoustic mechanism behind it.
• QUESTION: How does the DLM’s recruitment model handle the 20 dB-above-threshold catch-up claim in the next paragraph — does it match real patient data?