An Experimental Study on Diphasic Acoustic Reflex Patterns in Normal Ears

The existence of two kinds of diphasic acoustic reflex patterns for human ears is proved experimentally. The "false" irregular patterns, which originate from the transformation of monophasic resistance and reactance responses, obey the properties described in an earlier, theoretical paper; they are certainly not connected with any pathology. The "true" diphasic responses, for which all the acoustic admittance and impedance components seem to be diphasic, can be separated from the false ones when the shape of the reflex is studied as a function of the SPL of the sound stimulus or the pressure in the ear canal.