FIG. 5.

(Color online) Schematic diagram showing the effects of mechanical, metabolic, and neural pathologies on DPOAEs and HTs. The regression line shows an inverse relationship between DPOAEs and HTs. The green dot on the regression line depicts a relationship between DPOAE and HT in “normal” individuals (control group). The black dot shows reduced DPOAE and elevated HT as predicted by the linear model (i.e., “proportional” decline in DPOAE). The blue dot presents more decline in DPOAE than predicted by the linear model, indicating predominant mechanical damage to the cochlea. The yellow dot shows less decline in DPOAE than predicted by the linear model, which suggests disproportional metabolic damage to the cochlea. The red dot presents elevated HT and no decline in DPOAE, suggesting a disproportional neural origin of the cochlear damage. The blue, yellow, and red lines show the error in prediction (ΔDPOAE).