Real and imaginary parts of the impedance of a preparation 4.5 mm from the round window at three radial locations: tunnel of Corti (•), inner hair cell (○), and first-row outer hair cell (▵). Notice that the magnitude of the impedance is greatest at the tunnel of Corti. The arrow indicates the characteristic frequency according to the map of Tsuji and Liberman (1997). The fit functions are given by Eq. 8. Parameters are (mean ± SD). tunnel of Corti, k = 0.292 ± 0.005; c1 = 237 ± 27; c2 = (1.75 ± 0.03) × 10−5; c3 = (2.38 ± 0.28) × 10−5; c4 = (7.11 ± 0.95) × 10−5; and c5 = (7.92 ± 0.61) × 10−6. Inner hair cell, k = 0.197 ± 0.003; c1 = 49.5 ± 19.3; c2 = (7.00 ± 0.23) × 10−6; c3 = (1.56 ± 0.21) × 10−5; c4 = (7.39 ± 1.10) × 10−5; and c5 = (3.13 ± 0.34) × 10−6. First-row outer hair cell, k = 0.082 ± 0.002; c1 = 23.7 ± 8.0; c2 = (3.21 ± 0.46) × 10−6; c3 = (6.03 ± 0.47) × 10−6; c4 = (1.53 ± 0.38) × 10−5; and c5 = (1.94 ± 0.25) × 10−6. Stiffness of cantilever, 1.20 N/m. All units are SI.