DOI: 10.5061/dryad.w3r22813p
title: Data and code from: Viscoelasticity explains fast adaptation in the auditory amplifiers of mammals

description: When we hear, sound-induced deflections of our sensory outer-hair-cell
 bundles are transduced into receptor currents. These receptor currents
 drive the cochlear amplifier, which is required for our ear's high
 sensitivity, broad dynamic range, and sharp frequency selectivity.
 Adaptation maintains the sensitivity of receptor currents to bundle
 deflections, but the mechanisms underlying adaptation in outer-hair-cell
 bundles remain under debate, and how adaptation works at physiologically
 relevant frequencies is unclear. We propose a mechanism for the fastest
 components of adaptation, based on viscoelastic adaptation elements. To
 evaluate this proposal, we fit a mathematical model of an outer-hair-cell
 bundle with viscoelastic adaptation elements to twelve independent
 experimental observations. We validate the model by successfully
 predicting an observation not used for fitting --- how much
 receptor-current sensitivity is maintained by fast adaptation. The
 experimentally constrained model predicts the effects of fast adaptation
 for physiologically relevant frequencies. We show that there is
 considerable deflection-current hysteresis, the receptor current can lead
 the bundle deflection to a large extent (up to 61° phase lead), and that
 fast adaptation greatly high-pass filters the receptor current. Owing to
 viscoelastic fast adaptation, the dynamic range of the outer-hair-cell
 bundle depends on the stimulus frequency. These predictions and others are
 experimentally testable. Because viscoelastic fast adaptation
 substantially affects receptor-current sensitivity, hysteresis, phase
 leads, high-pass filtering, and dynamic range, we expect viscoelastic fast
 adaptation to greatly impact the cochlear amplifier and hearing. Here, we
 provide the experimental data used to constrain the mathematical models
 and the modeling code.
description: # Data and code from: Viscoelasticity explains fast adaptation in the
 auditory amplifiers of mammals Dataset DOI:
 [10.5061/dryad.w3r22813p](10.5061/dryad.w3r22813p) ## Description of the
 data and file structure ### Description of the data and file structure The
 data is in CSV format and can be read by any text editor. These data are
 measured values for different hair bundles. #### Files and variables
 A_14pts_Peng13Fig4H.csv contains adaptation extent values.
 Ppeak_Peng13Fig1a.csv contains peak current values. Ppeak_Peng13Fig2a.csv
 contains peak current values. Ppeak_Peng13Fig4a.csv contains peak current
 values. Prest_Peng13FigS3C.csv contains resting current values.
 R_14pts_Peng13Fig4G.csv contains long timescale fraction values.
 Shift_Peng13Fig6C.csv contains adaptation shift values.
 tau1_14pts_Peng13Fig4E.csv contains short timescale values.
 tau2_14pts_Peng13Fig4F.csv contains long timescale values. ###
 Code/software Mathematica 14 or later, or the free Wolfram Player will
 open the nb files. The data files are read in by the nb code files.
 Part1_calibration_phasors.nb fits the data and calculates model results.
 Part2_hysteresis.nb calculates model hysteresis. Part3_freq_analysis.nb
 calculates model frequency responses. Part4_shift.nb calculates the modle
 adaptation shift. Part5_change_params_compare_fits.nb calculates
 adaptation time series owing to parameter variation.
 Part6_change_params_compare_shifts.nb caculates shifts owing to parameter
 variation. Part7_stiffnesss_increase.nb calculates the bundle stiffness
 and resting deflection when the adaptation stiffnesses are doubled.
 Part8_hysteresis_stiffness_increase.nb calculates model hysteresis when
 the adaptation stiffnesses are doubled.
 Part9_freq_analysis_stiffness_increase.nb calculates model frequency
 responses when the adaptation stiffnesses are doubled. ## Access
 information Data was derived from the following sources: * Peng et al.
 (2013) *Neuron* 80.