Related Experiment Video
Updated: Aug 5, 2026

Postsynaptic Recordings at Afferent Dendrites Contacting Cochlear Inner Hair Cells: Monitoring Multivesicular Release at a Ribbon Synapse
Published on: February 10, 2011
Normal summating potential to tone bursts recorded from the tympanic membrane in humans
J A Ferraro1, W L Blackwell, S J Mediavilla
1Hearing and Speech Department, School of Allied Health, University of Kansas Medical Center, Kansas City 66160-7605.
Abstract:
The use of tone-burst stimuli for electrocochleography (ECochG) may offer certain advantages over conventional broad-band clicks. Namely, the summating potential (SP) component can be examined at different frequencies and may be easier to define and measure. To apply these findings clinically, it would first be necessary to establish SP amplitudes as a function of tone-burst frequency in normal listeners. The purpose of the present study was to do this using the tympanic membrane (TM) as the primary ECochG recording site. ECochG was recorded from 20 normal ears. Stimuli included 500-, 1000-, 2000-, 4000-, and 8000-Hz tone bursts presented randomly at 90 dB nHL. Mean SP amplitudes at these frequencies were +0.19, +0.17, +0.08, +0.10, and +0.22 microvolts, respectively. Although mean amplitudes were slightly positive regarding baseline, individual amplitudes varied between -0.41 and +0.73 microvolts. This study offers additional evidence that the SP to tone bursts can be recorded from the TM. The normative data provided should be useful for extended studies involving clinical populations.
Related Concept Videos
Action Potentials
Action Potential
Membrane potential in neurons
Neurons typically have a resting membrane potential of about -70 millivolts (mV). When they receive...
Graded Potential
Graded potentials fall into two categories: depolarizing and hyperpolarizing. Depolarizing graded potentials typically occur when sodium (Na+) or calcium...
Action Potential
Membrane potential in neurons
Neurons typically have a resting membrane potential of about -70 millivolts (mV). When they receive...
Action Potential: Phases of Stimulation
Resting Phase:
In this phase, the cell's membrane is at its resting potential, typically around -70 millivolts (mV) for neurons. Inside the cell, there is a higher concentration of potassium ions (K+) and a lower concentration of sodium ions (Na+). Voltage-gated sodium channels are closed, and...
Integration of Synaptic Events

