This Application Note details setup and measurements for Auditory Brainstem Response (ABR) measurements using an MP160/MP150 data acquisition system and AcqKnowledge 4.1 or above software.
Whenever a sound wave is detected by the ear, it triggers a number of neuro-physiological responses along the auditory pathway. An action potential is conducted along the eighth nerve, the brainstem, and finally to the brain.
About one third of a second after initial stimulation, the signal evokes a response in the area of the brain where sounds are interpreted. These response signals are so small that they are frequently masked by the “background noise” of electrical activity in the brain. This interference is random with respect to the initial stimulation.
If you find an average of this interference signal, it will approach zero. However, since the evoked response is dependent on the stimulus, it should occur at the same time relative to the stimulus when the process is repeated. Therefore, if you repeat this stimulus-response process many times the “background noise” will disappear and what will be left is the neuro-physiological response of principal interest.
The ABR Calibration Guide outlines precise test equipment calibration to ensure proper signal-to-noise levels (S/N) and signal time delays for Auditory Brainstem Response (ABR) measurements.
For ABR studies, calibrate the OUT101 Tubephone with anEtymotic ER-7C Probe Microphone—this microphone provides a calibrated output voltage which is a function of applied Sound Pressure Level (SPL). The sensitivity is 50 mV/Pascal (-46 dB re: 1 V/uBar): 0 dB SPL = 0 dBuV. Place the Probe Microphone insert tube in the auditory canal prior to the insertion of the OUT101 foam tip. The OUT101 Tubephone sound delivery tube and the Probe Microphone sound input tube will then be exposed to the same auditory chamber. Accordingly, the SPL is recorded, via the Probe Microphone, simultaneously with applied auditory stimulus from the OUT101 Tubephone.
EEG: Electroencephalography - Wired and wireless EEG solutions. Record up to 32 channels of EEG and use software features for filtering, removing EOG artifacts, and complete frequency analysis.
ERS: Evoked Response - Record evoked, late, and field potentials, as well as startle and nerve conduction. Powerful on- and off-line averaging features (P300), and dual stimulation ability with the MP150.
Psychophysiology - Record and analyze BP, ECG, HRV, EDA, EMG, EEG, EOG, RSP, etc. Interface to stimulus presentation programs...use automated analysis routines to easily score and analyze data.
Amplifiers & Interfaces - Use BIOPAC amplifiers with MP Systems, as stand-alone devices, or with 3rd-party flow meters, force plates, sono-micrometers, telemetry equipment, metabolic carts, etc.
Basic principles of physiological data collection covers fundamentals of data collection and equipment configuration equipment to help you refine experiment protocols and avoid costly missteps. Frazer Findlay, CEO of BIOPAC, discusses common mistakes with physiology recording and shares his secrets for collecting great data. Topics include: How to prep a subject and where to place electrodes; Which type of electrodes work for different body signals; Analog to Digital Conversion; Sample rates (correct vs. incorrect); Filtering; and Scaling and calibration.Watch On Demand Now!
Recent Exercise Physiology studies feature BIOPAC’s MP Research series of Data Collection recorders and AcqKnowledge software. These studies promote healthy living and observe muscle response to normal physiological motions during exercise! Trampoline Workouts for Seniors? As we get older, our joints ache and muscles stiffen—but scientists are finding new ways to not only help us […]
BIOPAC’s just released Introductory ECG Guide addresses fundamental to advanced concerns to optimize electrocardiography data recording and analysis. Topics include: ECG Complex; Electrical and Mechanical Sequence of a Heartbeat; Systole and Diastole; Configurations for Lead I, Lead II, Lead III, 6-lead ECG, 12-lead ECG, precordial leads; Ventricular Late Potentials (VLPs); ECG Measurement Tools; Automated Analysis Routines […]