ASSR Hearing Test
ASSR Test Clinic in India
ASSR “OR” Auditory Steady State Response
Auditory Steady State Response or say ASSR provides an accurate, frequency-specific estimate of the behavioural pure-tone audiogram.
It’s an objective test used for evaluation of hearing ability in children too young for traditional Audiometric Testing. The key point is that the person being tested must be very quiet and still in order to obtain reliable ASSR results.
An auditory steady-state response (ASSR) is an electrophysiological response that is evoked by an auditory stimulus which is presented through either insert ear phones, headphones or through BC transducer if doing BC ASSR. An ASSR typically uses frequency specific stimuli which is usually 500, 1000, 2000 and 4000 Hz with the aim of creating an estimated audiogram. In other words, ASSR is used to perform threshold estimation objectively.
Unlike auditory brainstem response which measures amplitude and latency of the response in the time domain, ASSR measures amplitudes and phases in the frequency domain. Another major difference is that in ABR it is only possible to test one frequency in one ear at a time in frequency-specific threshold ABR. ASSR allows for binaural testing; four frequencies in each ear at the same time. Which saves time and gives us more accurate information. Below figure shows a Normal ASSR graph.
ASSR shows frequency-specific thresholds and is a very useful tool in programming hearings aids for small children as behavioural audiometry is not possible in those population. A clinician can have a better understanding of gain which needs to be given in specific frequency and also to decide which type of hearing aid or amplification device would be more beneficial for the child.
ASSR also plays a major role in deciding candidate for Cochlear Implantation as with the help of it we can easily determine if the residual hearing is within or under the speech banana on Audiogram and if hearing aid provides limited benefits after trial.
The Below ASSR graph shows a hearing loss in few specific frequencies.
The auditory steady-state response (ASSR) can be thought of as an electrophysiologic response to rapid auditory stimuli. The goal of ASSR is to create an estimated audiogram. ASSR can be used binaurally while evaluating broad bands or four frequencies (500 Hz, 1000 Hz and 400 Hz,) simultaneously. ASSR Offers more spectral information more quickly and can estimate and differentiate hearing within the sever-to-profound hearing loss ranges. ASSR can be recorded using frequency-specific stimuli. Test frequencies of 500, 1000, 2000 and 4000 Hz are commonly used as ASSR carrier stimuli. These frequencies are modulated with respect to amplitude-frequency