Question
Can you please explain tone burst (TB) ramping?
Answer
Imagine a singe stimulus with an onset, an offset, and maybe a plateau or period between the onset and offset. The ramping is the shape of the stimulus from the onset to the beginning of the plateau, or how intensity is increased from no stimulation to the maximum amplitude for a single stimulus.
Linear ramping is a straight line amplitude increase. Research many years ago showed that linear ramping of stimulus onset produced unwanted energy at frequencies above and below the test frequency. Experimentation showed that it was possible to alter the frequency specificity of stimulation by modifying the shape of the ramp. This is now done with different mathematical formulae that vary the shape. Some time ago an electrical engineer named Blackman developed an equation for a stimulus onset ramp or envelope that minimized "spectral splatter" of abrupt sound stimulation. The ramp begins to increase slowly and the more rapidly increases as the maximum is approached.
My New Handbook of Auditory Evoked Responses (Hall, 2007) book includes a more detailed explanation of this concept.
For an in-depth discussion of this topic, please view Dr. Hall’s recorded course on AudiologyOnline, Application of ABR in Objective Assessment of Infant Hearing
Reference
Hall, J.W. (2007). New handbook of auditory evoked responses. TX: Pearson.
