At what frequency does an increase in latency and decrease in amplitude occur for BAER?

For Brainstem Auditory Evoked Responses (BAER), changes in latency and amplitude can occur at specific frequency bands, particularly as stimulus rates increase. An increase in stimulus frequency typically results in a lengthening of the latency of the BAER waves due to neural processing delay, while the amplitude can decrease due to neural fatigue or signal interference at higher rates.

At 30 Hz, the evoked potential responses are often analyzed, as this frequency allows for a clear representation of the auditory pathways and is commonly used in clinical settings. The physiological basis for the change in latency and amplitude is rooted in the properties of the auditory system's response to repetitive stimuli; as the rate increases, the system can become less efficient, leading to the observed changes.

The other frequencies listed do not produce the same consistent changes in latency and amplitude characteristic of BAER testing at 30 Hz. Lower frequencies like 10 Hz may not stress the neural pathways, leading to less noticeable changes, while higher frequencies such as 60 Hz might push the system to a point of fatigue beyond what is typically analyzed in BAER assessments. Therefore, 30 Hz is the frequency at which these specific measurements are reliably taken and interpreted in the context of BAER evaluations.