The Effect of Sleep on the Auditory Brainstem Response (ABR) and the Middle Latency Response (MLR)

Abstract

The ABR and the MLR were measured without interruption in 4 subjects during a whole night of natural sleep and compared with the awake responses. The conventional EEG activity was monitored during the whole procedure, which permitted a precise rating of the sleep stage during each recording period. Only minor changes were found in the latencies for the ABR during sleep. The MLR responses showed quite dramatic changes in morphology and latencies. Our results appear to indicate that the 40/sec stimulus presentation mode of the MLR will not be very effective during sleep due to the pronounced latency shifts of the different peaks in the MLR. The 40/sec response is based on an inter-peak latency of 25 msec. If this presumption is not fulfilled the different waves in the 40/sec response will not be superimposed and consequently enhanced in the averaging procedure.

The choice of distracting task can affect the quality of auditory evoked potentials recorded for clinical assessment

“…Whereas ABRs can be recorded almost unaltered during sleep (Campbell & Bartoli, 1986), MLR peak latencies and amplitudes can change when recorded during sleep or anaesthesia (Osterhammel et al, 1985). LLRs such as the N1-P2 complex can also easily be altered when the subject becomes drowsy and slips into sleep.…”

Electrically Evoked Auditory Brain Stem Responses (EABR) and Middle Latency Responses (EMLR) Obtained from Patients with the Nucleus Multichannel Cochlear Implant

“…The ABR, elicited with broadband unfiltered clicks, and various tonal stimuli, has been used widely for audiometric and neurological assessment purposes (Jacobson, 1985). The middle latency response (MLR) also has been used in various audiometric applications; however, the MLR is more susceptible than the ABR to influences of developmental age, natural sleep stages, and pharmacological effects (Jacobson, 1985;Osterhammel, Shallop, & Terkildsen, 1983;Kraus, Smith, Reed, Stein, & Cartee, 1985).…”

Clinical Implications of Primary and Nonprimary Pathway Contributions to the Middle Latency Response Generating System

“…According to this hypothesis, the adult MLR is dominated by a robust, later developing primary component, which is resistant to changes in sleep state (Kraus et al, 1988(Kraus et al, , 1989. In adults, Pa amplitude is largest during REM sleep and smallest during delta sleep (stages 3 and 4) (Collett et al, 1988;Okitzu, 1984;Osterhammel, Shallop, & Terkildsen, 1985). There is, however, general agreement that sleep does not impede the detectability of MLR waves in adults, as it does in children.…”