Abstract
ERA is a method which offers a great flexibility in the auditory stimulation. When applied on infants, the patient must generally be asleep. Sleep influences the cortical responses and the background EEG-activity. This study was undertaken to find correlations between changes in the EEG-pattern of the sleeping infant and changes in the auditory evoked response. Eight infants, aged 1 day-7 months, were studied during sleep. The EEG-signal level in three frequency bands was evaluated in relation to changes in the evoked responses. No consistent correlation could be established between the variables studied. According to our opinion the more peripheral electrical responses which are less influenced by sleep or sedation are superior to the cortical responses when examining small children. However, on older children and adults, who can be tested awake, the cortical responses can yield important diagnostic information beyond what the peripheral responses can.