The central auditory conduction at term date and three months after birth. III. Middle latency responses (MLRs).
Middle latency responses (MLRs) were obtained in 25 healthy newborns with a follow-up recording at 3 months in all but three. A four-channel recording provided topographic information. Linkage of the ear references reduced the myogenic contamination of the recordings. P0 and Na proved to be the most consistent components in the sinusoidal MLR wave sequence. Topographic differences suggest a generation of P0 and Na contralateral to stimulation. A significant latency decrease was found for P0 and na between term and 3 months. The most important latency and amplitude changes may occur before term date and immediately thereafter. The MLRs are the link between the auditory brainstem responses (ABRs) and the auditory cortical responses (ACRs), and it may be possible to use them for recordings in newborn infants. They provide information about the generation of specific components as well as regarding the auditory afference in the stimulus propagation between the brainstem and the cortical auditory areas.
D001303:Auditory Cortex / Q000502:physiology; D001306:Auditory Pathways / Q000502:physiology; D001307:Auditory Perception / Q000502:physiology*; D001933:Brain Stem / Q000502:physiology; D002657:Child Development; D004292:Dominance, Cerebral / Q000502:physiology; D005072:Evoked Potentials, Auditory; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature; D011930:Reaction Time / Q000502:physiology*; D009435:Synaptic Transmission; D000159:Vestibulocochlear Nerve / Q000502:physiology*