ABSTRACT
Auditory middle latency and steady-state responses (MLR/SSRs) were recorded in normal infants (aged 3 weeks to 28 months) and adults. SSR amplitudes were maximum using stimulus presentation rates near 40 Hz in adults. By contrast, the infant data showed no consistent amplitude maximum across the rates tested (9-59 Hz). With the exception of the brain-stem response wave V to MLR Na deflection, MLR components in infants' responses to 10.85 Hz clicks did not show any consistent pattern. To investigate the hypothesis that the 40 Hz SSR is derived from overlapping of the 10 Hz MLR components, 43.4 Hz SSRs were synthesized from the responses recorded at 10.85 Hz and compared with those recorded at 43.4 Hz. The predictive accuracy of the synthesized 43.4 Hz SSRs was significantly better in adults than in infants. The results of these studies indicate the presence of large age-related differences in the auditory MLR and SSR, and in the relationship between the two responses.
Subject(s)
Evoked Potentials, Auditory , Acoustic Stimulation/methods , Adult , Electroencephalography , Homeostasis , Humans , Infant , Infant, Newborn , Reaction TimeSubject(s)
Brain Chemistry , Liver/analysis , Thallium/analysis , Animals , Cattle , Graphite , Lasers , Male , Mice , Spectrometry, Fluorescence/instrumentationABSTRACT
The prolonged freedom from rabies enjoyed by Ireland is based on both its island location and the rigid enforcement of national legislation. The yachting tourist and the increased level of shipping activity in ports and harbours are a major threat of disease introduction. Mass media publicity and public awareness are the main safeguards necessary to protect the freedom of our island.
