Brainstem auditory evoked potentials BAEP

Brainstem auditory evoked potential (BAEP) latency (Holdstein et al. 1986 Otto et al. 1985 Robinson et... 

These children were also evaluated through electrophysiological means. Otto et al. (1981) reported a significant linear association between PbB and slow-wave voltage. In a follow-up of this group after 5 years (Otto et al., 1985), the relationship of slow-wave responses to PbB along with a significant association of pattern-reversal evoked potentials (PREPs) and brainstem auditory evoked potentials (BAEPs) with PbB persisted. 

Electroencephalogram measures have been shown to be sensitive to some forms of neurological insult, and they have been used in the diagnosis of a variety of neurological disorders. Other neurophysiological measures, such as brainstem auditory evoked potential (BAEP), and pattern-reversal visual evoked potential (PREP), are supposed to be stable, relatively age-independent, and free from social or cultural influences. 

In addition to the experimental conditioning tests, Otto et al (1985) used two clinically validated measures of sensory function, the pattern-reversal visual evoked potential (PREP) and the brainstem auditory evoked potential (BAEP). Exploratory analysis of PREPs revealed increased amplitude and decreased latency of certain components as a linear function of original PbB levels. Although these results were contrary to predictions, the findings are consistent with the results of Winneke et al (1984), who found an association between increased PbB levels and decreased latency in the primary positive component of PREPs in children. BAEP results of the five-year follow-up study also indicated significant associations between original PbB levels and increased latencies of two components (waves III and V), indicative of auditory nerve conduction slowing. 

Visual evoked potentials (VEPs) and brainstem auditoiy evoked potentials (BAEPs) measure speed of conduction in the nerves that ran from the eyes and ears, respectively, to the relevant locations in the brain. On stimulation, nerves send signals in the form of waves that can be detected, and the time it takes for an impulse to initiate an evoked potential is latency. The VEP is the first positive wave and usually occurs at 100 ms (PlOO latency) after the visual stimulus. That measure is very sensitive to demyelination of the optic nerve. BAEPs also have discrete waveforms. Wave I arises from the auditory nerve, and its latency reflects peripheral transmission time wave 111 is generated predominantly from the auditoiy pathway in the lower brainstem and wave V is generated from the upper brainstem. The use of interpeak latencies helps distinguish changes in peripheral auditory nerve latency from changes in brainstem transmission in the auditoiy pathway. 

Discalzi, G.L., F. CapeUaro, L. Bottalo, D. Fabbro, and A. Mocellini. 1992. Auditory brainstem evoked potentials (BAEPs) in lead-exposed workers. Neurotoxicology 13(l) 207-209. 

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