The effects of lead on otoacoustic emissions and auditory evoked potentials in monkeys

• Published in: Neurotoxicology and teratology Vol. 17; no. 6; pp. 633 - 644
• Main Authors: Lasky, Robert E., Maier, Mary M., Snodgrass, Ellen B., Hecox, Kurt E., Laughlin, Nellie K.
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01-11-1995; Elsevier Science
• Subjects: Animals; Animals, Suckling; Auditory evoked brain stem responses; Biological and medical sciences; Chemical and industrial products toxicology. Toxic occupational diseases; Distortion product otoacoustic emissions; Evoked Potentials, Auditory - drug effects; Evoked Potentials, Auditory, Brain Stem - drug effects; Female; Hearing - drug effects; Lead - toxicity; Lead toxicity effects; Macaca mulatta; Male; Medical sciences; Metals and various inorganic compounds; Middle latency responses; Pregnancy; Prenatal Exposure Delayed Effects; Rhesus monkeys; Toxicology; Auditory evoked brain stem responses; Middle latency responses; Lead toxicity effects; Distortion product otoacoustic emissions; Rhesus monkeys; Otoacoustic emission; Toxicity; Monkey; Electrophysiology; Auditory disorder; Distortion; Latency; Heavy metal; Vertebrata; Mammalia; Animal; Auditory evoked potential; Primates; Lead; ENT disease
• ISSN: 0892-0362; 1872-9738
• DOI: 10.1016/0892-0362(95)02006-3

Auditory functioning was assessed in two groups of adult rhesus monkeys (11 years of age). One (
n = 11) received modest exposure to lead early in life and the other (
n = 8) served as controls and did not receive any lead supplementation. Two lead-exposed monkeys had abnormal distortion product otoacoustic emissions (DPEs) and smaller amplitude or absent evoked potentials. These monkeys had the highest blood levels recorded in their respective groups. For the remaining lead-exposed monkeys there was little difference between their DPEs and the DPEs of the control monkeys with one exception. DPE amplitudes of the control monkeys increased more rapidly as a function of stimulus level than those of the lead-exposed monkeys at most frequencies. There was also a significant but modest effect of lead exposure on the auditory brain stem evoked responses (ABRs) of these lead-exposed monkeys. There was no apparent effect on the middle latency evoked responses (MLRs), although that result could be due to the relatively greater variability of the MLR.