title: Right-left correlation in guinea pig ears after noise exposure.
abstract: In order to investigate whether experimental material consisting of noise-exposed animals should be regarded as 'ears' or 'animals', a comparison was made between the permanent threshold shifts in the right and left ears in 53 groups of noise-exposed guinea-pigs, with 5 animals in each group. The action potential (N1) thresholds were measured at fourteen frequencies in both ears. In the noise-exposed animals, the threshold elevations were up to 40 dB. The average right-left correlation coefficient within each group was about 0.79, regardless of noise energy. The degree of correlation was significantly greater after impact noise than after continuous noise. As a consequence of the high right-left correlation, the informative value of measuring a second ear in the same animal was, in our experiments, only 11% of that of the first one. No correlation could be found between the degree of skin pigmentation and the threshold elevation.
authors.affiliation: Department of Otolaryngology, Malmö General Hospital, University of Lund, Sweden.
authors.forename: J
authors.initials: J
authors.lastname: Grenner
authors.forename: P
authors.initials: P
authors.lastname: Nilsson
authors.forename: B
authors.initials: B
authors.lastname: Katbamna
mesh_terms: D000200:Action Potentials; D000704:Analysis of Variance; D000818:Animals; D001309:Auditory Threshold / Q000502:physiology*; D004423:Ear / Q000503:physiopathology*; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006168:Guinea Pigs; D006317:Hearing Loss, Noise-Induced / Q000503:physiopathology*; D008543:Melanins / Q000502:physiology; D009622:Noise / Q000009:adverse effects; D012880:Skin Pigmentation / Q000502:physiology
chemical_list: D008543:Melanins