The effect of a reversible, unilateral hearing loss on 2-deoxyglucose (2-DG) uptake in the central auditory system was studied using young gerbils. All animals had a unilateral conductive hearing loss (CHL), induced by atresia, on postnatal day 21 (P21). One week later, on P28, animals had their atresia repaired (CHL/R), or not repaired (CHL/NR), and CHL/NR animals entered the 2-DG experiments. CHL/R animals were allowed a 1-week period of restored binaural hearing experience prior to entering 2-DG experiments on P35. Animals in each group were injected with 2-DG and exposed to ambient sounds for 45 min prior to sacrifice. Uptake of 2-DG was measured in the anteroventral cochlear nucleus (AVCN), the medial superior olive (MSO), and the inferior colliculus (IC) on both sides of the brain. In CHL/NR animals, there were significant differences in uptake between the AVCN, MSO, and IC ipsilateral versus contralateral to the manipulated ear, indicating an imbalance in ascending afferent activity. In CHL/R animals, there were no significant differences, suggesting that 1 week after CHL repair, the appearance of balanced afferent activity had been restored.

Keywords:
Gerbil, 2-Deoxyglucose, Cochlear nucleus, Medial superior olive, Inferior colliculus, Atresia
1.
Benson CG, Gross JS, Suneja SK, Potashner SJ: Synaptophysin immunoreactivity in the cochlear nucleus after unilateral cochlear or ossicular removal. Synapse 1997;25:243–257.
2.
Blatchley BJ, Williams JE, Coleman JR: Age-dependent effects of acoustic deprivation on spherical cells of the rat anteroventral cochlear nucleus. Exp Neurol 1983;80:81–93.
3.
Brugge JF, Orman SS, Coleman JR, Chan JC, Phillips DP: Binaural interactions in cortical area AI of cats reared with unilateral atresia of the external ear canal. Hear Res 1985;20:275–287.
4.
Clements M, Kelly JB: Auditory spatial responses of young guinea pigs (Cavia porcellus) during and after ear blocking. J Comp Physiol Psychol 1978;92:34–44.
5.
Clopton BM, Silverman MS: Changes in latency and duration of neural responding following developmental auditory deprivations. Exp Brain Res 1978;32:39–47.
6.
Coleman JR, O’Connor P: Effects of monaural and binaural sound deprivation on cell development in the anteroventral cochlear nucleus of rats. Exp Neurol 1979;64:553–566.
7.
Cook RD, Hung TY, Miller RL, Smith DW, Tucci DL: Effects of conductive hearing loss on auditory nerve activity in gerbil. Hear Res 2002;164:127–137.
8.
Feng AS, Rogowski BA: Effects of monaural and binaural occlusion on the morphology of neurons in the medial superior olivary nucleus of the rat. Brain Res 1980;189:530–534.
9.
Ferguson MO, Cook RD, Hall JW, Grose JH, Pillsbury HC: Chronic conductive hearing loss in adults. Arch Otolaryngol Head Neck Surg 1998;124:678–685.
10.
Finck A, Schneck CD, Hartman AF: Development of cochlear function in the neonate Mongolian gerbil (Meriones unguiculatus). J Comp Physiol Psychol 1972;78:375–380.
11.
Folsom RC, Weber BA, Thompson G: Auditory brainstem responses in children with early recurrent middle ear disease. Ann Otol Rhinol Laryngol 1983;92:249–253.
12.
Gravel JS, Wallace IF: Listening and language at 4 years of age: effects of early otitis media. J Speech Hear Res 1992;35:588–595.
13.
Gunnarson AD, Finitzo T: Conductive hearing loss in infancy: effects on later auditory brainstem electrophysiology. J Speech Hear Res 1991;34:1207–1215.
14.
Hall JW, Derlacki EL: Effect of conductive hearing loss and middle ear surgery on binaural hearing. Ann Otol Rhinol Laryngol 1986;95:525–530.
15.
Hall JW, Derlacki EL: Binaural hearing after middle ear surgery: masking-level differences for interaural time and amplitude cues. Audiology 1988;27:89–98.
16.
Hall JW, Grose JH, Pillsbury HC: Long-term effects of chronic otitis media on binaural hearing in children. Arch Otolaryngol Head Neck Surg 1995;121:847–852.
17.
Hartley DE, Moore DR: Effects of conductive hearing loss on temporal aspects of sound transmission through the ear. Hear Res 2003;177:53–63.
18.
Hutson KA, Durham D, Tucci DL: Consequences of unilateral hearing loss: time dependent regulation of protein synthesis in auditory brainstem nuclei. Hear Res 2007;233:124–134.
19.
Hutson KA, Durham D, Imig T, Tucci DL: Consequences of unilateral hearing loss: cortical adjustment to unilateral deprivation. Hear Res 2008;237:19–31.
20.
Kelly JB, Potash M: Directional responses to sounds in young gerbils (Meriones unguiculatus). J Comp Psychol 1986;100:37–45.
21.
Keuroghlian AS, Knudsen EI: Adaptive auditory plasticity in developing and adult animals. Prog Neurobiol 2007;82:109–121.
22.
Killackey HP, Ryugo DK: Effects of neonatal peripheral auditory system damage on the structure of the inferior colliculus of the rat. Anat Rec 1977;187:624.
23.
Knudsen EI: Mechanisms of experience-dependent plasticity in the auditory localization pathway of the barn owl. J Comp Physiol 1999;185:305–321.
24.
Knudsen EI: Instructed learning in the auditory localization pathway of the barn owl. Nature 2002;417:322–328.
25.
Knudsen EI, Knudsen PF, Esterly SD: A critical period for the recovery of sound localization accuracy following monaural occlusion in the barn owl. J Neurosci 1984;4:1012–1020.
26.
Koehler S, Oldakowski M, Bledsoe S, Tucci D, Zhou J, Shore S: Ventral cochlear nucleus responses to contralateral sound are mediated by CN-commissural and olivocochlear pathways. 30th Annu Meet Assoc Res Otolaryngol, Denver, 2007.
27.
Lieu JE: Speech-language and educational consequences of unilateral hearing loss in children. Arch Otolaryngol Head Neck Surg 2004;130:524–530.
28.
Moore DR, Hine JE, Jiang ZD, Matsuda H, Parsons CH, King AJ: Conductive hearing loss produces a reversible binaural hearing impairment. J Neurosci 1999;19:8704–8711.
29.
Moore DR, Hutchings ME, King AJ, Kowalchuk NE: Auditory brain stem of the ferret: some effects of rearing with a unilateral ear plug on the cochlea, cochlear nucleus, and projections to the inferior colliculus. J Neurosci 1989;9:1213–1222.
30.
Moore DR, Irvine DF: Plasticity of binaural interaction in the cat inferior colliculus. Brain Res 1981;208:198–202.
31.
Nudo RJ, Masterton RB: 2-Deoxyglucose studies of stimulus coding in the brainstem auditory system of the cat; in Neff WD (ed): Contributions to Sensory Physiology. New York, Academic Press, 1984, vol 8, pp 79–97.
32.
Nudo RJ, Masterton RB: Stimulation-induced [14C]2-deoxyglucose labeling of synaptic activity in the central auditory system. J Comp Neurol 1986;245:553–565.
33.
Pasic TR, Moore DR, Rubel EW: Effect of altered neuronal activity on cell size in the medial nucleus of the trapezoid body and ventral cochlear nucleus of the gerbil. J Comp Neurol 1994;348:111–120.
34.
Pasic TR, Rubel EW: Rapid changes in cochlear nucleus cell size following blockade of auditory nerve electrical activity in gerbils. J Comp Neurol 1989;283:474–480.
35.
Pasic TR, Rubel EW: Cochlear nucleus cell size is regulated by auditory nerve electrical activity. Otolaryngol Head Neck Surg 1991;104:6–13.
36.
Pillsbury HC, Grose JH, Hall JW: Otitis media with effusion in children: binaural hearing before and after corrective surgery. Arch Otolaryngol Head Neck Surg 1991;117:718–723.
37.
Potash M, Kelly J: Development of directional responses to sounds in the rat (Rattus norvegicus). J Comp Physiol Psychol 1980;94:864–877.
38.
Potashner SJ, Suneja SK, Benson CG: Regulation of D-aspartate release and uptake in adult brain stem auditory nuclei after unilateral middle ear ossicle removal and cochlear ablation. Exp Neurol 1997;148:222–235.
39.
Richter K, Hess A, Scheich H: Functional mapping of transsynaptic effects of local manipulation of inhibition in gerbil auditory cortex. Brain Res 1999;831:184–199.
40.
Ryan AF, Woolf NK, Sharp FR: Tonotopic organization in the central auditory pathway of the Mongolian gerbil: a 2-deoxyglucose study. J Comp Neurol 1982;207:369–380.
41.
Ryan AF, Woolf NK: Development of the lower auditory system in the gerbil; in Romand R (ed): Development of the Auditory and Vestibular Systems 2. Amsterdam, Elsevier, 1993, pp 243–271.
42.
Schönweiler R, Ptok M, Radü HJ: A cross-sectional study of speech- and language-abilities of children with normal hearing, mild fluctuating conductive hearing loss, or moderate to profound sensoneurinal hearing loss. Int J Pediatr Otorhinolaryngol 1998;44:251–258.
43.
Sharp FR, Ryan AF, Goodwin P, Woolf NK: Increasing intensities of wide band noise increase [14C]2-deoxyglucose uptake in gerbil central auditory system. Brain Res 1981;230:87–96.
44.
Silverman MS, Clopton BM: Plasticity of binaural interaction. 1. Effect of early auditory deprivation. J Neurophysiol 1977a;40:1266–1274.
45.
Silverman MS, Clopton BM: Plasticity of binaural interaction. 2. Critical period and changes in midline response. J Neurophysiol 1977b;40:1275–1280.
46.
Smith ZD, Gray L, Rubel EW: Afferent influences on brainstem auditory nuclei of the chicken: n. laminaris dendritic length following monaural conductive hearing loss. J Comp Neurol 1983;220:199–205.
47.
Sperling NM, Patel N: A patient-benefit evaluation of unilateral congenital conductive hearing loss presenting in adulthood: should it be repaired? Laryngoscope 1999;109:1386–1391.
48.
Stuermer IW, Scheich H: Early unilateral auditory deprivation increases 2-deoxyglucose uptake in contralateral auditory cortex of juvenile Mongolian gerbils. Hear Res 2000;146:185–199.
49.
Sumner CJ, Tucci DL, Shore SE: Response of ventral cochlear nucleus neurons to contralateral sound after conductive hearing loss. J Neurophysiol 2005;94:4234–4243.
50.
Suneja SK, Postashner SJ, Benson CG: Plastic changes in glycine and GABA release and uptake in adult brain stem auditory nuclei after unilateral middle ear ossicle removal and cochlear ablation. Exp Neurol 1998;151:273–288.
51.
Tucci DL, Cant NB, Durham D: Conductive hearing loss results in a decrease in central auditory system activity in the young gerbil. Laryngoscope 1999;109:1359–1371.
52.
Tucci DL, Cant NB, Durham D: Conductive hearing loss results in changes in cytochrome oxidase activity in gerbil central auditory system. J Assoc Res Otolaryngol 2001;3:89–106.
53.
Webster DB: A critical period during postnatal auditory development of mice. Int J Pediatr Otorhinolaryngol 1983;6:107–118.
54.
Wilmington D, Gray L, Jahrsdoerfer R: Binaural processing after corrected congenital unilateral conductive hearing loss. Hear Res 1994;74:99–114.
55.
Woolf NK, Ryan AF: The development of auditory function in the cochlea of the Mongolian gerbil. Hear Res 1984;13:277–283.
56.
Woolf NK, Ryan AF: Ontogeny of neuronal discharge patterns in the ventral cochlear nucleus of the Mongolian gerbil. Brain Res 1985;17:131–147.
57.
Xu L, Jen PH: The effect of monaural middle ear destruction on postnatal development of auditory response properties of mouse inferior colliculus neurons. Hear Res 2001;159:1–13.
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