title: On the similarities and differences of non-traumatic sound exposure during the critical period and in adulthood.
abstract: There is an almost dogmatic view of the different effects of moderate-level sound stimulation in neonatal vs. adult animals. It is often stated that exposure in neonates results in an expansion of the cortical area that responds to the frequencies present in the sound, being either pure tones or frequency modulated sounds. In contrast, recent findings on stimulating adult animals for a sufficiently long time with similar sounds show a contraction of the cortical region responding to those sounds. In this review I will suggest that most neonatal animal results have been wrongly interpreted (albeit generally not by the original authors) and that the changes caused in the critical period (CP) and in adulthood are very similar. Thus, the mechanisms leading to the cortical map changes appear to be similar in the CP and in adulthood. Despite this similarity, the changes induced in the CP are occurring faster and are generally permanent (unless extensive training paradigms to revert the changes are involved), whereas in adults the induction is slower and a slow recovery (months) to pre-exposure conditions takes place.
authors: Department of Physiology and Pharmacology, Department of Psychology, University of Calgary Calgary, AB, Canada.
authors: Jos J
authors: JJ
authors: Eggermont
keywords: animal; auditory cortex; human; plasticity; tonotopic map
references: Ear Hear. 2008 Dec;29(6):819-29
references: 18941413
references: Psychol Sci. 2000 Mar;11(2):153-8
references: 11273423
references: Nat Neurosci. 2001 Nov;4(11):1123-30
references: 11687817
references: Audiol Neurootol. 2001 Nov-Dec;6(6):363-80
references: 11847464
references: J Neurosci. 2009 Nov 11;29(45):14077-85
references: 19906956
references: Biol Psychol. 2009 Jul;81(3):135-43
references: 19482230
references: Hear Res. 2013 Feb;296:121-30
references: 23154196
references: Proc Natl Acad Sci U S A. 2002 Feb 19;99(4):2309-14
references: 11842227
references: N Engl J Med. 2005 Jan 6;352(1):9-19
references: 15635108
references: Ear Hear. 2012 May-Jun;33(3):305-14
references: 22343545
references: J Acoust Soc Am. 1976 Jan;59(1):160-5
references: 1249315
references: J Neurosci. 2012 Mar 21;32(12):4212-23
references: 22442083
references: Hear Res. 2012 Jul;289(1-2):1-12
references: 22575207
references: Front Syst Neurosci. 2012 Sep 11;6:65
references: 22973201
references: Proc Natl Acad Sci U S A. 2004 May 4;101(18):7170-4
references: 15118079
references: Psychophysiology. 2004 Nov;41(6):875-81
references: 15563340
references: Hear Res. 2011 Jul;277(1-2):117-26
references: 21316436
references: Neurosci Biobehav Rev. 2011 Nov;35(10):2117-28
references: 21315757
references: Prog Neurobiol. 2007 Jun;82(3):109-21
references: 17493738
references: Proc Natl Acad Sci U S A. 2007 Oct 2;104(40):15935-40
references: 17895375
references: Nat Neurosci. 2008 Aug;11(8):957-65
references: 18604205
references: J Neurosci. 2007 Jan 3;27(1):180-9
references: 17202485
references: Scand J Work Environ Health. 1990;16 Suppl 1:29-38
references: 2189217
references: J Neurosci. 2013 Mar 27;33(13):5542-52
references: 23536069
references: Hear Res. 2009 Nov;257(1-2):24-40
references: 19647789
references: Hear Res. 2010 Mar;261(1-2):30-5
references: 20036723
references: J Acoust Soc Am. 1978 Feb;63(2):442-55
references: 670542
references: Science. 2003 Apr 18;300(5618):498-502
references: 12702879
references: Hear Res. 2010 Sep 1;268(1-2):151-62
references: 20630476
references: Science. 1983 Nov 4;222(4623):516-8
references: 6623091
references: Acta Paediatr. 1999 May;88(5):557-62
references: 10426181
references: Nat Commun. 2012 May 15;3:843
references: 22588305
references: Nat Neurosci. 2006 Jul;9(7):932-9
references: 16783369