title: Of mice and rats: key species variations in the sexual differentiation of brain and behavior.
abstract: Mice and rats are important mammalian models in biomedical research. In contrast to other biomedical fields, work on sexual differentiation of brain and behavior has traditionally utilized comparative animal models. As mice are gaining in popularity, it is essential to acknowledge the differences between these two rodents. Here we review neural and behavioral sexual dimorphisms in rats and mice, which highlight species differences and experimental gaps in the literature, that are needed for direct species comparisons. Moving forward, investigators must answer fundamental questions about their chosen organism, and attend to both species and strain differences as they select the optimal animal models for their research questions.
authors.affiliation: Neuroscience Graduate Program, University of Virginia, Charlottesville, VA, United States.
authors.forename: P J
authors.initials: PJ
authors.lastname: Bonthuis
authors.forename: K H
authors.initials: KH
authors.lastname: Cox
authors.forename: B T
authors.initials: BT
authors.lastname: Searcy
authors.forename: P
authors.initials: P
authors.lastname: Kumar
authors.forename: S
authors.initials: S
authors.lastname: Tobet
authors.forename: E F
authors.initials: EF
authors.lastname: Rissman
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D001921:Brain / Q000254:growth & development / Q000502:physiology*; D006801:Humans; D051379:Mice; D023421:Models, Animal; D051381:Rats; D012733:Sex Differentiation / Q000502:physiology*; D012726:Sexual Behavior, Animal / Q000502:physiology*; D013045:Species Specificity
references.citation: Brain Res. 1982 Oct;281(2):209-12
references.pmid: 7139351
references.citation: Behav Neurosci. 2000 Oct;114(5):923-33
references.pmid: 11085606
references.citation: Behav Neurosci. 2007 Apr;121(2):356-61
references.pmid: 17469925
references.citation: Horm Behav. 1991 Sep;25(3):323-41
references.pmid: 1937426
references.citation: Psychopharmacology (Berl). 2005 Jul;180(2):206-14
references.pmid: 15696326
references.citation: Biol Reprod. 1982 Dec;27(5):1174-80
references.pmid: 7159661
references.citation: Brain Res Mol Brain Res. 2000 Mar 29;76(2):191-204
references.pmid: 10762694
references.citation: Mol Cell Endocrinol. 1977 Oct;8(4):317-34
references.pmid: 924015
references.citation: Science. 1963 Jul 19;141(3577):273-4
references.pmid: 14000192
references.citation: Dev Psychobiol. 1979 May;12(3):231-8
references.pmid: 437362
references.citation: Physiol Behav. 1982 Aug;29(2):263-7
references.pmid: 7146131
references.citation: Science. 1965 Jan 15;147(3655):306-7
references.pmid: 17788218
references.citation: Eur J Neurosci. 2006 Jan;23(2):521-30
references.pmid: 16420459
references.citation: Proc Natl Acad Sci U S A. 1994 May 24;91(11):5212-6
references.pmid: 7515189
references.citation: Cancer Res. 1982 Aug;42(8 Suppl):3274s-3276s
references.pmid: 7083185
references.citation: Physiol Behav. 1983 Apr;30(4):613-6
references.pmid: 6878461
references.citation: J Endocrinol. 1978 Feb;76(2):241-9
references.pmid: 627818
references.citation: Behav Neurosci. 1993 Dec;107(6):1049-58
references.pmid: 8136058
references.citation: Eur J Neurosci. 2007 Apr;25(7):2182-90
references.pmid: 17419752
references.citation: J Neurochem. 1999 Sep;73(3):1200-5
references.pmid: 10461912
references.citation: Neuroscience. 1996 Sep;74(1):251-60
references.pmid: 8843090
references.citation: Neuroendocrinology. 2003 Jun;77(6):416-24
references.pmid: 12845227
references.citation: Endocrinology. 1978 Nov;103(5):1702-9
references.pmid: 570912
references.citation: Physiol Behav. 2003 Sep;79(4-5):633-41
references.pmid: 12954404
references.citation: J Neurosci. 2007 Aug 15;27(33):8826-35
references.pmid: 17699664
references.citation: Brain Res Dev Brain Res. 1996 Oct 23;96(1-2):281-4
references.pmid: 8922690
references.citation: Neurosci Biobehav Rev. 2002 Oct;26(6):665-78
references.pmid: 12479841
references.citation: J Neurosci. 2001 Apr 1;21(7):2474-80
references.pmid: 11264321
references.citation: Brain Res Dev Brain Res. 1997 May 20;100(1):117-20
references.pmid: 9174253
references.citation: Horm Behav. 1974 Jun;5(2):125-8
references.pmid: 4847181
references.citation: Science. 1964 Jul 31;145(3631):514-5
references.pmid: 14163780
references.citation: Brain Res Brain Res Rev. 1993 Jan-Apr;18(1):51-74
references.pmid: 8467350
references.citation: Biol Reprod. 1992 Oct;47(4):561-7
references.pmid: 1391342
references.citation: Dev Psychobiol. 1973 Jul;6(4):319-27
references.pmid: 4793361
references.citation: Pharmacol Biochem Behav. 2006 Apr;83(4):618-23
references.pmid: 16650888
references.citation: Horm Behav. 2006 Nov;50(4):579-88
references.pmid: 16876166
references.citation: Pharmacol Biochem Behav. 2005 Sep;82(1):228-35
references.pmid: 16168471
references.citation: Horm Behav. 1979 Aug;13(1):66-84
references.pmid: 521021
references.citation: Steroids. 1974 Apr;23(4):499-505
references.pmid: 4829342
references.citation: Horm Behav. 2006 Nov;50(4):589-601
references.pmid: 16870186
references.citation: J Endocrinol. 1962 Oct;25:175-82
references.pmid: 13969490
references.citation: Horm Behav. 1984 Jun;18(2):117-29
references.pmid: 6539747
references.citation: Brain Res Bull. 1993;32(2):185-9
references.pmid: 8348343
references.citation: Endocrinology. 1997 Jan;138(1):507-10
references.pmid: 8977441
references.citation: Nature. 1967 Oct 7;216(5110):88-9
references.pmid: 6069257
references.citation: J Comp Neurol. 2000 Dec 11;428(2):254-65
references.pmid: 11064365
references.citation: Endocrinology. 2003 May;144(5):2055-67
references.pmid: 12697714
references.citation: J Comp Physiol Psychol. 1969 Aug;68(4):490-7
references.pmid: 5388030
references.citation: Behav Brain Res. 1991 Jul 1;44(1):43-51
references.pmid: 1910570
references.citation: Neurosci Res. 2002 Jun;43(2):147-54
references.pmid: 12067750
references.citation: Genes Brain Behav. 2002 Jan;1(1):55-69
references.pmid: 12886950
references.citation: Horm Behav. 2009 Aug;56(2):254-63
references.pmid: 19450599
references.citation: Neurotoxicology. 2007 Jan;28(1):1-12
references.pmid: 17109964
references.citation: Proc Natl Acad Sci U S A. 1997 Feb 18;94(4):1476-81
references.pmid: 9037078
references.citation: Nat Neurosci. 2006 Feb;9(2):220-6
references.pmid: 16388309
references.citation: Behav Biol. 1972 Jun;7(3):321-34
references.pmid: 5063898
references.citation: Brain Res. 1990 Sep 3;526(2):303-7
references.pmid: 2257487
references.citation: Science. 1980 May 9;208(4444):597-9
references.pmid: 7367881
references.citation: Neuroscience. 2008 Apr 22;153(1):1-19
references.pmid: 18359574
references.citation: Horm Behav. 1997 Dec;32(3):176-83
references.pmid: 9454668
references.citation: Stroke. 2001 Apr;32(4):1028-35
references.pmid: 11283407
references.citation: Front Neuroendocrinol. 2005 Apr;26(1):7-26
references.pmid: 15862182
references.citation: Science. 2003 Feb 21;299(5610):1196-201
references.pmid: 12595684
references.citation: Nat Genet. 2007 Nov;39(11):1384-9
references.pmid: 17965714
references.citation: J Steroid Biochem. 1988 Sep;31(3):283-6
references.pmid: 3419158
references.citation: J Endocrinol. 1980 Oct;87(1):81-7
references.pmid: 7430918
references.citation: Eur J Endocrinol. 1995 Sep;133(3):366-74
references.pmid: 7581956
references.citation: J Comp Physiol Psychol. 1965 Apr;59:176-82
references.pmid: 14288340
references.citation: Nat Neurosci. 2004 Jun;7(6):643-50
references.pmid: 15156148
references.citation: Proc Natl Acad Sci U S A. 2005 Mar 22;102(12):4608-12
references.pmid: 15761056
references.citation: Horm Behav. 1997 Jun;31(3):232-43
references.pmid: 9213137
references.citation: J Neuroendocrinol. 2009 Mar;21(4):257-62
references.pmid: 19207809
references.citation: Physiol Behav. 1991 Jan;49(1):107-11
references.pmid: 2017462
references.citation: Brain Res Dev Brain Res. 1990 Nov 1;56(2):263-8
references.pmid: 2261686
references.citation: Proc Natl Acad Sci U S A. 1994 Jul 5;91(14):6468-72
references.pmid: 7517551
references.citation: J Neurobiol. 1999 May;39(2):249-63
references.pmid: 10235679
references.citation: Horm Behav. 1972 Mar;3(1):47-54
references.pmid: 4680506
references.citation: Proc Natl Acad Sci U S A. 2007 Apr 3;104(14):6084-9
references.pmid: 17389373
references.citation: Proc Natl Acad Sci U S A. 2004 Feb 10;101(6):1673-8
references.pmid: 14747651
references.citation: Endocrinology. 2006 Jan;147(1):415-20
references.pmid: 16239299
references.citation: Physiol Behav. 1970 Apr;5(4):407-11
references.pmid: 5535491
references.citation: Science. 1964 Jan 17;143(3603):212-8
references.pmid: 14077548
references.citation: Physiol Behav. 1977 Jul;19(1):35-9
references.pmid: 11803687
references.citation: J Comp Neurol. 2003 Nov 10;466(2):251-77
references.pmid: 14528452
references.citation: J Endocrinol. 1984 Jan;100(1):7-11
references.pmid: 6690645
references.citation: Dev Neurobiol. 2007 Sep 15;67(11):1511-9
references.pmid: 17525992
references.citation: Proc Natl Acad Sci U S A. 2002 Mar 5;99(5):3306-11
references.pmid: 11854469
references.citation: Horm Behav. 1986 Dec;20(4):445-51
references.pmid: 3793025
references.citation: FEBS Lett. 1996 Aug 19;392(1):49-53
references.pmid: 8769313
references.citation: J Endocrinol. 1966 Jan;34(1):131-2
references.pmid: 5900574
references.citation: Physiol Behav. 2009 May 25;97(2):151-6
references.pmid: 19254731
references.citation: J Neurosci. 2009 Aug 5;29(31):9714-8
references.pmid: 19657024
references.citation: Science. 1973 Aug 24;181(4101):770-2
references.pmid: 4724936
references.citation: Horm Behav. 1977 Dec;9(3):249-63
references.pmid: 611076
references.citation: Horm Behav. 2008 Nov;54(5):662-8
references.pmid: 18687334
references.citation: Brain Res Dev Brain Res. 2001 Aug 23;129(2):125-33
references.pmid: 11506857
references.citation: J Neurosci. 2004 Oct 20;24(42):9451-7
references.pmid: 15496681
references.citation: Neuro Endocrinol Lett. 2005 Dec;26(6):729-32
references.pmid: 16380686
references.citation: J Comp Neurol. 2002 Nov 25;453(4):336-44
references.pmid: 12389206
references.citation: J Neuroendocrinol. 2000 May;12(5):397-402
references.pmid: 10792577
references.citation: J Neurosci. 2000 Jun 1;20(11):4248-54
references.pmid: 10818161
references.citation: Proc Natl Acad Sci U S A. 2002 Apr 30;99(9):6376-81
references.pmid: 11972034
references.citation: Endocrinology. 2008 Jun;149(6):3054-61
references.pmid: 18308846
references.citation: Physiol Behav. 1999 Sep;67(3):401-8
references.pmid: 10497959
references.citation: J Biol Chem. 1990 May 25;265(15):8893-900
references.pmid: 2341409
references.citation: Cell. 2009 Oct 2;139(1):61-72
references.pmid: 19804754
references.citation: J Neurobiol. 2001 Jun 5;47(3):176-82
references.pmid: 11333399
references.citation: Endocrinology. 1983 May;112(5):1883-5
references.pmid: 6832075
references.citation: Dev Neurobiol. 2007 Sep 1;67(10):1371-81
references.pmid: 17638388
references.citation: Front Neuroendocrinol. 2008 Jan;29(1):1-16
references.pmid: 17720235
references.citation: J Neuroendocrinol. 2009 Mar;21(4):351-8
references.pmid: 19207807
references.citation: J Neurobiol. 2000 Feb 15;42(3):315-22
references.pmid: 10645971
references.citation: Eur J Neurosci. 2006 Mar;23(5):1234-40
references.pmid: 16553785
references.citation: Ann N Y Acad Sci. 2003 Dec;1007:251-62
references.pmid: 14993058
references.citation: J Endocrinol. 1986 Feb;108(2):281-5
references.pmid: 2936858
references.citation: Anim Behav. 1976 Feb;24(1):135-40
references.pmid: 944542
references.citation: Brain Res. 1984 Jun;316(2):289-91
references.pmid: 6467020
references.citation: Acta Physiol Scand Suppl. 1978;453:5-27
references.pmid: 274903
references.citation: Science. 1999 Oct 22;286(5440):716-20
references.pmid: 10531049
references.citation: Endocrinology. 2002 Oct;143(10):3727-39
references.pmid: 12239082
references.citation: J Neuroendocrinol. 2007 May;19(5):329-34
references.pmid: 17425607
references.citation: Exp Biol Med (Maywood). 2005 Jan;230(1):49-56
references.pmid: 15618125
references.citation: Anat Rec. 1967 Jan;157(1):79-86
references.pmid: 6030761
references.citation: Proc Natl Acad Sci U S A. 1997 Dec 9;94(25):14077-82
references.pmid: 9391155
references.citation: Dev Neurosci. 2009;31(4):318-31
references.pmid: 19546569
references.citation: Behav Brain Res. 2008 Aug 5;191(1):111-7
references.pmid: 18433893
references.citation: Exp Neurol. 1983 Feb;79(2):569-75
references.pmid: 6822281
references.citation: Horm Behav. 2009 Jan;55(1):68-75
references.pmid: 18793640
references.citation: Physiol Behav. 1971 Mar;6(3):223-8
references.pmid: 5166472
references.citation: J Comp Neurol. 1997 Dec 1;388(4):507-25
references.pmid: 9388012
references.citation: Neurosci Biobehav Rev. 2005 Apr;29(2):353-84
references.pmid: 15811504
references.citation: J Comp Neurol. 2000 Oct 23;426(3):441-67
references.pmid: 10992249
references.citation: J Physiol. 1965 Nov;181(2):379-400
references.pmid: 5893725
references.citation: Physiol Behav. 1987;39(5):599-605
references.pmid: 3588705
references.citation: J Neurosci. 2002 Oct 15;22(20):9104-12
references.pmid: 12388618
references.citation: Brain Res Dev Brain Res. 1999 Jun 2;115(2):171-82
references.pmid: 10407134
references.citation: Horm Behav. 2004 Nov;46(4):482-90
references.pmid: 15465535
references.citation: Peptides. 2009 Jan;30(1):94-102
references.pmid: 18789989
references.citation: Endocrinology. 2008 Aug;149(8):4142-50
references.pmid: 18467440
references.citation: Brain Res. 1987 Apr;429(2):295-300
references.pmid: 3567668
references.citation: Horm Behav. 1988 Sep;22(3):294-304
references.pmid: 3169695
references.citation: Chem Senses. 2006 Oct;31(8):753-62
references.pmid: 16901952
references.citation: J Comp Neurol. 2002 May 13;446(4):301-24
references.pmid: 11954031
references.citation: Horm Behav. 2009 May;55(5):589-96
references.pmid: 19446075
references.citation: J Neurosci. 2009 Apr 8;29(14):4461-70
references.pmid: 19357272
references.citation: Pharmacol Res. 2001 Jun;43(6):531-4
references.pmid: 11419961
references.citation: Behav Neurosci. 2008 Aug;122(4):876-84
references.pmid: 18729641
references.citation: Physiol Behav. 1987;39(5):625-8
references.pmid: 3588709
references.citation: J Endocrinol. 1976 Sep;70(3):409-20
references.pmid: 978102
references.citation: Horm Behav. 1976 Mar;7(1):105-38
references.pmid: 819345
references.citation: Horm Behav. 1979 Feb;12(1):12-9
references.pmid: 478444
references.citation: Endocrinology. 2002 Feb;143(2):607-14
references.pmid: 11796516
references.citation: Brain Res Dev Brain Res. 2005 Jun 9;157(1):34-41
references.pmid: 15939083
references.citation: Brain Res Mol Brain Res. 2000 Jan 10;75(1):89-95
references.pmid: 10648891
references.citation: Physiol Behav. 2009 Aug 4;98(1-2):25-30
references.pmid: 19375435
references.citation: Neuroscience. 1998 Jul;85(2):361-73
references.pmid: 9622236
references.citation: Physiol Behav. 1990 Sep;48(3):447-50
references.pmid: 2267253
references.citation: Neurosci Biobehav Rev. 1979 Winter;3(4):265-84
references.pmid: 120519
references.citation: Physiol Behav. 1991 Mar;49(3):549-55
references.pmid: 2062933
references.citation: Mol Endocrinol. 1991 Apr;5(4):573-81
references.pmid: 1681426
references.citation: J Endocrinol. 1982 Mar;92(3):419-24
references.pmid: 7040585
references.citation: Endocrinology. 1998 Aug;139(8):3658-61
references.pmid: 9681521
references.citation: Psychopharmacology (Berl). 1999 Nov;147(1):5-7
references.pmid: 10591855
references.citation: Physiol Behav. 1983 Sep;31(3):385-9
references.pmid: 6635009
references.citation: Horm Behav. 2002 Sep;42(2):158-71
references.pmid: 12367569
references.citation: Biochem Biophys Res Commun. 1998 Nov 18;252(2):445-9
references.pmid: 9826549
references.citation: Horm Behav. 1995 Jun;29(2):191-206
references.pmid: 7557922
references.citation: J Endocrinol. 2001 Mar;168(3):455-63
references.pmid: 11241177
references.citation: Behav Neurosci. 2008 Oct;122(5):963-73
references.pmid: 18823153
references.citation: Horm Behav. 1982 Dec;16(4):443-54
references.pmid: 6897645
references.citation: Endocrinology. 1998 Oct;139(10):4252-63
references.pmid: 9751507
references.citation: Endocrinology. 1994 Oct;135(4):1705-8
references.pmid: 7925135
references.citation: Endocrinology. 1993 Aug;133(2):433-9
references.pmid: 8344188
references.citation: Science. 1980 Jan 18;207(4428):328-9
references.pmid: 7188648
references.citation: Endocrinology. 1980 Jan;106(1):306-16
references.pmid: 7349961
references.citation: Neuroscience. 2006;138(3):921-8
references.pmid: 16338079
references.citation: Horm Behav. 1982 Sep;16(3):251-8
references.pmid: 7173829
references.citation: Physiol Behav. 1996 Nov;60(5):1347-54
references.pmid: 8916193
references.citation: Eur J Neurosci. 2007 Jul;26(2):463-75
references.pmid: 17623023
references.citation: BMC Neurosci. 2009 Jul 15;10:78
references.pmid: 19604366
references.citation: Anat Rec. 1967 Jan;157(1):97-104
references.pmid: 6067691
references.citation: Horm Behav. 2004 Jun;46(1):1-10
references.pmid: 15215036
references.citation: Cerebellum. 2003;2(4):242-62
references.pmid: 14964684
references.citation: Cell. 1974 Nov;3(3):235-42
references.pmid: 4474059
references.citation: J Androl. 2001 Sep-Oct;22(5):825-30
references.pmid: 11545296
references.citation: Behav Neurosci. 2009 Apr;123(2):369-81
references.pmid: 19331460
references.citation: Dev Neurobiol. 2008 Jun;68(7):981-95
references.pmid: 18418875
references.citation: Nature. 2001 Sep 13;413(6852):211-8
references.pmid: 11557990
references.citation: Neuroendocrinology. 1985 Jun;40(6):501-10
references.pmid: 2861581
references.citation: Endocrinology. 1959 Sep;65:369-82
references.pmid: 14432658
references.citation: J Comp Neurol. 1990 Aug 1;298(1):1-22
references.pmid: 2170466
references.citation: FASEB J. 2004 Oct;18(13):1568-70
references.pmid: 15289439
references.citation: Anat Rec. 1967 Feb;157(2):173-80
references.pmid: 6034297
references.citation: Behav Brain Res. 2009 Jan 23;196(2):317-22
references.pmid: 18950659
references.citation: Physiol Behav. 1994 Sep;56(3):535-41
references.pmid: 7972405
references.citation: Brain Res. 2006 Dec 18;1126(1):66-75
references.pmid: 16963001
references.citation: Brain Res Mol Brain Res. 1992 Apr;13(3):251-61
references.pmid: 1317497
references.citation: Horm Behav. 2008 Sep;54(4):557-64
references.pmid: 18582470
references.citation: Fertil Steril. 1975 Sep;26(9):939-44
references.pmid: 1183649
references.citation: Mol Cell Endocrinol. 2002 Dec 30;198(1-2):61-7
references.pmid: 12573815
references.citation: Science. 1975 Oct 31;190(4213):484-6
references.pmid: 1174387
references.citation: Brain Res Mol Brain Res. 1999 Nov 10;73(1-2):60-7
references.pmid: 10581398
references.citation: Eur J Neurosci. 1997 Jan;9(1):120-7
references.pmid: 9042576
references.citation: J Neuroendocrinol. 2009 Mar;21(4):421-6
references.pmid: 19207815
references.citation: J Neuroendocrinol. 2000 Feb;12(2):103-10
references.pmid: 10718905
references.citation: Science. 2002 Feb 22;295(5559):1493-500
references.pmid: 11823606
references.citation: Reprod Fertil Dev. 2008;20(5):557-62
references.pmid: 18577352
references.citation: J Neuroendocrinol. 2009 Mar;21(4):393-9
references.pmid: 19207822
references.citation: J Endocrinol. 1977 Feb;72(2):135-41
references.pmid: 845532
references.citation: Behav Neurosci. 1993 Jun;107(3):480-7
references.pmid: 8329137
references.citation: Physiol Behav. 2002 Mar;75(3):337-46
references.pmid: 11897260
references.citation: Arch Int Physiol Biochim Biophys. 1992 Mar-Apr;100(2):127-31
references.pmid: 1379488
references.citation: Brain Res Dev Brain Res. 2003 Oct 10;145(1):117-39
references.pmid: 14519499
references.citation: J Comp Neurol. 2005 Nov 28;492(4):456-68
references.pmid: 16228996
references.citation: Horm Behav. 1974 Mar;5(1):19-31
references.pmid: 4857571
references.citation: Science. 1989 Oct 13;246(4927):257-60
references.pmid: 2508225
references.citation: Proc Natl Acad Sci U S A. 1999 Oct 26;96(22):12887-92
references.pmid: 10536018
references.citation: Biol Reprod. 2006 Sep;75(3):469-76
references.pmid: 16738224
references.citation: Physiol Behav. 2004 Nov 15;83(2):217-32
references.pmid: 15488541
references.citation: Dev Psychobiol. 1974 Sep;7(5):483-8
references.pmid: 4426475
references.citation: Endocrinology. 2005 Apr;146(4):1650-73
references.pmid: 15618360
references.citation: Physiol Behav. 1974 Dec;13(6):803-8
references.pmid: 4445285
references.citation: J Neuroendocrinol. 2009 Mar;21(4):370-6
references.pmid: 19226350
references.citation: Front Neuroendocrinol. 2006 Sep;27(3):340-59
references.pmid: 17014900
references.citation: Endocrinology. 1978 Dec;103(6):1985-91
references.pmid: 748030
references.citation: J Neuroendocrinol. 2003 Oct;15(10):978-83
references.pmid: 12969243
references.citation: Cerebellum. 2002 Dec;1(4):241-58
references.pmid: 12879963
references.citation: Eur J Neurosci. 2008 Jan;27(2):423-31
references.pmid: 18215238
references.citation: Toxicol Sci. 2004 Dec;82(2):570-6
references.pmid: 15456915
references.citation: Neuroscience. 2006;138(3):987-95
references.pmid: 16310319
references.citation: Chem Senses. 2006 May;31(4):315-23
references.pmid: 16484502
references.citation: Physiol Behav. 1990 Oct;48(4):555-60
references.pmid: 2075207
references.citation: J Endocrinol. 1978 Feb;76(2):233-40
references.pmid: 627817
references.citation: J Comp Neurol. 2007 Jul 20;503(3):392-406
references.pmid: 17503490