title: Multifeatural shape processing in rats engaged in invariant visual object recognition.
abstract: The ability to recognize objects despite substantial variation in their appearance (e.g., because of position or size changes) represents such a formidable computational feat that it is widely assumed to be unique to primates. Such an assumption has restricted the investigation of its neuronal underpinnings to primate studies, which allow only a limited range of experimental approaches. In recent years, the increasingly powerful array of optical and molecular tools that has become available in rodents has spurred a renewed interest for rodent models of visual functions. However, evidence of primate-like visual object processing in rodents is still very limited and controversial. Here we show that rats are capable of an advanced recognition strategy, which relies on extracting the most informative object features across the variety of viewing conditions the animals may face. Rat visual strategy was uncovered by applying an image masking method that revealed the features used by the animals to discriminate two objects across a range of sizes, positions, in-depth, and in-plane rotations. Noticeably, rat recognition relied on a combination of multiple features that were mostly preserved across the transformations the objects underwent, and largely overlapped with the features that a simulated ideal observer deemed optimal to accomplish the discrimination task. These results indicate that rats are able to process and efficiently use shape information, in a way that is largely tolerant to variation in object appearance. This suggests that their visual system may serve as a powerful model to study the neuronal substrates of object recognition.
authors.affiliation: Visual Neuroscience Laboratory, International School for Advanced Studies, 34136 Trieste, Italy.
authors.forename: Alireza
authors.initials: A
authors.lastname: Alemi-Neissi
authors.forename: Federica Bianca
authors.initials: FB
authors.lastname: Rosselli
authors.forename: Davide
authors.initials: D
authors.lastname: Zoccolan
mesh_terms: D000818:Animals; D003198:Computer Simulation; D003216:Conditioning, Operant; D004192:Discrimination, Psychological; D005556:Form Perception / Q000502:physiology*; D008297:Male; D008954:Models, Biological; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010775:Photic Stimulation; D051381:Rats; D020318:Rats, Long-Evans; D011930:Reaction Time / Q000502:physiology; D021641:Recognition, Psychology / Q000502:physiology*; D014795:Visual Pathways / Q000502:physiology*
references.citation: J Exp Biol. 2001 Jul;204(Pt 14):2439-46
references.pmid: 11511659
references.citation: Curr Biol. 2007 Feb 20;17(4):336-40
references.pmid: 17275301
references.citation: Vision Res. 2001 Aug;41(17):2261-71
references.pmid: 11448718
references.citation: Eur J Neurosci. 1989 Jan;1(6):639-646
references.pmid: 12106121
references.citation: J Neurosci. 2007 Nov 7;27(45):12292-307
references.pmid: 17989294
references.citation: PLoS Comput Biol. 2009 Nov;5(11):e1000579
references.pmid: 19956750
references.citation: Neuron. 2011 Dec 22;72(6):889-92
references.pmid: 22196324
references.citation: Neuron. 2010 Feb 25;65(4):472-9
references.pmid: 20188652
references.citation: J Neurosci. 2005 Sep 7;25(36):8150-64
references.pmid: 16148223
references.citation: J Vis. 2011 Mar 31;11(3):
references.pmid: 21454857
references.citation: J Neurosci. 2011 Dec 14;31(50):18506-21
references.pmid: 22171051
references.citation: Neuron. 2011 Dec 22;72(6):1025-39
references.pmid: 22196337
references.citation: Nat Rev Neurosci. 2009 May;10(5):360-72
references.pmid: 19352403
references.citation: Curr Opin Neurobiol. 2012 Feb;22(1):45-53
references.pmid: 22237048
references.citation: Front Neurosci. 2010 Nov 29;4:193
references.pmid: 21152259
references.citation: Vis Neurosci. 2006 Sep-Oct;23(5):765-78
references.pmid: 17020632
references.citation: J Neurosci. 2012 Jan 4;32(1):21-34
references.pmid: 22219267
references.citation: Curr Biol. 2012 Jan 10;22(1):50-5
references.pmid: 22209530
references.citation: Cereb Cortex. 1991 Jan-Feb;1(1):1-47
references.pmid: 1822724
references.citation: Behav Brain Res. 2002 Nov 15;136(2):339-48
references.pmid: 12429395
references.citation: Annu Rev Neurosci. 1996;19:109-39
references.pmid: 8833438
references.citation: Proc Natl Acad Sci U S A. 2009 May 26;106(21):8748-53
references.pmid: 19429704
references.citation: Invest Ophthalmol Vis Sci. 2004 Jun;45(6):1854-62
references.pmid: 15161850
references.citation: J Neurosci. 2011 Aug 3;31(31):11351-61
references.pmid: 21813694
references.citation: Learn Mem. 2006 May-Jun;13(3):287-97
references.pmid: 16705141
references.citation: Nat Neurosci. 2008 Jul;11(7):749-51
references.pmid: 18552841
references.citation: Trends Neurosci. 2011 Sep;34(9):464-73
references.pmid: 21840069
references.citation: J Neurosci Methods. 2000 Apr 15;97(2):103-10
references.pmid: 10788664
references.citation: J Neurosci. 2011 Feb 2;31(5):1905-18
references.pmid: 21289200
references.citation: PLoS Comput Biol. 2008 Jan;4(1):e27
references.pmid: 18225950
references.citation: Psychol Sci. 2002 Sep;13(5):402-9
references.pmid: 12219805
references.citation: J Neurosci Methods. 2007 May 15;162(1-2):84-90
references.pmid: 17289151
references.citation: Neuron. 2012 Feb 9;73(3):415-34
references.pmid: 22325196
references.citation: Proc Natl Acad Sci U S A. 2007 Apr 10;104(15):6424-9
references.pmid: 17404214
references.citation: J Neurosci. 2006 Jul 19;26(29):7680-92
references.pmid: 16855096
references.citation: Proc Natl Acad Sci U S A. 2012 May 8;109(19):7241-4
references.pmid: 22509011
references.citation: J Exp Psychol Anim Behav Process. 2005 Jul;31(3):376-82
references.pmid: 16045392
references.citation: Neuron. 2000 Aug;27(2):205-18
references.pmid: 10985342
references.citation: J Neurophysiol. 2012 Feb;107(3):758-65
references.pmid: 22049334
references.citation: Physiol Rev. 2008 Jan;88(1):59-89
references.pmid: 18195083
references.citation: Nature. 2005 Feb 10;433(7026):597-603
references.pmid: 15660108
references.citation: Annu Rev Neurosci. 1996;19:577-621
references.pmid: 8833455
references.citation: J Neurophysiol. 2009 Jul;102(1):360-76
references.pmid: 19439676
references.citation: J Vis. 2011 May 02;11(5):
references.pmid: 21536726
references.citation: Neuron. 2006 Aug 17;51(4):399-407
references.pmid: 16908406
references.citation: J Neurosci. 2010 Sep 29;30(39):12978-95
references.pmid: 20881116
references.citation: Proc Natl Acad Sci U S A. 2009 Nov 17;106(46):19557-62
references.pmid: 19889973
references.citation: J Vis. 2008 Feb 22;8(2):9.1-15
references.pmid: 18318635
references.citation: Trends Cogn Sci. 2008 Dec;12(12):466-73
references.pmid: 18951831
references.citation: Neuron. 2011 Dec 22;72(6):1040-54
references.pmid: 22196338
references.citation: Curr Biol. 2006 Apr 18;16(8):814-20
references.pmid: 16631590
references.citation: J Neurosci. 2008 Jul 23;28(30):7520-36
references.pmid: 18650330
references.citation: J Neurosci. 2010 Apr 28;30(17):5912-26
references.pmid: 20427651
references.citation: Vis Neurosci. 2001 Jul-Aug;18(4):641-56
references.pmid: 11829310