Visual perception deficits in albinotic mammals - ferrets (Mustella putoriius furo) and rats (Rattus norvegiicus; strains Wistar and Long-Evans) [Elektronische Ressource] = Visuelle Wahrnehmungsdefizite albinotischer Säuger - Frettchen (Mustela putorius furo) und Ratten (Rattus norvegicus; Stämme Wistar und Long-Evans) / vorgelegt von Daniela Hupfeld

Hupfeld

Informations

• Publié par: ruhr-universitat_bochum
• Publié le: 01 janvier 2005
• Nombre de lectures: 33
• Langue: Deutsch
• Poids de l'ouvrage: 22 Mo

Extrait

VViissuuaall ppeerrcceeppttiioonn ddeeffiicciittss iinn aallbbiinnoottiicc mmaammmmaallss ––
ferrets (Mustela putorius furo) and rats (Rattus
norvegicus; strains Wistar and Long-Evans)


Visuelle Wahrnehmungsdefizite albinotischer Säuger – Frettchen
(Mustela putorius furo) und Ratten (Rattus norvegicus; Stämme
Wistar und Long-Evans)




Dissertation
zur Erlangung des Grades eines
Doktors der Naturwissenschaften
der Fakultät für Biologie
an der Ruhr-Universität Bochum



angefertigt am
Lehrstuhl für Allgemeine Zoologie und Neurobiologie

vorgelegt von Daniela Hupfeld
Lünen
2005


I




















Dissertation eingereicht am 15. 04. 2005

Betreuer: Prof. Dr. K.-P. Hoffmann
Lehrstuhl für Allgemeine Zoologie & Neurobiologie

Korefferent: Prof Dr. W. Kirchner
AG für Verhaltensbiologie & Didaktik der Biologie

Dekan: Prof. Dr. T. Stützel
Lehrstuhl für Spezielle Botanik



Content
1 General introduction ........................................................................................1
1.1 Albinism....................................................................................................1
1.1.1 Genotypes and phenotypes...............................................................2
1.1.2 Molecular biology of albinism ............................................................2
1.2 Effects of albinism on vision .....................................................................4
1.2.1 Retina................................................................................................4
1.2.2 Cell gradients.....................................................................................5
1.2.3 Retinal projections to higher visual centres .......................................6
1.2.4 Stereopsis .........................................................................................9
1.3 Oculomotor reactions..............................................................................10
1.3.1 Neuronal substrate for oculomotor reactions...................................11
1.4 Visual motion perception ........................................................................12
1.5 The rat ....................................................................................................13
1.5.1 Laboratory rat strains.......................................................................13
1.5.2 Visual system of the rat ...................................................................14
1.5.3 Retina..............................................................................................14
1.5.4 Optokinetic system and behaviour...................................................15
1.5.5 Higher visual centres.......................................................................16
1.6 The ferret................................................................................................18
1.6.1 Visual system of the ferret ...............................................................18
1.6.2 Retina..............................................................................................19
1.6.3 Optokinetic system ..........................................................................20
1.6.4 Higher visual centres.......................................................................21
1.7 Aim of the study......................................................................................23
2 Visual motion perception in Wistar and Long-Evans rats...............................25
2.1 Animals...................................................................................................25
2.2 Setup ......................................................................................................25
2.3 Procedure...............................................................................................26
2.3.1 Handshaping ...................................................................................26
2.3.2 Discrimination training .....................................................................27
2.3.3 Coherence discrimination ................................................................27
2.4 Stimuli.....................................................................................................28
I 2.5 Analysis ..................................................................................................30
2.6 Results....................................................................................................31
2.6.1 Visual discrimination and coherence detection................................31
2.6.2 Coherence threshold .......................................................................32
2.7 Conclusions............................................................................................33
3 Visual motion perception in albinotic and pigmented ferrets..........................34
3.1 Animals...................................................................................................34
3.2 Setup ......................................................................................................35
3.3 Procedure...............................................................................................35
3.3.1 Handshaping ...................................................................................36
3.3.2 Discrimination training .....................................................................36
3.3.3 Coherence discrimination ................................................................37
3.4 Stimuli.....................................................................................................38
3.4.1 Training ...........................................................................................38
3.4.2 Coherence detection and threshold.................................................39
3.5 Analysis ..................................................................................................40
3.6 Results....................................................................................................41
3.6.1 Visual discrimination and coherence detection................................41
3.6.2 Coherence threshold .......................................................................42
3.7 Conclusions............................................................................................44
4 Effects of PSS lesions on visual motion perception in ferrets ........................45
4.1 Introduction.............................................................................................45
4.2 Materials and methods ...........................................................................46
4.2.1 Animals............................................................................................46
4.2.2 Stimuli..............................................................................................47
4.2.3 Prelesion training.............................................................................48
4.2.4 Measurements of the horizontal optokinetic reaction.......................49
4.2.5 Surgery............................................................................................50
4.2.6 Postlesion training ...........................................................................52
4.2.7 Analysis ...........................................................................................52
4.3 Results....................................................................................................53
4.3.1 Reconstruction of cortical lesions ....................................................53
4.3.2 Pre- and postlesion visual discrimination performance....................61
II 4.3.3 Horizontal optokinetic reaction.........................................................65
4.4 Conclusion..............................................................................................70
5 Visual acuity and contrast sensitivity of albinotic and pigmented ferrets........71
5.1 Introduction.............................................................................................71
5.1.1 Influence of dot size on coherence detection ..................................71
5.2 Materials and methods ...........................................................................72
5.2.1 Animals............................................................................................72
5.2.2 Setup and stimuli.............................................................................72
5.2.3 Procedure........................................................................................73
5.2.4 Analysis ...........................................................................................74
5.3 Results....................................................................................................74
5.3.1 Visual acuity ....................................................................................74
5.3.2 Contrast sensitivity function.............................................................75
5.4 Conclusion..................................