Imaging development and plasticity in the mouse visual system [Elektronische Ressource] / vorgelegt von Sonja Hofer

Sonja Hofer

Sujets

• Biologie

Informations

• Publié par: ludwig-maximilians-universitat_munchen
• Publié le: 01 janvier 2006
• Nombre de lectures: 75
• Langue: English
• Poids de l'ouvrage: 7 Mo

Extrait

Imaging development and plasticity
in the mouse visual system

Dissertation
zur Erlangung des Grades eines Doktors
der Naturwissenschaften

der Fakultät für Biologie
der Ludwig-Maximilians-Universität München






vorgelegt
von
Sonja Hofer
München, Mai 2006

















Erstgutachter: PD Dr. Mark Hübener
Zweitgutachter: Prof. Dr. Benedikt Grothe

Tag der mündlichen Prüfung: 22.06.2006 Ehrenwörtliche Versicherung:
Ich versichere hiermit ehrenwörtlich, dass ich die Dissertation mit dem Titel „Imaging
development and plasticity in the mouse visual system” selbständig und ohne unerlaubte
Beihilfe angefertigt habe. Ich habe mich dabei keiner anderen als der von mir ausdrücklich
bezeichneten Hilfen und Quellen bedient.

Erklärung:
Hiermit erkläre ich, dass ich mich nicht anderweitig einer Doktorprüfung ohne Erfolg
unterzogen habe. Die Dissertation wurde in ihrer jetzigen oder ähnlichen Form bei keiner
anderen Hochschule eingereicht und hat noch keinen sonstigen Prüfungszwecken gedient.

München, den 23.05.2006


Sonja Hofer

Acknowledgements
First and foremost I wish to thank PD Dr. Mark Hübener for being such a great, caring and
helpful supervisor. Besides creating a wonderful working atmosphere, he, even in the most
stressful situations, always took the time to listen and help, to give advice and to thoroughly
discuss scientific and personal issues. I continuously felt warmly and cheerfully guided and at
the same time enjoyed the freedom to develop my own ideas and work independently.
I am also very grateful to Prof. Dr. Tobias Bonhoeffer for giving me the opportunity to
accomplish my PhD thesis in his excellent laboratory. I always felt assured of his generous
support and warm encouragement. I was time and time again impressed by his amazing skill to
negotiate his busy schedule, as he always found the time for valuable counsel, advice and
discussion.
I would like to thank the members of my thesis committee, Prof. Dr. Benedikt Grothe, Prof.
Dr. Martin Korte and Prof. Dr. Axel Borst for fruitful discussions and helpful suggestions.
I am thankful to Volker Staiger who, besides relieving me of the hated task of solution
making, is always extremely competent and very patient towards any kind of question or
problem. Thanks also to Max Sperling for his help with programming and general computer
problems.
Special thanks to the ‘in vivo’ gang for shared sorrows, encouraging conversations, wonderful
tap dances and highly enriched Monday afternoons, and to the girls from the ‘Blocksberg’ for
always having an open ear and a cheery comment, it is a pleasure to share room with you.
I really enjoyed the good spirits in the Bonhoeffer department. Thanks to everybody for the
very nice time, enjoyable lunches and coffee breaks, relaxing sports activities and especially all
the tasty cakes, which often saved my day.
My deep gratitude goes to my family for making all this possible, always standing behind me
and spoiling me in the kindest way.
All my thanks and love to Thomas Mrsic-Flögel for simply being everything I could possibly
ever ask for.
Table of contents
Table of contents....................................................................................................1
Summary.................................................................................................................3
Abbreviations .........................................................................................................5
1. Introduction ......................................................................................................6
1.1. The mouse visual system .......................................................................................................7
1.2. Visual system development ...................................................................................................9
1.3. Ocular dominance plasticity in mouse visual cortex........................................................13
1.4. Summary of aims ..................................................................................................................23
2. Altered map of visual space in the superior colliculus of mice lacking
early retinal waves............................................................................................25
2.1. Abstract ..................................................................................................................................25
2.2. Introduction...........................................................................................................................26
2.3. Material and Methods...........................................................................................................27
2.4. Results.....................................................................................................................................29
2.4.1. Imaging intrinsic signals in the SC..............................................................................29
2.4.2. Stimulus mapping reveals broader activations in the SC of ß2-/- mice................30
2.4.3. Mapping functional retinotopy in the SC ..................................................................32
2.4.4. Gross retinotopic organization is altered in the SC of ß2-/- mice ........................34
2.4.5. Size, elongation and orientation of response patches vary systematically
along the SC ...................................................................................................................36
2.5. Discussion..............................................................................................................................39
2.5.1. Mapping intrinsic signals in the SC.............................................................................39
2.5.2. Local topography is functionally less refined in ß2-/- mice ...................................39
2.5.3. Coarse retinotopy is altered in ß2-/- mice.................................................................40
2.5.4. General implications for activity-dependent map formation..................................42
3. Prior experience enhances plasticity in adult visual cortex ...........................43
3.1. Abstract ..................................................................................................................................43
3.2. Introduction...........................................................................................................................44
1
Table of contents

3.3. Material and Methods.......................................................................................................... 45
3.4. Results.................................................................................................................................... 48
3.4.1. Imaging of mouse binocular visual cortex................................................................ 48
3.4.2. Determining OD shifts with intrinsic optical imaging............................................ 50
3.4.3. Critical period MD facilitates OD plasticity in adults ............................................. 51
3.4.4. Adult MD experience facilitates subsequent OD plasticity.................................... 53
3.4.5. The facilitatory effect of prior MD is eye specific................................................... 57
3.5. Discussion ............................................................................................................................. 59
3.5.1. Intrinsic signal imaging of OD plasticity................................................................... 59
3.5.2. Strength of eye representation after juvenile and adult MD .................................. 60
3.5.3. Facilitation of adult OD plasticity by prior MD experience 61
3.5.4. Specific trace in the visual cortex ............................................................................... 62
3.5.5. General implications..................................................................................................... 63
4. Monocular deprivation induces bidirectional scaling of eye-specific
responses in primary visual cortex...................................................................65
4.1. Abstract.................................................................................................................................. 65
4.2. Introduction.......................................................................................................................... 66
4.3. Material and Methods.......................................................................................................... 68
4.4. Results.................................................................................................................................... 71
4.4.1. Mapping ocular dominance with in vivo calcium imaging ..................................... 71
4.4.2. Bidirectional changes of eye-specific responses induced by MD.......................... 73
4.4.3. Orientation selectivity in mouse visual cortex after MD ..................