Reizabhängige Synchronisation im Sehsystem der Katze [Elektronische Ressource] / von Tilmann Kluge

Tilmann Kluge

Informations

• Publié par: goethe_universitat_frankfurt_am_main
• Publié le: 01 janvier 2005
• Nombre de lectures: 28
• Langue: Deutsch
• Poids de l'ouvrage: 2 Mo

Extrait

Aus dem Max-Planck-Institut für Hirnforschung
Reizabhängige Synchronisation im
Sehsystem der Katze
Dissertation
zur Erlangung des Doktorgrades
der Naturwissenschaften
vorgelegt beim Fachbereich Physik
der Johann-Wolfgang-Goethe-Universität
in Frankfurt am Main
von
Tilmann Kluge
aus Hameln
Frankfurt 2004
(DF1)
Vom Fachbereich Physik der Johann-Wolfgang-Goethe-Universität
als Dissertation angenommen.
Dekan: Prof. Dr. Dörner
Gutachter: Prof. Dr. Ronald Tetzlaff
Prof. Dr. Wolf Singer
Datum der Disputation: 04. Juni 2004
TABLE OF CONTENTS
CHAPTER 1: INTRODUCTION .............................................................................................1
CHAPTER 2: NEUROPHYSIOLOGICAL BACKGROUND ......................................................7
2.1.Introduction ...........................................................................................................7
2.2.The Neuron ............................................................................................................8
2.3.The Visual System of the Cat ..............................................................................9
2.4.Binding Problem and Neuronal Synchronization ...........................................14
CHAPTER 3: MATERIALS AND METHODS .........................................................................19
3.1.Preparation 19
3.2.Data Acquisition ...................................................................................................21
3.3.Stimuli ....................................................................................................................22
3.3.1.The Tuning Curve Stimulus ........................................................................23
3.3.2.Random Dot Stimulus with Changing Stimulus Coherence ..................25
3.3.3.The Shape-From-Motion Stimulus .............................................................26
3.4.Indices for Quantification of the Tuning curve ................................................30
3.4.4.Preferred Direction and Direction index ...................................................30
3.4.5.Tuning Width Index .....................................................................................32
3.5.Analysis of Spike Signals 33
3.5.6.Quantification of Firing Rates .....................................................................33
3.5.7.Cross Correlation Analysis ..........................................................................34
3.6. Analysis of the Local Field Potential ................................................................38
3.6.8.Power Spectrum of the LFP .........................................................................39
3.6.9.Spike-Triggered Average .............................................................................40
3.6.10.Spike-Field-Coherence ...............................................................................41
3.7.Statistical Analysis ................................................................................................43
3.7.11.Normal distribution ....................................................................................43
3.7.12.The t-Test ......................................................................................................45
3.7.13.Analysis of Variance (ANOVA) ................................................................46
3.7.14.Fisher‘s Protected Least Significant Difference Test ..............................48
CHAPTER 4: INCOHERENT MOTION IN
AREAS 17 AND PMLS .......................................................................................................49
4.1.Introduction ...........................................................................................................49
4.2.Tuning Behavior of Spatially Incoherent Stimuli ............................................55
4.2.1.Introduction ...................................................................................................55
4.2.2.Results .............................................................................................................56
Area 17 56
Area PMLS ................................................................................................59
4.2.3.Discussion ......................................................................................................61
4.3.Effects of Visual Noise on Firing Rates
i
in Areas 17 and PMLS ................................................................................................66
4.3.4.Introduction ...................................................................................................66
4.3.5.Results .............................................................................................................67
Area 17 .......................................................................................................68
Area PMLS 71
Stimulation in the null direction ............................................................73
4.3.6.Discussion ......................................................................................................74
4.4.Synchrony in Incoherent Stimuli ........................................................................78
4.4.7.Introduction 78
4.4.8.Results 79
Area 17 79
Area PMLS ................................................................................................82
4.4.9.Discussion 86
4.5.Power Spectra of the Local Field Potential .......................................................94
4.5.10.Introduction .................................................................................................94
4.5.11.Results ...........................................................................................................95
Area 17 .......................................................................................................95
Area PMLS ................................................................................................98
4.5.12.Discussion ....................................................................................................101
4.6.Spike Field Coherence ..........................................................................................105
4.6.13.Introduction 105
4.6.14.Results 105
Area 17 .......................................................................................................105
Area PMLS 109
4.6.15. Discussion ...................................................................................................113
4.7.Summarizing Discussion .....................................................................................115
4.8.Conclusions ...........................................................................................................123
CHAPTER 5: ANALYSIS OF SHAPE-FROM-MOTION STIMULI IN AREA PMLS ................125
5.1.Introduction 125
5.2.Results ....................................................................................................................129
5.2.1.Shape-From-Motion Tuning Curve ............................................................129
5.2.2.Processing of Contours in Shape-From-Motion Stimuli .........................133
Effects of static random dot backgrounds on firing rates ..................134
Effects of moving RD backgrounds ......................................................136
Effect of masking .....................................................................................138
Effects of visual noise ..............................................................................140
SFM bar with different directions of dot motion ................................140
5.3.Discussion ..............................................................................................................143
Response strength without background ..............................................143..................144
Effects of moving RD backgrounds ......................................................145
Effects of visual noise 147
Effect of masking 149
SFM bars with different directions of dot motion ...............................150
SFM tuning curve stimulus ....................................................................151
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5.4.Conclusion .............................................................................................................154
CHAPTER 6: OUTLOOK ......................................................................................................155
CHAPTER 7: BIBLIOGRAPHY ..............................................................................................161
CHAPTER 8: LIST OF FIGURES ...........................................................................................175
CHAPTER 9: LIST OF ABBREVIATIONS ...............................................................................177
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ZUSAMMENFASSUNG
Die vorliegende Arbeit soll einen Beitrag zur Erforschung der Verar-
beitungsmechanismen des Gehirns leisten. Die Erregung des komplexen
Systems "Hirn" liefert Antworten, deren Analyse zu einem besseren Ver-
ständnis dieser Informationsverarbeitung führt. Zu diesem Zweck wurde
das Gehirn mit unterschiedlichen visuellen Stimuli angeregt und die hir-
nelektrischen Signale gemessen, die von Nervenzellgruppen (Multiunits)
im visuellen Kortex de