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Table of contents
Content
General Introduction
1.1 The construction of a global percept
1.1.1 Psychophysical rules underlying perceptual binding and information extraction
1.2 Receptive fields along the visual pathway
1.2.1 Simple and complex cells of the primary visual cortex
1.2.2 A columnar organization
1.2.3 A hierarchical processing of information
1.2.4 Questioning the hierarchical model
1.3 Center-surround interactions: physiological definition, spatial scale, connectivity’s origins across species and link with perception
1.3.1 Contrast-dependent spatial summation of the Receptive field
1.3.2 Thalamo-cortical contribution of macaque LGN inputs to V1 center-surround modulations …..
1.3.3 Aggregate receptive field and intra V1 lateral connectivity’s contribution to macaque V1 near and far surround modulation
1.3.4 Lateral connectivity, collinear facilitation and link with perception
1.3.5 Differences and similarities between cat and monkey’s lateral connectivity: implication for perception
1.4 Connectivity types and canonical circuits involved in lateral processing
1.4.1 Thalamo-cortical feedforward connectivity’s contribution to V1 center-surround modulations 53
1.4.2 Feedback connectivity
1.4.3 A laminar dependency?
1.4.4 Local recurrent connectivity
1.4.5 Horizontal connectivity
1.5 Role of V1 lateral connectivity in low level perception
Part I – Lateral connectivity and the propagation of network belief
I-1. Background
I-1.1 Anatomy
I-1.1.1 Iso-orientation bias in excitatory horizontal connectivity?
I-1.1.2 Spatial spread of horizontal connections
I-1.1.3 Iso-orientation binding across the retinotopic map
I-1.1.4 Excitatory versus inhibitory horizontal connectivity
I-1.2 Functional role
I-1.2.1 Role of feature geometry in response modulation
I-1.2.2 Overall center-surround contextual modulations
I-1.2.3 The depolarizing field hypothesis
I-1.2.4 Intracellular recordings: spatio-temporal subthreshold characterisation of the receptive field silent surround
I-2. Working Hypothesis
I-2.1 Spread of horizontal activity in V1
I-2.1.1 Lateral and feedforward activity interact in a spatio-temporal coherent way to shape the overall propagation of cortical activity
I-2.1.2 Stimulus-induced cooperativity is necessary for the anisotropic spread of lateral activity ……
I-2.1.3 The existence of a synaptic dynamic association field favouring the integration of iso-aligned elements composing a centripetal flow
I-2.2 Exploring in depth the dynamic association field and its implication in the propagation of a prediction travelling through the V1 network
I-2.3 Filling-in and predictive responses
I-3. Visual stimuli design
I-3.1 Geometric design of the stimulation and definition of a common cellulo-centric referential
I-3.2 General Spatio-Temporal design of apparent motion (AM) sequences
I-3.3 Contrast conditions
I-3.4 Probing filling-in or predictive responses
I-3.5 Probing the implication of horizontal connectivity
I-3.6 Manipulating the spatial coherence of the flows
I-3.7 Manipulating the spatial and temporal coherence of the flows
I-3.8 Probing the existence of local versus global motion flow detectors
I-4. Material and methods
I-4.1 Animal breeding
I-4.2 Surgical procedure and animal preparation
I-4.3 Intracellular recordings
I-4.4 On-line characterization of receptive fields
I-4.5 Histology
I-4.6 – Part I Assessing cells responses linear prediction
I-5. Results
I-5.1 Assessing visual response significance
I-5.2 Input summation during centripetal apparent motion
I-5.3 Spatio-temporal coherence is necessary for binding lateral and horizontal waves
I-5.4 Apparent motion speed needs to match the cortical horizontal propagation speed
I-5.5 Predictive/filling-in responses
I-5.6 Reversal of V1 neuron axial sensitivity as a function of the retinal flow speed
I-6. Discussion
I-6.1. General context of the findings
I-6.2. Summary of the main findings
I-6.3 Gain control during centripetal apparent motion
I-6.4 Non–linear Center–Surround spatio–temporal integration during apparent motion: the roles of spatial synergy and temporal coherence and their implication in the predictive coding hypothe
I-6.5 Experimental evidence of prediction influence throughout the cortical hierarchy
I-6.6 Human experimental evidence of predictive influence in coherent motion integration
I-6.7 Filling-in as a prediction
I-6.8 V1’s latency advance as a neuronal correlate of psychophysical speed overestimation of co-aligned elements apparent motion
I-6.9 Functional shift of the synaptic integration field anisotropy as a function of the speed of the global motion flow
I-6.10 Reconfiguration of retinal flow integration by lateral connectivity during oculomotor exploration
I-6.11 Binding in-phase versus rolling wave
I-6.12 Future work and bottleneck
Part II – Lateral connectivity and hallucinatory-like states in V1
II-1. Background
II-1.1 On the origins of Geometric hallucinations in the brain
II-1.2 Beyond Mackay’s after-effect: sequential and simultaneous contrast adaptation and spatial opponency
II-1.3 Theoretical models of selection and stabilisation of spatio-temporal stable states intrinsic to V1’s functional architecture
II-2. Working Hypothesis
II-2.1 Geometric pattern formation results from a repulsive shift in orientation within and between hypercolumns: link between experimental data and theoretical models
II-2.1.1 Neural Stripes of activity in V1 results in a smooth spatial gradient of orientation preference shifts
II-2.1.2 Psychophysical evidence of repulsive shift in orientation
II-2.1.3 Electrophysiological evidence of repulsive shift in orientation
II-2.1.4 Lateral connectivity as a self-organizing engine for the spatial propagation of fast repulsive orientation shift adaptation
II-2.1.5 Model of coupled hypercolumns under global repulsive shift
II-2.1.6 Formation of static vs dynamic hallucinatory planforms
II-2.2 Geometric physical inducers constrain orientation domains exploration: towards a directly inducible and temporally stable percept
II-2.2.1 Experimental evidence of smooth spontaneous orientation transition between neighbouring hypercolumns
II-2.2.2 Biasing ongoing activity’s orientation exploration by the physical presentation of a geometric planform inducer combined with a perturbation
II-2.2.3 Oscillatory activity accompanies dynamic, propagating percepts: implications of 1/f α filtered noise in pattern formation and propagation
II-2.3 The cat as a model of geometric hallucinations in the brain
II-3. Visual stimuli design
II-3.1 Probing the geometric nature of hallucinatory-like propagating waves of activity and maximizing their detectability at the single cell level
II-3.2 Probing the need of a synergistic interaction between geometric inducer and 1/fα noise in the emergence of hallucinatory-like waves of activity
II-3.3 Geometry’s position and luminance equalization across conditions
II-3.4 Temporal display of the stimuli
II-3.5 Generation of 1/fα spatiotemporally filtered noise
II-3.5.1 Spatial filtering of the noise
II-3.5.2 Temporal filtering of the noise
II-4. Results
II-4.1 Detecting oscillatory activity
II-4.2 Stimulus-locked analysis
II-4.3 Sustained nature of the oscillations and autocorrelation measures
II-4.4 Comparison between the Power spectral content of stimulus locked and stimulus-induced response components
II-4.4.1 Average cross spectrum between each pair of trials and dephasing
II-4.4.2 Signal, Noise, total signal power and Signal to Noise Ratio evaluation
II-4.5 Population analysis
II-4.5.1 Power spectral content of the trials
II-4.5.2 Dephasing of the cross spectrum average and power spectral content of stimulus-locked oscillations
II-4.5.3 Signal, noise, and total signal power spectral estimation
II-4.5.4 Signal to noise ratio and information rate
II-4.6 Supplementary figures
II-5. Discussion
II-5.1. From subjectivity to an Archetype
II-5.2. Lateral diffusion of repulsive shift in orientation between neighbouring hypercolumns as a potential mechanism of neural stripe formation on V1
II-5.3. Multiscale evidence of repulsive shift in orientation as the substrate of our model
II-5.4. Potential implications and parametrization
II-5.5. Experimental framework: subthreshold detectability of hallucinatory-like propagating waves of activity by intracellular recordings in the cat V1
II-5.6. Neural stripe formation and propagation refractory period as a signature of an intrinsic clock of the primary visual cortex
II-5.7. Future work and potential implications
Bibliography
