INS/INT Keynote Seminar – Danielle Bassett (Philadelphia, USA)

From Friday 26th January 2018 at 14:30
To Friday 26th January 2018 at 16:00

Location : INS seminar room (5th floor) Faculty of medecine, La timone Marseille

"The Network Architecture of Human Thought"

Human thought is predicated on a complex architecture of interconnections that enable information transmission between distinct areas ofthe brain. Yet gaining a fundamental understanding of this architecture has remained challenging, largely due to insufficiencies in traditional imaging techniques and analytical tools. In concerted efforts to address these challenges, neuroscientists have begun to combine recent breakthroughs in non-invasive brain imaging techniques with the conceptual notions and mathematical tools of network science – leading to the emerging field ofnetwork neuroscience. This talk will highlight early successes in this field leading to fundamental understanding of healthy human thought, its development over childhood, and its alteration in psychiatric disease and neurological disorders. The talk will close by commenting on current frontiers and future potential in health care, business, and education sectors.

For any question, feel free to contact:
Benjamin Morillon (bnmorillon@gmail.com) or Adam Williamson (adam.WILLIAMSON@univ-amu.fr)

 

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INS Topical Seminar – Davide Ragozzino (Rome, Italy)

From Thursday 30th November 2017 at 14:00
To Thursday 30th November 2017 at 15:30

Location : INS seminar room (5th floor) Faculty of medecine, La timone Marseille

"Microglia shape presynaptic properties at developing glutamatergic synapses"

Deficient neuron-microglia signaling during brain development is associated with abnormal synaptic maturation. However, the precise impact of deficient microglia function on synaptic maturation and the mechanisms involved remain poorly defined.
Here we report that mice defective in neuron-to-microglia signaling via the fractalkine receptor (Cx3cr1 KO) show reduced microglial branching and altered motility and develop widespread deficits in glutamatergic neurotransmission. We characterized the functional properties of CA3-CA1 synapses in hippocampal slices from these mice and found that they display altered glutamatergic release probability, maintaining immature properties also at late developmental stages. In particular, CA1 synapses of Cx3cr1 KO show: (i) immature AMPA/NMDA ratio across developmental time displaying a normal NMDA component and a defective AMPA component of EPSC; (ii) defective functional connectivity, as demonstrated by reduced current amplitudes in the input/output curve; and (iii) greater facilitation in the paired pulse ratio (PPR), suggesting decreased release probability. In addition, minimal stimulation experiment revealed that excitatory synapses have normal potency, but an increased number of failures, confirming a deficit in presynaptic release. When the deficit in release probability was corrected by performing experiments in high Ca2+/Mg2+, excitatory synapses showed normal synaptic multiplicity and AMPA/NMDA ratio.
These results establish that neuron-microglia interactions profoundly influence the functional maturation of excitatory presynaptic synapse function.

For any question, feel free to contact:
Benjamin Morillon (bnmorillon@gmail.com) or Adam Williamson (adam.WILLIAMSON@univ-amu.fr)

 

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INS Keynote Seminar – Lyon Research Team (France)

From Tuesday 28th November 2017 at 14:00
To Tuesday 28th November 2017 at 15:30

Location : INS seminar room (5th floor) Faculty of medecine, La timone Marseille

"Dynamics of Embodied Cognition in Humans and Robots"

Jocelyne Ventre-Dominey, Carol Madden-Lombardi and Peter Dominey

Human and Robot Cognitive Systems- Inserm U1208- Bron, France

The goal of our research is to understand the neural basis and organization of the sensori-motor systems responsible for visuo-spatial orientation and spatial representation in interaction with language. Over the past few decades, embodied cognition theory has suggested a tight coupling between sensori-motor functions and language, as understanding verbal stimuli (words, sentences, narrative) triggers sensori-motor experiential traces grounded in neural networks. Beyond language, the comprehension of perceived events in the world around us relies on the internal simulation of our own previous experiences in a multimodal framework. Such an embodied theory of meaning implies interacting cognitive systems including tight coupling between visuo-spatial representations and language functions. While these two functions have been well studied in separate fields, the mechanisms and neural substrates of their coupling in higher-order cognitive operations remain to be characterized.

By combining neuroscience and psychology expertise in both sensori-motor and language domains, integrated with computational neuroscience and neuro-robotics, our team project addresses several themes of this general topic: 1) the neural mechanisms and the organization underlying sensori-motor interactions involved in both space representation and language comprehension, 2) the organization of the spatio-temporal structure of embodied event simulations serving narrative comprehension and 3) the development of neuro-computational models of these dynamic cognitive functions for model-based analysis of brain dynamics, and for developing cognitive functions in humanoid robots. Finally these research findings will provide a basis for further translational applications of these cognitive functions in aging, reeducation, and psychiatry (autism).

For any question, feel free to contact:
Benjamin Morillon (bnmorillon@gmail.com) or Adam Williamson (adam.WILLIAMSON@univ-amu.fr)

 

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INS/INT Keynote Seminar – Stefano Panzeri (Rovereto, Italy)

From Thursday 9th November 2017 at 14:00
To Thursday 9th November 2017 at 15:30

Location : INS seminar room (5th floor) Faculty of medecine, La timone Marseille

"The relationship between cross-cell coupling and the timescales of population coding across cortex"

The cortex needs to represents information across a wide range of timescales, from the millisecond-scale required to encode rapidly fluctuating sensory stimuli, to the maintenance of information over seconds that is required to implement certain behavioral choices. Do such diverse timescales result mostly from features intrinsic to individual neurons or from correlated activity in neuronal populations ? Here we report that population codes can be essential to achieve long coding timescales, and that the properties and time scales of population codes differ between sensory and association cortices. We compared coding for sensory stimuli and behavioral choices in auditory cortex (AC) and posterior parietal cortex (PPC) as mice performed a sound-localization task. Auditory stimulus information was strong in AC but weak in PPC, and both regions contained choice information. Although AC and PPC coded information by tiling in time neurons that were transiently informative, the areas had major differences in functional coupling between neurons, measured as activity correlations that could not be explained by task events. Coupling among PPC neurons was strong and extended over long time lags, whereas coupling among AC neurons was weak and short-lived. Stronger coupling in PPC led to a population code with long timescales and a representation of choice that remained consistent for approximately one second. In contrast, AC had a code with rapid fluctuations in stimulus and choice information over hundreds of milliseconds. Our results reveal that population codes differ across cortex and that cross-cell coupling affects the timescale of information coding.
This is joint work with Carolyne Runyan at Chris Harvey at Harvard Medical School and with Eugenio Piasini at IIT.

For any question, feel free to contact:
Benjamin Morillon (bnmorillon@gmail.com) or Adam Williamson (adam.WILLIAMSON@univ-amu.fr)

 

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INS Topical Seminar – Beate Diehl (London, UK)

From Thursday 2nd November 2017 at 16:00
To Thursday 2nd November 2017 at 18:00

Location : INS seminar room (5th floor) Faculty of medecine, La timone Marseille

 

"Direct Electrical Cortical Stimulation: Disrupting the epileptic brain - What can we learn about brain function"

Direct Electrical Cortical Stimulation is used to map cortical functions during awake surgery and chronic intracranial EEG (iEEG) recordings for presurgical evaluation in epilepsy. Although there is lack of standardization across centers, it is considered the gold standard to for mapping of cortical function and to define eloquent cortex. It allows a unique opportunity to gain access to the epileptic brain. In this talk I will show cortical stimulation mapping using grids mainly, illustrating effects and side effects of stimulation mapping and opportunities to define brain function also in less accessible regions such as the medial frontal lobe.

For any question, feel free to contact:
Benjamin Morillon (bnmorillon@gmail.com) or Adam Williamson (adam.WILLIAMSON@univ-amu.fr)

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INS Topical Seminar – Andrea Protzner (Calgary, Canada)

From Thursday 12th October 2017 at 16:00
To Thursday 12th October 2017 at 18:00

Location : INS seminar room (5th floor) Faculty of medecine, La timone Marseille

 

"How do age-related changes in brain signal variability relate to individual differences in functional capacity and performance?"

Recent empirical work has demonstrated that variability in network dynamics differs between younger and older adults. With increasing age, brain signal variability decreases at coarse temporal scales and increases at fine temporal scales, suggesting a shift from global toward more local neural processing. I will discuss how these age-related changes relate to task performance (e.g., visual word recognition in healthy adults), and how they relate to the capacity for normalization in brain disease (e.g., depression).

For any question, feel free to contact:
Benjamin Morillon (bnmorillon@gmail.com) or Adam Williamson (adam.WILLIAMSON@univ-amu.fr)

 

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(Français) 20èmes journées Françaises de l’Epilepsie (JFE)

From Monday 9th October 2017 at 11:00
To Thursday 12th October 2017 at 16:00

Location : Palais du Pharo 58, Boulevard Charles Livon Marseille

 

JFE

 

 

This page is only available in French

 

 

 

 

 

 

Enregistrer



INS Topical Seminar – David Howard (Newcastle, UK)

From Thursday 5th October 2017 at 16:00
To Thursday 5th October 2017 at 18:00

Location : INS seminar room (5th floor) Faculty of medecine, La timone Marseille

 

"Treatment of word retrieval: contrasting results from 2 RCTs"

This talk will describe the results of two partly parallel randomised controlled crossover treatment trials. Both contrasted a treatment emphasising semantics with a treatment concentrating on phonological information. One trial was with people with stroke aphasia and the second with normal children with word finding difficulties. Both trials found improvement only with treated items, but they differed in whether the results could be predicted from the background tests probing related cognitive functions.

For any question, feel free to contact:
Benjamin Morillon (bnmorillon@gmail.com) or Adam Williamson (adam.WILLIAMSON@univ-amu.fr)

 

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INS Topical Seminar – Jean-Rémi King (New York)

From Monday 28th August 2017 at 10:30
To Monday 28th August 2017 at 12:00

Location : INS new seminar room on 5th floor Faculty of medecine, La timone Marseille

 

"Identifying the neural architecture of human cognition"

What computations are specific to human cognition? Are they supported by a particular neural architecture? How might such an architecture supplement the design of machine learning algorithms? Here, I will argue that the recent developments in 1) machine learning and 2) temporally-resolved neuroimaging offer a new opportunity to address these foundational issues. In particular, I will show how we can track the unfolding of complex cognitive processes, such as perceptual decision making and speech comprehension, and identify what representations the human brain encodes, selects, and maintains at each instant in time. The present studies show how we can isolate and track a multitude of processing stages reminiscent of deep neural networks. Finally, I outline a few promising research directions to investigate parallel, serial, and recursive computations in syntactic processing and conceptual composition. I argue that the present research program will pave the way to integrate the disciplines of biological and artificial cognition.

For any question, feel free to contact:
Demian Battaglia (demian.battaglia@univ-amu.fr) or Benjamin Morillon (bnmorillon@gmail.com)

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INS Topical Seminar – Christine Métin (Paris)

From Thursday 13th July 2017 at 14:00
To Thursday 13th July 2017 at 15:30

Location : INS new seminar room on 5th floor Faculty of medecine, La timone Marseille

"Cellular mechanisms regulating the cortical distribution of GABAergic interneurons"

The p21 activated kinases (PAKs) are activated by Rac1 and Cdc42 and regulate the dynamics and contractility of the acto-myosin cytoskeleton, and the turnover of adhesive contacts. Mutations in one isoform, PAK3, are responsible in humans of X-linked non-syndromic intellectual disability. Pak3 is expressed in tangentially migrating interneurons in the developing cortex. By overexpressing mutants that mimic human mutations (kinase dead or defective for GTPase binding) or a constitutively active mutant, we have analyzed the influence of PAK3 activity on the morphology, dynamic behavior and on the trajectories of migrating interneurons in the developing cortex.

Christine Métin, DR2 INSERM, co-leads with P. Gaspar the team ”Developmental mechanisms of brain disorders” at Institut du Fer à Moulin (IFM) in Paris. With her group, C. Métin analyzes the cellular mechanisms that regulate the long distance migration of cortical interneurons from the basal forebrain to the developing cortex. She uses in vivo models to study how the migratory defects of interneurons alter their final distribution in the cortical target. In collaboration with the team of C. Bernard, she studies the consequences of interneuron migratory defects on the activity of cortical networks.

For any question, feel free to contact:
Demian Battaglia (demian.battaglia@univ-amu.fr) or Benjamin Morillon (bnmorillon@gmail.com)



1st AM*IDEX CompNeuro Days

From Wednesday 12th July 2017 at 9:00
To Thursday 13th July 2017 at 17:00

Location : INMED, Luminy

 
The aim of this workshop is to gather researchers active in the field of general computational neuroscience to illustrate the diversity of its approaches and the richness of cooperation between theorists and experimentalists
and all this in an informal atmosphere favourable to discussions. 

PhD students are warmly welcome and will be given the opportunity to present their research (not necessarily computational, on the contrary!) in Blitz oral presentations (ca. 5 min) and/or poster.

*** The registration is open and compulsory (deadline July 2nd), but free ***

In addition the students willing to present their result should send an email with a short title and abstract, name of the supervisor to the organisers:
Alessandro Torcini (torcini@gmail.com), David Angulo Garcia (david.angulo-garcia@univ-amu.fr), Demian Battaglia (demian.battaglia@univ-amu.fr)

They will then be informed of the type of presentation assigned to them (Blitz oral or poster). There are only limited slots available for oral, so priority will be given to thematic diversity.

List of speakers:
• Nicolas Brunel (Chicago, USA),
• Frederic Chavane (Marseille, France)
• Daniel Durstewitz ( Mannheim, Germany)
• Boris Gutkin (Paris, France)
• Vincent Hakim (Paris, France)
• David Hansel (Paris, France)
• Viktor Jirsa (Marseille, France)
• Anna Levina (Klosterneuburg, Austria)
• Nicolas Mallet (Bordeaux, France)
• Arnaud Malvache (Marseille, France)
• Gianluigi Mongillo (Paris, France)
• Alfonso Renart (Lisbon, Portugal)
• Petra Ritter (Berlin, Germay)


Sponsors:

A*Midex, INMED, Institut de Neurosciences des Systèmes, Institut de Neurosciences de La Timone, EPINEXT, PhD Program in Integrative and Clinical Neurosciences, Mediterranean Neuroscience Society, Marie Curie Actions, Società Italiana Caos e Complessità


INS Epinext Seminar – Randy McIntosh (Toronto)

From Tuesday 11th July 2017 at 14:00
To Tuesday 11th July 2017 at 15:30

"Why Dynamics are Vital for Brain Health"

Brain networks have a rich functional repertoire. The architecture of the brain is such that communication between regions shows differing time delays dependent partly on distance. These time delays, considered in the context of the spatial distribution of regions, establish a space-time structure that characterizes the potential network dynamics that can be supported by a given brain. We have shown that the this space-time structure sculpts the dynamics in a principled manner during maturation and senescence. In childhood, the dynamics change most at slower timescales favouring distributed networks. In healthy ageing there appears to be a shift in dominant timescales so as to bias the dynamics to local networks. Clinical studies suggest that if such a shift in preferred timescales does not happen cognitive dysfunction ensues. These studies reinforce the need to carefully consider brain dynamics as a more sophisticated index of brain health and dysfunction.

For any question, feel free to contact:
Demian Battaglia (demian.battaglia@univ-amu.fr) or Benjamin Morillon (bnmorillon@gmail.com)



INS Keynote Seminar – Joachim Gross (Glasgow)

From Friday 30th June 2017 at 14:00
To Friday 30th June 2017 at 15:30

Location : INS new seminar room on 5th floor Faculty of medecine, La timone Marseille

"Cycles of coordination and communication in the human brain"

Invasive and noninvasive studies in humans under physiological and pathological conditions converged on the suggestion that brain oscillations are related to cognitive processes such as sensory representations, attentional selection, and dynamical routing/gating of information. I will present recent studies that aim to further our understanding of the computational role of brain oscillations in three different areas: First, to what extent are brain oscillations regional specific and can account for computational specialisation of individual brain areas. Second, are there preferred rhythms that link perception and action and how are they expressed in behaviour. Third, what is the evidence that oscillations play a causal role in perception and action.

For any question, feel free to contact:
Demian Battaglia (demian.battaglia@univ-amu.fr) or Benjamin Morillon (bnmorillon@gmail.com)



INS Topical Seminar – Francesco Cardinale (Italy)

From Friday 23rd June 2017 at 14:00
To Sunday 23rd April 2017 at 15:30

Location : Salle de réunion du service de neurochirurgie (5eme étage, Hôpital Timone Adultes) La Timone Hospital Marseille

"Image guidance to plan SEEG strategy and trajectories"

The processing of neuro-images can be helpful in the field of epilepsy surgery. At “Claudio Munari” Center, Milan, we have developed two original workflows to assist both the planning and the robotic implantation of SEEG electrodes. SUPR-FLAIR analysis can lead to lesion detection and epilepsy network visualization in MRI-negative patients. The other image processing pipeline is aimed at planning safe and accurate SEEG trajectories. Key points and clinical results will be presented.

For any question, feel free to contact:
Demian Battaglia (demian.battaglia@univ-amu.fr) or Benjamin Morillon (bnmorillon@gmail.com)



INS Keynote Seminar – Charlotte Jacquemot (Paris)

From Thursday 8th June 2017 at 14:00
To Thursday 8th June 2017 at 15:30

Location : INS new seminar room on 5th floor Faculty of medecine, La timone Marseille

"Translational research in psycholinguistic: how basic research informs clinical research and vice versa"

Basic and applied research are traditionally conceived as fundamentally different. Applied research is used to answer a specific question that has a direct application, for instance in the medical field; on the contrary, basic research is motivated purely by a desire to expand theoretical knowledge. In my talk, I will argue that tight interactions between basic and applied research – that is translational research- can be fruitful, and show how basic research can inform clinical research and vice versa. I will focus on language processing and its impairments in neurological patients (stroke and neurodegenerative patients) and present two new tools issued from translational research that can be used to improve patients’ care.

For any question, feel free to contact:
Demian Battaglia (demian.battaglia@univ-amu.fr) or Benjamin Morillon (bnmorillon@gmail.com)



INS Topical Seminar – Adrian Ponce Alvarez (Barcelona)

From Thursday 18th May 2017 at 14:00
To Thursday 18th May 2017 at 15:30

Location : INS new seminar room on 5th floor Faculty of medecine, La timone Marseille

"Reduced large-scale models of spontaneous and task brain activity"

Spatial patterns of coherent activity across different brain regions have been identified during the resting-state fluctuations of the brain. The question of how such resting-state functional connectivity (FC) emerges from the brain’s anatomical connections has motivated several experimental and computational studies to understand structure/function relationships. Moreover, it has been shown that resting-state activity is not stationary but shows complex slow temporal dynamics, reflecting the transient formation and dissolution of multiple sub-networks. Theoretical models allow us to investigate explicitly how the interplay between neural dynamics and underlying anatomical connectivity give rise to spatiotemporally organized activity. Using reduced large-scale models, which are mathematical approximations of more biologically plausible models, and analyses of fMRI activity I will show how simple dynamics embedded in the human cerebral connectome can explain i) the emergence of FC, ii) the formation of transient sub-networks, iii) the building up of state-dependent effective connectivity under task conditions, and, finally, iv) I will discuss the models’ functional implications in terms of the information capacity of brain networks and the transmission of stimulus-related information.

For any question, feel free to contact:
Demian Battaglia (demian.battaglia@univ-amu.fr) or Benjamin Morillon (bnmorillon@gmail.com)



The Virtual Brain Node 5 | 2-day Training Workshop in Marseille, 15th-16th May 2017

From Monday 15th May 2017 at 08:30
To Tuesday 16th May 2017 at 18:00

Location : Pedagogical Building (the yellow one), Room 202 Faculty of Medicine at La Timone, 27 Boulevard Jean Moulin Marseille, France

We would like to invite interested students and researchers to the upcoming The Virtual Brain Node 5 workshop held at Faculty of Medicine (yellow building) in Marseille, on 15th - 16th May 2017.

The workshop is dedicated to a theoretical and hands-on understanding of large-scale brain network modeling using the open source neuroinformatics platform The Virtual Brain (TVB). For the first time this workshop will be held over 2 days and will go more in depth regarding the hands-on modeling sessions along explicit use cases from resting state studies and clinical applications to epilepsy and stroke. Also for the first time we will offer in-depth training of fitting virtual brain models to human imaging data. 
 
The Virtual Brain simulation environment enables the biologically realistic modeling of network dynamics using connectome-based approaches across different brain scales. Personalized brain network models can be derived from an individual’s MRI data. Configurable brain network models generate macroscopic neuroimaging signals including functional MRI, intracranial and stereotactic EEG, surface EEG and MEG for single subjects. TVB researchers from different backgrounds can benefit from an integrative software platform including a supporting framework for data management (generation, organization, storage, integration and sharing) and a simulation core written in Python. 

Workshop format: lectures and hands-on tutorials. Participants are encouraged to bring their own data to work on.

Workshop program overview:


- Theoretical background of large scale brain network modeling
- Architecture of The Virtual Brain (TVB)
- Interacting with TVB using GUI and Python interface
- Preprocessing neuroimaging data, or how to obtain a TVB dataset
- Fitting the brain model parameters to the functional data
- Modeling resting state network dynamics in fMRI
- Modeling stroke and recovery
- Modeling epilepsy and surgical interventions
- Modifying TVB code and implementing new features
- Bring your own data hands-on sessions: preprocessing and simulations

Further information and the registration form can be found HERE.

You can find the detailed program and other tips on the official event page.


Registration will be closed on April 20th.


For any questions please contact Viktor Sip (viktor.sip@univ-amu.fr).

Powered by:

TVB_logo            Epinext_logo



INS Keynote Seminar – Christian Jutten (Grenoble)

From Thursday 27th April 2017 at 14:00
To Thursday 27th April 2017 at 15:30

Location : INS new seminar room on 5th floor Faculty of medecine, La timone Marseille

"Source Separation: Principles and Applications on Biomedical Signals"

In the first part of the talk, I will present simple and comprehensive principles of source separation, as well as some results including independent component analysis, and methods based on second order statistics and on sparsity. The second part will illustrate, and sometimes extend methods presented in the first part, on various applications in biomedical signals, especially MEG, EEG and ECG.

Keywords: source separation, independent component analysis, joint diagonalisation, sparse sources, biomedical applications

For any question, feel free to contact:
Demian Battaglia (demian.battaglia@univ-amu.fr) or Benjamin Morillon (bnmorillon@gmail.com)



INS Topical Seminar – Adrien Meguerditchian (LPC, Marseille)

From Thursday 6th April 2017 at 14:00
To Thursday 6th April 2017 at 15:30

Location : New INS Seminar Room, La Timone, Faculty of Medicine, 5th floor, red wing Marseille

 

"On the gestural origins of language: Communication in primates & hemispheric specialization of the brain."

Given the phylogenetical proximity between human and nonhuman primates, research on the communicative, motor and cognitive systems of our primate cousins could help us determining the prerequisites of some language properties inherited from our common ancestor. Whereas some researchers have suggested that language resulted from the evolution of the vocal system, this theory is now challenged by a growing number of authors supporting the “gestural origins” view. Such an alternative theory underlies the fundamental role of gestural communication in the first phylogenetic roots of language.

Such a gestural theory finds support in the considerable evidence of tight links between language organization in humans and gestures including co-speech gestures, sign language in deaf people, and preverbal pointing gestures in infants. Moreover, research has reported potential continuities between the communicative gestural system in nonhuman primates, its latern of the band sel expe fundamentalproperties of language, such as intentionality, learning flexibility, referentitalproperties and left-hemispheric specialization of the brain. In the present communication, I will review our previous and on-going works on the gestural and vocal behaviors in nonhuman primates, latern oty as well as recent findings in anatomical brain imaging in chimpanzees and baboons. I will try to demonstrate that these data in ethology, comparative psychology and neurosciences speak not only for a specific significance of communicative gestures in the course of the language evolution and its hemispheric brain specialization but also for the "bimodal" origin of language with the progressive integration of the oro-facial and vocal control into the gestural intentional system.

 

For any question, feel free to contact:
Demian Battaglia (demian.battaglia@univ-amu.fr) or Benjamin Morillon (bnmorillon@gmail.com)

 



INS/Epinext Topical Seminar – Marta Favali (Paris)

From Friday 17th March 2017 at 11:00
To Friday 17th March 2017 at 12:30

Location : New INS Seminar Room, La Timone, Faculty of Medicine, 5th floor (red wing), Marseille

"Formal models of visual perception based on cortical architectures"

I will show the integration of geometric models of visual perception with dimensionality reduction techniques. Starting from the model of association fields introduced by Citti and Sarti [2], which gives a justification of perceptual completion based on the functionality of the primary visual cortex (V1), it is possible to model the cellular connectivity by solving systems of stochastic differentitalequations as described in [9] and [1], obtaining the probability density that is the probability of connection between simple cells in V1 [1]. Starting from these kernels, the problem of grouping is faced by means of spectral analysis of suitable affinity matrices [2,7]. For the numerical simulations, I have consider particularly Kanizsa figures as clear examples of problems of visual perception [5], and retinal images, to afford problems of grouping during the tracking of blood vessels [4]. Finally I will show a comparison between the results obtained through these models with functional data fMRI, in order to afford the problem of identific the band reconstruction of images from fMRI activity [3,6,8].

References
[1] D. Barbieri, G. Citti, G. Cocci, A. Sarti, A cortical-inspired geometry for contour perception., 2013.
[2] G. Citti and A. Sarti, A cortical based model of perceptual completion in the roto-translation space., Journal of Mathematical Imaging and Vision, 24(3):307-326, 2006.
[3] K. N. Kay, T. Naselaris, R. J. Prenger, and J. L. Gallant. Identifying natural images from human brain activity. Nature, 452(7185): 352-355, 2008.
[4] M. Favali, S. Abbasi-Sureshjani, B. H. Romeny, and A. Sarti. Analysis of vessel connectivities in retinal images by cortically inspired spectral clustering. Journal of Mathematical Imaging and Vision, 56(1):158-172, 2016a.
[5] M. Favali, G. Citti, A. Sarti, Local and global gestalt laws: A neurally based spectral approach, Neural Computation, February 2017, Vol. 29, No. 2, Pages: 394-422.
[6] T. Naselaris, R. J. Prenger, K. N Kay, M. Oliver, and J. L. Gallant. Bayesian reconstruction of natural images from human brain activity. Neuron, 63(6):902-915, 2009.
[7] A. Sarti, G. Citti, The constitution of visual perceptual units in the functional architecture of V1, Journal of computational neuroscience, 38(2):285–300, 2015.
[8] B.Thirion, E. Duchesnay, E. Hubbard, J. Dubois, J. Poline, D. Lebihan, and S. Dehaene. Inverse retinotopy: inferring the visual content of images from brain activation patterns. Neuroimage, 33(4):1104-1116, 2006.
[9] L.R. Williams, D.W. Jacobs, Stochastic completion fields., ICCV Proceedings, 1995.

For any question, feel free to contact:
Demian Battaglia (demian.battaglia@univ-amu.fr) or Benjamin Morillon (bnmorillon@gmail.com)