Dr Sidney I. Wiener DR2, CNRS Tel : (00 33) 1 44 27 16 21 : sidney.wiener AT college-de-france.fr

• Phd students
• Our Research Interests
• Academic credentials
• My scientific career
• Projects

Phd students

Our Research Interests

How does brain activity give rise to cognitive functions, emotion and awareness? To address this question we study the sparks of electricity (action potentials) that individual neurons engage as signals. In order to benefit from the vast experimental neurobiology and psychology literature, we employ laboratory rats as an experimental model for our experiments (in addherence with ethical standards and local, national and international laws).

Academic credentials

Habilitation à diriger des recherches, 31 Mai 1995, Université Pierre et Marie Curie, Paris.

Ph.D. Neuroscience and Biophysics, 1983, Michigan State University, East Lansing, Michigan 48823 USA. (Advisor: Dr JI Johnson, Depts Anatomy, Biophysics and Zoology; The Neuroscience program at Michigan State at that time was organized by Professors Glenn Hatton and Ralph Pax. Drs Michael Ostapoff and Sharleen Sakai made important contributions to my thesis research)

M.S. Biophysics, 1980, Michigan State University, East Lansing, Michigan 48823 USA. (Advisor: Dr Barnett Rosenberg)

B.S. Chemistry (certified, American Chemical Society), 1977, College of William and Mary, Williamsburg, Virginia 23185 USA.

Research program in Paris

Our research program at the CNRS-Collège de France LPPA is centered on, and radiates from, are likely to high level abstract and supramodal activity correlates of hippocampal neurons, cell activities underlie cognitive functions. The most well-known such property is that of the so-called ‘place cell', which discharges selectively as the rat (or monkey or mouse) occupies a restricted area in the local environment. Head direction cells and grid cells are more recent discoveries in this system.

Our principal research questions are:

1. How does the brain elaborate these high level abstract representations?
2. How are these signals engaged by other brain structures to guide behavior?

The first theme has focussed on the role of self-movement information such as vestibular sensory signals in updating head direction and place responses. Although we are acutely interested in the vestibular system, a necessary caveat is that in the intact behaving animal, it is very difficult to apply natural vestibular stimuli. (Generally, we have applied inertial stimuli , like passive translation and rotation, which also stimulates non-vestibular systems including proprioception, visceral receptors as well as provoking postural and oculomotor reflexes and accompanying efferent collateral and proprioceptive pathways.) We use certain experimental protocols to determine the respective roles of different sensory (and motor) signals – a particularly useful one is cue conflict, where different sensory systems carry discordant information.

Reviews of these studies and of other relevant information can be found in:

• Wiener SI (2005) Head direction cells and n eural mechanisms of spatial orientation: Synthesis and perspectives. Dans S.I. Wiener, J.S. Taube (eds.), Head direction cells and the neural mechanisms of spatial orientation , chap 20, MIT Press.

• Wiener SI, Schenk F. (2005) Behavioral studies of directional orientation in developing and adult animals. Dans S.I. Wiener, J.S. Taube (eds.), Head direction cells and the neural mechanisms of spatial orientation , chap 12, MIT Press.

• Zugaro M.B., Wiener S.I. (2005) How visual cues control preferred directions in head direction cells Dans S.I. Wiener, J.S. Taube (eds.), Head direction cells and the neural mechanisms of spatial orientation , chap 4, MIT Press.

• Wiener, S.I., Shibata, R., Tabuchi, E., Trullier, O., Albertin, S.V., Mulder, A.B. (2003) Spatial and behavioral correlates in nucleus accumbens neurons in zones receiving hippocampal or prefrontal cortical inputs dans T.Ono et al, (eds), Cognition and Emotion in the Brain, Elsevier, NY.

• Wiener S.I., Arleo A. (2003). Persistent activity in limbic system neurons: Neurophysiological and modeling perspectives. Journal of Physiology, Paris 97:547-555.

• Wiener, S.I., Berthoz, A., Zugaro, M.B. (2002) Multisensory processing for the elaboration of place and head direction responses in the limbic system. Cognitive Brain Research. 14:75-90.

• Wiener, S.I., Rondi-Reig, L., Zugaro, M.B. (2001) Comprendre les fonctions cognitives grâce à l'enregistrement de l'activité neuronale et l'analyse comportementale chez le rat libre de ses mouvements : les bases physiologiques des représentations internes de la topographie de l'environnement. Intellectica 32: 9-44.

• Trullier, O., Wiener, S., Berthoz, A., and Meyer, J.-A. (1997) Biologically-based artificial navigation systems: Review and prospects. Progress in Neurobiology 51: 483-544.

My scientific career

Summer 1976, National Science Foundation Undergraduate Research Program Fellow, Case-Western Reserve University, Cleveland, OH, USA My first introduction to scientific research.

01/1978 - 04/1983 Graduate research assistant, Biophysics and Anatomy Departments, Michigan State University, E. Lansing MI (Funded by International Nickel Co., NIH grants, MSU). Inititation in multidisciplinary, functional integrative systems neuroscience with a strong basis in comparative neuroanatomy of sensory systems.

Projects

Two projects, ICEA and BACS, are Integrative Projects (IPs) in the European Community (EC) Information Society Technologies (IST) Cognitive Systems (CogSys)
program (http://cordis.europa.eu/ist/cognition/index.html).

ICEA www.iceaproject.eu “ IST 027819 ICEA ( Integrating Cognition, Emotion and Autonomy ) is a four-year project, funded by IST Cognitive Systems Unit . The ICEA Project is focused on brain-inspired cognitive architectures, robotics and embodied cognition, bringing together cognitive scientists, neuroscientists, psychologists, computational modelers, roboticists and control engineers.

The primary aim of the project is to develop a cognitive systems architecture integrating cognitive, emotional and bioregulatory (self-maintenance) processes , based on the architecture and physiology of the mammalian brain .

The twofold hypothesis behind this research is that:

• the emotional and bioregulatory mechanisms that come with the organismic embodiment of living cognitive systems also play a crucial role in the constitution of their high-level cognitive processes, and
• models of these mechanisms can be usefully integrated in artificial cognitive systems architectures, which will constitute a significant step towards truly autonomous robotic cognitive systems that reason and behave in accordance with energy and other self-preservation requirements.

In ICEA we will develop a new generic autonomous agent architecture based on the extraction of control design patterns from bioregulatory, emotional and cognitive control loops based on the architecture and physiology of the rat brain.” (from the Web site)

Our team's role in ICEA is to study the neural activity and ensemble dynamics underpinning cognitive functions in rats as they acquire, recall and choose between complementary strategies for goal directed action. Recordings involve hippocampus, three parts of striatum, prefrontal cortex and amygdala in order to determine coordination between different structures during shifts in strategy.

BACS http://www.bacs.ethz.ch/ (Bayesian Approach to Cognitive Systems)

“Contemporary robots and other cognitive artifacts are not yet ready to autonomously operate in complex real world environments. One of the major reasons for this failure in creating cognitive situated systems is the difficulty in the handling of incomplete knowledge and uncertainty. By taking up inspiration from the brains of mammals, including humans, the BACS project will investigate and apply Bayesian models and approaches in order to develop artificial cognitive systems that can carry out complex tasks in real world environments. The Bayesian approach will be used to model different levels of brain function within a coherent framework, from neural functions up to complex behaviors. The Bayesian models will be validated and adapted as necessary according to neuro-physiological data from rats and humans and through psychophysical experiments on humans. The Bayesian approach will also be used to develop four artificial cognitive systems concerned with (i) autonomous navigation, (ii) multi-modal perception and reconstruction of the environment, (iii) semantic facial motion tracking, and (iv) human body motion recognition and behavior analysis. The conducted research shall result in a consistent Bayesian framework offering enhanced tools for probabilistic reasoning in complex real world situations. The performance will be demonstrated through its applications to driver assistant systems and 3D mapping, both very complex real world tasks.” (from the Web site)

In BACS we examine the adequacy of a Bayesian approach for describing spatial navigation processes at the levels of

•  How individual spikes predict behaviors like head orientation.

•  How the co-activation of a subset of neurons in a single neuronal ensemble activity predicts future activation patterns over time and behavioral states.

Specifically, our team provides neurophysiological as well as behavioral data to test (and eventually improve) hypotheses about Bayesian inference. This involves a data base from hundreds of recording experiments in several types of mazes.

Another project NeuroProbes is an IP in the EC IST program “Integrating and strengthening the European research area (2002-2006)”

NeuroProbes http://naranja.umh.es/~np/index.php “NeuroProbes is a European Project aiming at developing a system platform for the scientific understanding of cerebral systems, and for the treatment of the associated diseases. The work will produce an integrated tool that combines multiple functions to allow electrical as well as chemical sensing and stimulation of neurons. Fourteen partners, from all over Europe and both from academic and industrial worlds, form the NeuroProbes consortium.

The aim of the proposed research is to develop a system platform that will allow an extremely wide series of innovative diagnostic and therapeutic measures for the treatment and for the scientific understanding of cerebral systems and associated diseases. The proposed work will enable a new integrated tool that combines multiple functions to allow electrical recording and stimulation as well as chemical sensing and stimulation. The resulting potential is expected to lead to a new era of work in the field of fundamental, scientific, as well as clinical brain research.” (from the Web site)

Our team's roles in Neuroprobes:

•  Validation of the developed fixed arrays of silicon-based microelectrodes arrays through recording experiments in rat hippocampal system

•  High population sampling recordings from hippocampal neurons will be tested to determine the nature of functional coupling between ‘place cells' representing overlapping places in the environment, and their dynamic changes over time such as Hebbian-like plasticity processes.

•  Establish relationship between local field potentials and activity in neurons of the hippocampal ensembles

•  Histopathology studies following prototype implantations in rats

•  Development of spike discrimination infrastructure for novel configurations for high-density recording in brain micro-domains

•  software development

•  optimise array spacing

•  Development of data management and ensemble analyses.

* The first person plural is used because similar and complementary research is carried out in parallel by many groups around the world, and also because this work is carried out in collaboration.