The flow of information reaching sensorium of living organisms is greatly determined by patterns of their interaction with the environment. During the last decade, the idea that perception is an active process that depends upon an organism’s behavior and knowledge of the environment has been accepted increasingly. The broad acceptance of vision as an active process is partially attributable to the accumulation of neurophysiological data revealing many of the diverse cerebral mechanisms underlying the active nature of visual perception.  These mechanisms are thought to control the flow of visual information while taking cognitive states and behavioral context into account.

   The mechanisms controlling information flow in the visual system can broadly be segregated into three groups:  (I) arousal mechanisms mediated by modulation of neural responses by ascending activating system; (II) attention/intention mechanisms that endow representations of visual information with behavioral relevance; (III)  cognitive contextual mechanisms that integrate visual information based on the prior knowledge about the structure of the environment.  Presumably, the last two mechanisms are implemented via cortico-cortical lateral and feedback connections as well as through the feedback from subcortical structures.

   The goal of this ASI is to explore the role of these three fundamental types of modulation of neuronal signaling on visual perception.  The ASI will examine recent advances in deciphering these modulatory mechanisms and will draw implications for coding and computational basis of visual perception.

    The ASI will provide a medium for the interested researchers and engineers (mainly postdoctoral and higher level) of relevant areas (neurophysiology, cognitive neuroscience, mathematics, physics, computer science) from both NATO and Partner States to learn about the latest advances in neuronal visual information processing from experts of visual neuroscience, and initiate mutual collaborative projects.

    Format:  One hour lectures will take place every morning and early afternoon.  They will be followed by 15 minute discussion periods.  During the second half of the day, participants will have an opportunity to present their work either in a 15 minute oral presentation or the poster format.  Short series of participant presentations will be followed by a panel discussion.

   Living expenses of the participants will be covered by a grant for all 10 days.  A limited number of travel fellowships will be offered to selected participants.  The National Science Foundation offers nearly-full travel support for a limited number of applicants that are U.S. residents and who are close to defending their thesis or have defended it whithin last three years.  If you would like to apply for this ASI, please fill out this FORM.

July 13:State-dependent modulation of  visual processing: Subcortical pathways.  Moderator: prof. T.Albright, Salk Institute
 

8:00	Breakfast
9:00	Modulation of visual input to cortex.  Overview of the function of the dorsal lateral genicuate nucleaus. P. Heggelund,Oslo University
10:00	Coffee break
10:20	Signal processing in the lateral geniculate nucleus. P. Heggelund,Oslo University
11:20	Modulation of LGN responses by the ascending activating system. O.Ruksenas,Vilnius University
12:20	Lunch
13:20	Group work
16:00	Mathematical modeling of receptive fields in the low-level visual system of the cat I. G. Einevoll, Agricultural University of Norway
17:00	Coffee break
17:20	The dynamic response characteristic of cells in the cat.F. Woergoetter, University of Stirling
18:20	Discussion
19:00	Dinner

July 14:State-dependent modulation of  visual processing:  Cortex.  Moderator: prof. P.Heggelund, Oslo University
 

8:00	Breakfast
9:00	Cortical cell responses - the deceiving concept of "receptive fields". I.F. Woergoetter, University of Stirling
10:00	Coffee break
10:20	Mathematical modeling of receptive fields in the low-level visual system of the cat II. G. Einevoll, Agricultural University of Norway
11:20	Discussion
12:00	Lunch
13:00	Group work
16:00	Contributed presentations (15 min talks + 5 min discussions): F. Tennigkeit. Neuromodulation of dynamical networks in visual cortex G.Svirskis. Influence of synaptic inut temporal correlation and intrinsic membrane properties on synchronisation of spikes between model neurons. J. vad der Want. Neuronal circuitry in the pretectal and accesory optic system. U.Halici. Time frequency analysis of visual evoked potentials in relation to interhemispheric transfer
17:20	Coffee break
17:40	Cortical processing of visual motion. T.D. Albright, The Salk Institute
18:40	Discussion
19:00	Dinner

July 16: Linking Neurons and Perception II. Moderator: Prof. J. Kulikowski, UMIST
 

8:00	Breakast
9:00	Neural basis of fundamental filters in vision. J. Kulikowski, UMIST, Manchester
10:00	Cortical mechanisms of binocular depth perception. A. Parker, Oxford University
11:00	Coffee break
11:20	Is chromatic induction retinal or cortical? C. Wehrhahn, Max Plank Institute, Tübingen
12:20	Lunch
14:00	Trip to Juodkrante
18:00	Discussion
19:00	Dinner

July 17:Attentional Modulation of Visual Representations.  Moderator: prof. G.Boynton, Salk Institute
 

8:00	Brakfast
9:00	Brainmechanisms of visual target selection. G.T. Buracas, The Salk Institute
10:00	Coffee break
10:20	Unbiased Gain Control and Neuronal Synchronization. K. Pavelzik, University of Bremen
11:20	Discussion
12:00	Lunch
13:00	Group work
16:00	Principles of fMR imaging of brain function.G.M. Boynton, The Salk Institute
17:00	Coffee break
17:20	Selective visual processing revealed by fMRI. G.T. Buracas, The Salk Institute
18:20	Discussion
19:00	Dinner

July 18: Integration of Visual Information: Contextual Influences. Moderator: prof. C.Wehrhahn, Max Plank Institute, Tuebingen
 

8:00	Breakfast
9:00	Structure and function of cortico-cortical connections in the primate visual system. J. Bullier, INSERM, Bron/Lyon
10:00	Contextual influence on orientation discrimination of humans and responses of neurons in V1 of alert monkeys. C. Wehrhahn, Max Plank Institute, Tübingen
11:00	Coffee break
11:15	Temporal issues in information processing in the visual system. J. Bullier, INSERM, Bron/Lyon
12:15	Lunch
13:15	Group work
16:00	Contributed presentations (15 min talks + 5 min discussions): M. van Hulle. Modeling motion processing in macaque area MT/V5: From single cells to population codes P.Cavaleri. A gaze-centered template model for heading perception G.McConkie. Perceptual and cognitive determinants of saccade timing during reading
17:00	Coffee break
17:20	Contributed presentations (15 min talks + 5 min discussions): K. Koerding. Learning invariances in a physiologically realistic way A. Paakkonen. Does motion sharpen edges? J. Ammermuller. Ganglion cell activity in the turtle retina is synchronized by microscopic eye movements.
18:20	Discussion
19:00	Dinner

July 19: Integration of Visual Information: Role of Eye Movements. Moderator: Prof. T.Vilis, University of Western Ontario
 

8:00	Breakast
9:00	Eye position in visual perception and action. T. Vilis, University of Western Ontario
10:30	Coffee break
10:30	Is the Homunculus just watching TV? T.Zador, Cold Spring Harbor Lab
11:15	The perceptual consequences of Listing's Law. T. Vilis, University of Western Ontario
12:15	Lunch
13:15	Group work
16:00	Contributed presentations (15 min talks + 5 min discussions): A.Bertulis. Neurophysiology of color vision C. Heywood. Monkey color vision following ablations of anteror inferotemporal cortex R.C. Baraas. Chromatic components in VEPs to moving isoluminant gratings M.Jurkutaitis. 'Dimming' effect in colour matching explained
17:20	Coffee break
17:40	Contributed presentations (15 min talks + 5 min discussions): P. Benson. Bootstraping natural image categorisation J. Kremlacek. Transient activation invoked by visual motion onset and pattern reversal M.Danilova. What causes detection facilitation of a Gabor patch that is collinear to an illusory contour?
18:40	Discussion
19:00	Dinner

July 20: Neural Codes for Active Vision. Moderator: prof. A. Zador, Cold Spring Harbor Lab
 

8:00	Breakfast
9:00	Voltage gated channels: how they can change information transfer at a single neuron level? G. Baranauskas, Northwestern University
10:00	Signal and noise in cortical circuits.A. Zador, Cold Spring Harbor Lab
11:00	Coffee break
11:15	Dynamic synapses and signal transmission.K. Pavelzik, University of Bremen
12:15	Lunch
14:00	Rapid Population Rate Codes. K. Pavelzik, University of Bremen
15:00	Discussion
15:40	Coffee Break
16:00	Brainstorming the Unsolved Problems of the Neural Basis of Active Vision:  short presentations by the participants of their group work results
19:00	Dinner

July 21:Neural Basis of Active Vision. Moderator: prof. G. Boynton, Salk Institute
 

8:00	Breakfast
9:00	Information processing in the visual system. N. Leibovic, Buffalo University, NY
10:00	Coffee break
10:20	Putting it all together: the closing addres by organizers
10:50	Brunch
11:30	Trip to Vilnius/Departure

Transfer interrupted!

6. Radu I.   HUMAN SUPRACHIASMATIC NUCLEUS IN INTEGRATION OF VISUAL INFORMATION:IMMUNOCYTOCHEMICAL STUDY

Partner Country Director:

Osvaldas  Ruksenas,

Assoc.Prof.   Dr.Biomed.Sci.,

Vilnius University

osvaldas.ruksenas@gf.vu.lt

Scientific Committee:

Geoffrey Boynton, Ph.D., Professor,

Salk Institute
 

Paul Heggelund,  Ph.D., Professor,

Oslo University
 

Andrew Parker,  Ph.D., Professor,

Oxford University