Giacomo Benvenuti

Ph.D Student in Neuroscience
CNRS & Université de la Méditerranée
31 chemin J. Aiguier (Bat N, office room 029 / Lab 118)
13402 Marseille Cedex 20
Phone: 33 (0) 4 91 16 46 53 (Office) / 45 81 (Lab)
Fax: 33 (0) 4 91 16 49 69.

Email: benvenuti at incm.cnrs-mrs.fr

Curriculum Vitae

Research interests

KEY WORDS: Vision - Motion integration - Predictive population coding - Contextual effect - V1 - Horizontal connections - Extracellular recording in awake monkey - Voltage sensitive dyes imaging (VSDi) - FACETS-ITN - ELPHY (Softwere)

The aim of my research is the investigation of dynamic mechanisms of motion integration and neural population representation in visual cortex.

A visual signal needs time to be processed and transmitted from retina to visual cortex, generally in the order of 30-100 ms (Maunsell et al. 1992).
A moving object could cover a considerable distance in this time and therefore we should percept it behind its real position. But in general it does not happen and we percept a proper approximation of the real object position (a good example of this is the flash lag effect, see Nijhawan R. 1994).
This may be the result of an anticipatory integration process that predicts the current position of the moving object from its past position and velocity. Such motion anticipation was assumed to be controlled by high-level motion areas of the visual cortex (cortical feedback loops) but unexpectedly it was also observed as early as the retina (Berry et al. 1999, Gegenfurtner K. 1999) and primary visual cortex  (V1) circuits  (Guo K. et al. 2007).

My current project consists in studying the role of lateral and feedback interactions in integrating and anticipating simple stimuli motion information (as a bar moving along different trajectories at different orientations) in V1 of the awake monkey.

My experimental approach involves the analysis of V1 activity from single neuron (extracellular electro-physiological recording) to neural population (voltage sensitive dyes imaging) level of study on alert monkey.

We expect to confirm our preliminary observations (results obtained by A. Boonman) and extend our understanding regarding the modulation of V1 neurons activity by prior stimuli in its association field by charactarizing the distribution of “neural population activation� (Erlhagen W. et al. 1999) in response to a simple moving stimulus in V1.

The Ph.D program I am carrying on is embedded in an European Integrated Training Network, named FACETS ITN (Fast Analog Computing with Emergent Transient States). FACETS is an European collaborative project linking biological experiments on cortical dynamics, physics and computational neuroscience to implement these network into Very­ Large Scale Integration (VLSI) hardware circuits

Read more on my main web page