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Noga Vardi

Noga Vardi 

Dr. Vardi received her BS in biology from Hebrew university and her Ph.D from Cornell university. She is currently a professor of neuroscience, University of Pennsylvania.

Perception is an incredibly abstract and complicated brain function, which enables us to see the world through the filters of the sensory systems. Sensory neurons transduce physical signals (light, sound waves, molecules in the air) into electrical signals, and these are communicated between neurons. It is the ensemble of these neurons’ activity that is interpreted as a familiar face, a pleasant music, an obnoxious smell, etc. Neurons communicate by a variety of cellular and molecular mechanisms whose principals and details Neuroscience is seeking. 

Dr. Vardi deciphers some of the principal mechanisms of perception, a brain function which enables us to see the world through the filters of the sensory systems. The vision retina is her model system. Dr. Vardi addresses questions concerning the precise connections between neurons, both at the morphological and molecular levels. She figures out what information is being communicated by deciphering chemical released from a cell and the receptors which receive particular chemicals. The retina is used as a model system for signal processing because it has several advantages over centers in the brain. first, the input is well defined: it is the pattern of light and dark "dots" that falls on the retina. second, the output, which is carried out of the retina by ganglion cells, has been thoroughly studied. Third, the anatomy of the retinal is well studies both on the light and electron microscopic levels. the knowledge is so detailed that the number of synapses between specific cell type is known. Finally, the questions regarding signal processing are well defined: photoreceptors (through retinal circuits) transfer information to ganglion cells under a wide range of luminances, and they do it very reliably! To signal reliably, the retina has to employ gain control and noise removal mechanisms. the key question is: what is the molecular basis of these principal mechanisms? Dr. Vardi's work figuring out the chemical architecture of the circuit will decipher this question.