Marcelo O. Magnasco, Ph.D.
Professor
Laboratory of Mathematical Physics
E-mail: magnasco@rockefeller.edu
Dr. Magnasco leads a group of physicists who look at living beings as a source of inspiration for creating new mathematical
descriptions of nature. His neurobiology studies have recently focused on sensory processing: the neural encoding of sound,
primary visual cortex and the structure of the visual environment, and models of adult neurogenesis in the olfactory bulb.
Using mathematical concepts to describe what biologists deem complex phenomena — observations that had previously been considered too random to be characterized by one equation
or theory — Dr. Magnasco is modeling the complexity, organization and self-assembling properties of living organisms. Some of the problems he is working to solve include
determining how imprecise and noisy molecular machinery perform accurate tasks and understanding how the brain makes complex and accurate computations using unreliable neurons.
Although Dr. Magnasco’s lab is primarily theoretical, he often works in direct experimental collaborations using a variety of computational techniques, such as computerized histology, image analysis and clustering analysis of microarray data.
His neurobiology studies have focused on sensory processing, including auditory, visual and olfactory. In the visual system, he has studied the reliability of neuronal firing in the lateral geniculate nucleus and primary visual cortex, and the statistical structure of the visual environment. In the olfactory system, he has worked to understand the role of adult de novo neurogenesis in the olfactory bulb.
A substantial amount of Dr. Magnasco’s sensory-processing studies have centered on the auditory realm. Dr. Magnasco is looking at sound processing from several different levels: from dynamical models of hair-bundle motion and models of the dynamics and tuning characteristics of the cochlea to higher-level studies of auditory encoding. In collaboration with Rockefeller’s James Hudspeth, Dr. Magnasco has created a mathematical model of a “trapdoor amplifier” in the hair cells of the inner ear — research that challenged some of the most basic assumptions about how human ear processes sound.
Dr. Magnasco has also directed his auditory studies toward birdsong. By following expression of a gene called ZENK, members of the Magnasco lab were able to watch song learning and memory at the cellular level in the brains of canaries. Most recently, in a sound analysis breakthrough, Dr. Magnasco created an algorithm that transforms sound into visual representations with far more accuracy than anything currently available and that may use the same type of method as the human brain.
In addition to his work on sensory systems, Dr. Magnasco has studied dynamics in a number of molecular systems. Older work centered on stochastic dynamics of motor proteins and other molecular machinery, including the development of a general framework for molecular-level internal combustion engines. More recently, he proposed a mechanism (based on kinetic proofreading) for how topo-isomerases disentangle knots and links in DNA. He’s also using microarrays to pursue the study of gene expression networks, such as those that occur in neural and embryonic stem cells.
Experiments currently under way in the lab center on psycho-acoustic studies in humans and electrophysiological recordings in the auditory pathways of rodents.
CAREER
Dr. Magnasco graduated from the University
of La Plata in Argentina with a bachelor’s
degree in physics in 1987. He received his Ph.D.
in physics from the University of Chicago in
1992, then came to Rockefeller as a postdoc
and visiting scientist at the NEC Research
Institute. The following year, he was named
assistant professor and head of lab as the first
faculty member recruited to Rockefeller’s Center
for Studies in Physics and Biology. He was
promoted to associate professor in 1999 and
professor in 2003. From July 2002 through July
2003, he also worked as a research scientist at
UNESCO’s Abdus Salam International Centre
for Theoretical Physics.
In 1991, Dr. Magnasco was named the
University of Chicago’s Sydney Bloomenthal
Dissertation Fellow and the William Rayney
Harper Dissertation Fellow.
