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Fabrizio Gabbiani
Baylor College of MedicineDepartment: NeuroscienceAddress: One Baylor Plaza, Rm. S557C Houston TX 77030 Phone: 713 798 1849 Fax: 713 798 3946 Email: gabbiani@bcm.edu Web: glab.bcm.tmc.edu |
Education
Ph.D., Theoretical Physics, Swiss Federal Institute of Technology, Zürich
Honors
Roche Research Fellowship
Sloan Fellowship in Theoretical Neuroscience
Alfred P. Sloan Research Fellow
Woods Hole Faculty Summer Research Fellowship
Research Topic
Biophysics of information processing in the nervous system
Research Description
The laboratory is interested in computational aspects of sensory information processing from the single cell to the network level. The mechanisms underlying information processing by neurons and neuronal networks are currently the subject of intense investigations. In visual sensory systems, significant progress has been made in understanding the circuitry and the response dynamics underlying the receptive field properties of visual neurons. Our understanding of the cellular and dendritic mechanisms that could contribute to the processing of sensory information in single neurons has also been greatly increased. However, still very little is known about how the biophysical properties of single neurons are actually used to implement specific computations. Two types of neuronal computations thought to be fundamental to the processing of information within the nervous system are the multiplication of independent signals and invariance of neuronal responses.
We are studying collision avoidance in the visual system of the locust as a model to investigate these questions. The locust optic lobes possess an identified neuron, the lobula giant motion detector neuron (LGMD), which responds vigorously to objects approaching on a collision course with the animal (looming stimuli). The firing rate of the LGMD peaks when an approaching object approximately reaches a constant angular threshold size on the retina, suggesting that angular threshold might be the variable used to trigger escape and collision avoidance behaviors. The time-course of the firing rate of this neuron in response to looming stimuli is best described by multiplying two inputs impinging on the dendrites of the LGMD. One input is excitatory and sensitive to motion while the other input is inhibitory and sensitive to size. Current evidence suggests that this multiplication is in part implemented within the dendritic tree of the neuron. Furthermore, the response of the LGMD is invariant to a wide range of loooming stimulus parameters, including the contrast, the texture, the angle of approach and the particular shape of the approaching object. Because the LGMD can be reliably identified from animal to animal and recorded intracellularly for extended periods of time, it offers an ideal model to investigate the biophysical mechanisms underlying these computations.
Selected Publications
- Peron SP Krapp HG Gabbiani F (2007) Influence of electrotonic structure and synaptic mapping on the receptive field properties of a collision-detecting neuron. J Neurophysiol, 97:159-177
- Gabbiani F Krapp HG (2006) Spike-frequency adaptation and intrinsic properties of an identified looming-sensitive neuron. J Neurophysiol, 96:2951-2962
- Krahe R Gabbiani F (2004) Burst firing in sensory systems. Nat Rev Neurosci, 5:13-23
- Gabbiani F (2003) Interpolating between cellular biophysics and computation in single neurons. Neuron, 37:977-987
- Gabbiani F Krapp HG Koch C Laurent G (2002) Multiplicative computation in a visual neuron sensitive to looming. Nature, 420: 320-324.
- Gabbiani F. Rate coding and signal processing Handbook of Brain Theory and Neural Networks (Arbib M ed) MIT Press: Cambridge MA (2003) 0, 941-945
- Gabbiani F. A switch for oscillatory bursting [News and Views] Nat Neurosci (2003) 6, 212-213
- Gabbiani F. Interpolating between Cellular Biophysics and Computation in Single Neurons [Preview] Neuron (2003) 37, 890-891
- Peters RJ, Gabbiani F, Koch C. Human visual object categorization can be described by models with low memory capacity Vision Res (2003) 43, 2265-2280
- Krahe R, Gabbiani F. Bursting Activity in Weakly Electric Fish Computational Neuroscience, a comprehensive approach (J. Feng, ed). CRC Press (2004) 0, 215-252
- Gabbiani F, Krapp HG, Hatsopoulos N, Mo CH, Koch C, Laurent G. Multiplication and stimulus invariance in a looming-sensitive neuron J Physiol Paris (2004) 98, 19-34
- Gabbiani F, Cohen I, Laurent G. Time-dependent activation of feed-forward inhibition in a looming-sensitive neuron J Neurophysiol (2005) 94, 2150-61
- Fotowat H, Gabbiani F. Relationship between the phases of sensory and motor activity during a looming-evoked multistage escape behavior J Neurosci (2007) 27, 10047-10059
- Peron SP, Krapp HG, Gabbiani F. Influence of electrotonic structure and synaptic mapping on the receptive field properties of a collision-detecting neuron J Neurophysiol (2007) 97, 159-177
- Peron SP, Gabbiani F. Role of Spike Frequency Adaptation in Shaping Neuronal Response to Dynamic Stimuli Biol Cybern (2009) 100, 505-520
- Peron SP, Gabbiani F. Spike frequency adaptation mediates looming stimulus selectivity in a collision-detecting neuron Nat Neurosci (2009) 12, 318-326
Lab Members
Lab Photos
Last edited on: June 22, 2007