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Ralph Greenspan, PhD

Ralph Greenspan, PhD

Associate Director, Kavli Institute for Brain and Mind

Contact Information

Office tel: 858-822-7657
Lab Website:

Research Title
Gene and neural networks underlying behavior and cognition in Drosophila and other invertebrates.

Research Description
Our research focuses on genetic influences on behavior. In the fruit fly Drosophila, these studies have included: the demonstration that the fly has a sleep-like behavior similar to that of mammals, the introduction of highly localized genetic alterations in the nervous system to manipulate behavior, molecular identification of genes causing naturally occurring variation in behaviors such as foraging, geotaxis, and aggression, studies of the physiology and circuitry underlying sleep, arousal, and attention, and studies of the structure and function of gene networks.

In addition to studying these questions in Drosophila, we are now also working with simpler organisms in an effort to be able to manipulate and monitor activities at the whole-network scale. For neuronal networks, we are using optical imaging of whole nervous systems in small jellyfish medusa, and for gene networks we are analyzing whole-genome scale expression patterns in response to manipulations in Paramecium and cyanobacteria. In all of the network studies, we use behavioral output (e.g., phototaxis, chemotaxis, and circadian rhythms) as the phenotype to monitor in conjunction with analysis of network states.

Greenspan, R.J. (2009) Selection, gene interaction, and flexible gene networks. Cold Spring Harbor Symp. Quant. Biol. 74: 131-138.

Kent, C., Daskulchuk, T., Cook, L., Sokolowski, M.B., and Greenspan, R.J. (2009) The foraging gene in D. melanogaster mediates metabolic as well as behavioral plasticity. PLoS Genetics 5: e10010609.

Foltenyi, K., Andretic, R., Newport, J.W., and Greenspan, R.J. (2007) Neurohormonal and neuromodulatory control of sleep in Drosophila. Cold Spring Harbor Symp. Quant. Biol. 72: 565-571.

Dierick, H.A. and Greenspan, R.J. (2006) Molecular analysis of flies selected for aggressive behavior. Nature Genetics 38: 1023-1031.

Greenspan, R.J. and van Swinderen, B. (2004) Cognitive consonance: Complex brain functions in the fruit fly and its relatives. Trends in Neurosciences 27: 707-711.

van Swinderen, B. and Greenspan, R.J. (2003) Salience Modulates 20-30 Hz Brain Activity in Drosophila. Nature Neuroscience 6: 579-586.