Tom Duke

Physical basis of hearing Self-organization of the cytoskeleton Cell motility Signal transduction mechanisms Neural networks Bionanotechnology Contact details: Office: Room 3C2 Tel: +44 (0)20 7679 3496 Ext: 33496 Fax: +44 (0)20 7679 0595 Email: t.dukeucl.ac.uk

My research concerns the physical modelling of biological systems, typically at the cellular or supramolecular level, together with some more applied work in bionanotechnology. Topics of current interest include the active mechanism of sound detection in the inner ear, the organization of cytoskeletal filaments in growing cells, mechanisms of cell motility, and information processing in networks of neurons.

Other activities

Adjunct Associate Editor, Physical Review Letters.
Editorial Board, Physical Biology.

Recent publications

"Active traveling wave in the cochlea" [PDF File]
T. Duke & F. Jülicher, Phys. Rev. Lett. 90, 158101 (2003)

"Two adaptation processes in auditory hair cells together can provide an active amplifier" [PDF File]
A. Vilfan & T. Duke, Biophys. J. 85, 191 (2003)

• BA (natural sciences), University of Cambridge (1986)
• PhD (theoretical physics). University of Cambridge (1989)
• 1990-1992: Marie Curie Fellow, ESPCI, Paris
• 1993-1995: Research Staff Member & Lecturer, Princeton University
• 1995-2002: Royal Society University Research Fellow, University of Cambridge
  
• 1996: Visiting Scientist, University of Strasbourg
  
• 1998: Visiting Professor, Niels Bohr Institute
  
• 1999: Visiting Scientist, Institut Curie1998-2007: Fellow and Lecturer in Physics, Trinity College, Cambridge
• 2002-2007: Lecturer, then Reader in Biological Physics, University of Cambridge
  
• 2007-present: Professor of Physics, UCL

The main focus of hearing research in recent years has been the nature of the active process that enhances sound detection in the inner ear. We have advanced the general concept of self-tuned criticality to explain how the active system works. The cochlea contains a set of force-generating dynamical systems, each of which is maintained at the threshold of an oscillatory instability by feedback control. Poised at the critical point, on the verge of vibrating, each oscillator is especially responsive to periodic disturbances at its own characteristic frequency. The active amplification provided by the set of critical oscillators is ideally suited to the ear's needs, since it provides frequency selectivity, exquisite sensitivity and a wide dynamic range.  Recent experiments on the amphibian hair cells have demonstrated that their mechanosensory apparatus – the hair bundles - oscillate actively and respond to stimuli as predicted by this general model (see right). Sound entering the mammalian cochlea generates a wave that carries energy to a particular, frequency-dependent place. The nonlinear properties of this wave can be understood by positing that the motion of the cochlear partition is driven by a set of critical oscillators, whose characteristic frequencies decrease from base to apex (see below).