Timothy O’Leary PhD

Timothy O'Leary


Publications:
2010
  Algorithms for automatic neuron tracing in noisy 3D image stacks
Knowles-Barley, S, Phillipson, G, Teriakidis, A, Sterratt, D, Larkworthy, T, O'Leary, T, Down, MP, Hennig, M, Withers, JPJ & Hull, M 2010, 'Algorithms for automatic neuron tracing in noisy 3D image stacks' Neuroscience Day 2010, Edinubrgh, United Kingdom, 29/03/10 - 29/03/10, .
General Information
Organisations: Institute for Adaptive and Neural Computation .
Authors: Knowles-Barley, Seymour, Phillipson, Graeme, Teriakidis, Adrianna, Sterratt, David, Larkworthy, Thomas, O'Leary, Timothy, Down, Matthew P., Hennig, Matthias, Withers, James P. J. & Hull, Michael.
Publication Date: 2010
Publication Information
Category: Poster
Original Language: English
2008
  Conductance changes underlying homeostatic regulation of intrinsic excitability in hippocampal neurons
O'Leary, T, van Rossum, MCW & Wyllie, DJA 2008, 'Conductance changes underlying homeostatic regulation of intrinsic excitability in hippocampal neurons' Society for Neuroscience Annual meeting, 2008, Washington DC, United States, 15/11/08 - 19/11/08, .
General Information
Organisations: Centre for Integrative Physiology.
Authors: O'Leary, Timothy, van Rossum, Mark C. W. & Wyllie, D. J. A..
Publication Date: 2008
Publication Information
Category: Poster
Original Language: English
  Homeostatic regulation of intrinsic excitability in hippocampal neurons: response to chronic depolarisation
O'Leary, T, Van Rossum, M & Wyllie, D 2008, 'Homeostatic regulation of intrinsic excitability in hippocampal neurons: response to chronic depolarisation' 6th FENS Forum of European Neuroscience, Geneva, Switzerland, 12/07/08 - 16/07/08, .
For the nervous system to function properly, activity levels must be regulated. The favourite candidate mechanism for learning and memory in the mammalian CNS is Hebbian learning – a process which tends to strengthen connectivity between excitatory cells in response to correlated firing patterns. In isolation, this constitutes a positive feedback loop, destabilising the average activity level in an intact network [1, 3]. It is therefore likely that homeostatic mechanisms exist to co-regulate activity on a cellular level, and several candidate mechanisms have been characterised to date [2, 3]. Here we describe an in-vitro model for homeostatic control of intrinsic excitability. We find that cultured hippocampal neurons respond to chronic depolarisation over a period of days by attenuating their response to injected current. Cells grown in depolarising medium containing 15 mM KCl exhibited a tenfold increase in the amount of steady current required to induce spiking (9.7+/-3.5 pA for n=25 control cells; 94.5+/-16.0 pA for n=18 treated cells). This effect was found to depend on the level of depolarisation and the length of treatment, and is accompanied by a decrease in voltage-gated sodium conductance in the cells. Consistent with these observations is a prominent hyperpolarising shift in resting membrane potential relative to control (-50+/-1 mV vs. -58+/-1 mV) and a drop in input resistance (790+/-140 MOhm vs. 330+/-60 MOhm). Using these data to parameterise a conductance-based computer model offered insight as to whether they could account for the observed differences in excitability.
General Information
Organisations: Centre for Integrative Physiology.
Authors: O'Leary, Timothy, Van Rossum, Mark & Wyllie, David.
Publication Date: 2008
Publication Information
Category: Poster
Original Language: English
2006
  Glycine potency among recombinant N-methyl-D-aspartate receptor subtypes is influenced by the S2 glutamate binding region of the NR2 subunit
Chen, PE, Erreger, K, O'Leary, T, Livesey, M, Traynelis, SF & Wyllie, DJA 2006, 'Glycine potency among recombinant N-methyl-D-aspartate receptor subtypes is influenced by the S2 glutamate binding region of the NR2 subunit' Society for Neuroscience 36th Annual Meeting (SfN), Atlanta, GA, United States, 14/10/06 - 18/10/06, .
General Information
Organisations: Centre for Integrative Physiology.
Authors: Chen, P. E., Erreger, K., O'Leary, Timothy, Livesey, M., Traynelis, S. F. & Wyllie, D. J. A..
Publication Date: 2006
Publication Information
Category: Poster
Original Language: English

Projects:
Homeostatic plasticity of Intrinsic Excitability (PhD)