4 YEAR PhD IN NEUROSCIENCE
Function and development of hippocampal neural circuits
My research interests lie in the neuronal basis of spatial cognition, learning and memory. We study the function of neurons and neuronal circuits in the hippocampal formation. We use a combination of electrophysiological and behavioural techniques, in order to directly assay the function of hippocampal neurons during awake behaviour.
Our research focuses on the neurons in the hippocampal formation that code for an organism’s position and orientation in space (‘Place cells’1, ‘Head-direction cells’2 and ‘Grid Cells’3). One major research focus of the lab is how and when these cell types emerge in post-natal development. This involves recording from hippocampal neurons during development, and observing the effects of manipulating the rearing environment. We are also interested in the neural circuits supporting spatial cognition in the adult. In particular, using pharmacological and optogenetic techniques, we are currently studying the nature of the interactions between different cell types in the hippocampal formation.
PhD projects are can be designed to fit the interests of the laboratory and the individual student. Projects currently under way in the lab include:
1) The development of sensory responses in place cells. What are the sensory cues that support place cell firing in early development, and are there any particular environmental features that are critical for spatially-tuned neuronal firing?
2) The role of early experience in the development of the hippocampus. In particular, what is the long-term effect of visual deprivation on the spatial cells in the hippocampal formation?
3) The application of virtual-reality technology4 to early post-natal development. By using this technique, we will be able to study hippocampal development using in vivo imaging and intra-cellular recording.
4) Using optogenetics to control spatial cell activity, and thereby tease apart the relationships between different spatially-responsive cell types.
1 O'Keefe J, Dostrovsky J. (1971) The hippocampus as a spatial map. Preliminary evidence from unit activity in the freely-moving rat. Brain Res. Nov;34(1):171-5.
2 Taube JS, Muller RU, Ranck JB Jr. (1990). Head-direction cells recorded from the postsubiculum in freely moving rats. I. Description and quantitative analysis. J Neurosci. Feb;10(2):420-35.
3 Hafting T, Fyhn M, Molden S, Moser MB, Moser EI. (2005) Microstructure of a spatial map in the entorhinal cortex. Nature. Aug 11;436(7052):801-6.
4 Harvey CD, Collman F, Dombeck DA, Tank DW. (2009) Intracellular dynamics of hippocampal place cells during virtual navigation. Nature. Oct 15;461(7266):941-6.
Wills TJ, Barry C and Cacucci F (2012) The abrupt development of adult-like grid cell firing in the medial entorhinal cortex. Front. Neural Circuits 6:21
Wills TJ, Cacucci F, Burgess N, O'Keefe J (2010) Development of the hippocampal cognitive map in preweanling rats. Science, 328:1573-6.
Cacucci F, Yi M, Wills TJ, Chapman P, O'Keefe J. (2008). Place cell firing correlates with memory deficits and amyloid plaque burden in Tg2576 Alzheimer mouse model. PNAS, 105(22), 7863-7868.