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Joseph O'Neill

Dr Joseph O'Neill

Ser Cymru Fellow

School of Psychology

+44 29206 88916
Tower Building, 70 Park Place, Cardiff, CF10 3AT


Research summary

My research addresses how networks of neurons encode memory in the brain. A particular interest is to identify how the hippocampus and parahippocampal areas of the brain support the formation and consolidation of memory for places and events.  An additional goal is to understand how memories for textures are stored and processed, when they are required to solve a task. Overall our approach is to delineate the what, where and when of memory; that is, what neurons are ‘saying’, where they are sending this information and when this code is transmitted during memory processing.


















Research topics and related papers

Working in the Behavioural Neuroscience Laboratory, our research forms part of one of its core themes, namely understanding the neural basis of learning and memory.  Currently, our work focusses on the role of the subiculum in spatial memory, as well as how tactile information is encoded, stored and utilised in a task.

Mapping subicular mnemonic circuitry

The formation of memory for places and events represents a systems level process that engages multiple parahippocampal and extra-hippocampal brain regions, coordinated by the output from the CA1 region of the hippocampus and the subiculum. In contrast to CA3 and CA1 area place coding, the subiculum code shows diverse spatial properties, providing downstream targets with a complex mix of information. How does this subicular code represent mnemonic information? How does it interact with the CA1 area during learning? How is this information routed to the rest of the brain during different stages of memory formation?   To answer these questions, we use multichannel recordings in freely moving rats combined with optogenetics and chemogenetics.

Cell assembly reactivation/replay in the hippocampus and parahippocampal areas

A growing body of evidence suggests sleep plays a critical role in memory consolidation. The hippocampus partially coordinates this process by reactivating or replaying memory traces, as part of an offline ‘rehearsal’ mechanism.  The subiculum projects to the overwhelming majority of hippocampal target structures and so likely conveys replayed memory traces to parahippocamal regions and beyond.  An important goal for the group is to identify how the subiculum supports consolidation and how this is coordinated with the CA1.

Cortical pathways and synaptic mechanisms for texture discrimination learning in rodents

In collaboration with Kevin Fox and Rob Honey, we aim to apply techniques that can resolve information from the level of the synapse up to the whole brain to understanding the physical basis of learning and memory.    Our component of this project is to discover how network dynamics in the brain subserves learning, consolidation and recall in tasks that requires memory of textures to solve. To do this we employ multichannel recordings (350 channel neuropixel probes) to record both single unit and local field potential activity across multiple brains structures simultaneously.


Ser Cymru II, Rising star fellowship (2018-2022) Mapping subicular mnemonic circuitry

BBSRC research grant, co-applicant (2020- 2023) Cortical pathways and synaptic mechanisms for texture discrimination learning in rodents

Research group

Team members:

Dr Jon Wilson (post-doc)

Dr Sungmin Kang (post-doc)

Harriet Hallum (Senior Technician)

Research collaborators

Dr Andrew Nelson

Prof. John Aggleton

Prof. Seralynne Vann

Prof. Rob Honey

Prof. Kevin Fox


Undergraduate education

Aberdeen, 1994-1998 BSc (Hons) Neuroscience

Postgraduate education

2002: MSc Neuroscience, University College London, thesis supervisor Dr Francis Edwards

2003-2007: D.Phil., Wolfson College, University of Oxford, Thesis: Reactivation of waking firing patterns during sleep. Supervisor: Dr. Jozsef Csicsvari


2018, Ser Cymru II Fellow, School of Psychology, Cardiff University

2011-2017 Post-doctoral researcher, Institute of Science and Technology (IST) Austria

2009 - 2011 Investigator Scientist, MRC Anatomical Neuropharmacology Unit, University of Oxford

2008 – 2009: CNRS post-doctoral researcher, Institut des Maladies Neurodégénératives, Université Bordeaux Segalen, France


Postgraduate research interests

If you are interested in applying for a PhD, or for further information  regarding my postgraduate research, please contact me directly (contact details available on the 'Overview' page), or submit a formal application.