The dynamics of information representation during working memory - WCUB, ENWW

Lead Research Organisation: University of Oxford
Department Name: Interdisciplinary Bioscience DTP

Abstract

Our senses capture information about the outside world, certain brain areas then transform this information and again serve it to different brain areas generating behavior. Behavior can be explained by failure or success at each of this processing stages. My thesis focuses on the second step, specifically, how and where the brain transforms information into a format that is 'readable' for brain areas that generate decisions, leading to observable behavior. I will address this problem in the frame of working memory, an active form of short term memory. Typically, a working memory task entails remembering certain objects and rules over short timescales (seconds) and then make a decision about a related, new object according to the current rule. Using machine learning algorithms, information about task variables such as color, location or rule can be decoded from the neuronal activity in certain brain regions, specifically the prefrontal cortex, while the human or animal is doing a working memory task. This allows us to track changes in the representation of relevant information i.e. observing the transformation of information leading to correct or erroneous behavior. I will analyze electrophysiological recordings from of non-human primates to investigate these questions on the level of single or small populations of neurons. Furthermore, I will collect and analyze intracranial electro-encephalography recordings from epilepsy patients bridging the translational gap between animal and human experiments. This will be complemented by a magneto-encephalography study with
healthy human subjects. Together, I hope this data will give answers on how the representation of information changes across brain regions and how this relates to behavior.

BBSRC priority and proposed research addresses
Brain Science and Mental Health
Systems approaches to the biosciences

Publications

10 25 50

Studentship Projects

Project Reference Relationship Related To Start End Student Name
BB/M011224/1 01/10/2015 31/03/2024
1810149 Studentship BB/M011224/1 01/10/2015 30/09/2019
 
Description Working memory (WM) is characterized by the ability to maintain stable representations over time; however, neural activity associated with WM maintenance can be highly dynamic. We explore whether complex population coding dynamics during WM relate to the intrinsic temporal properties of single neurons in lateral prefrontal cortex (lPFC), the frontal eye fields (FEF) and lateral intraparietal cortex (LIP) of two monkeys (Macaca mulatta). We found that cells with short timescales carried memory information relatively early during memory encoding in lPFC; whereas long timescale cells played a greater role later during processing, dominating coding in the delay period. We also observed a link between functional connectivity at rest and intrinsic timescale in FEF and LIP. Our results indicate that individual differences in the temporal processing capacity predicts complex neuronal dynamics during WM; ranging from rapid dynamic encoding of stimuli to slower, but stable, maintenance of mnemonic information.
Exploitation Route Advancing our understanding of basic brain function
Sectors Other

URL https://www.biorxiv.org/content/early/2017/12/14/233171
 
Description Collaboration for the exchange of experimentally collected data for theoretical analysis 
Organisation Massachusetts Institute of Technology
Country United States 
Sector Academic/University 
PI Contribution Provided data
Collaborator Contribution Provided data
Impact This collaboration has led to a preprint: https://www.biorxiv.org/content/early/2017/12/14/233171. It is not interdisciplinary.
Start Year 2016