Dr Alexa Morcom
Cognitive neuroscience of memory and ageing
People are able to recall unique events despite a vast number of overlapping experiences. We are interested in how these memories are stored and later selected for retrieval, and how these abilities evolve over the lifespan. We use fMRI, EEG brain imaging and behavioural methods in humans, combining traditional with multivariate and model-based analytic techniques such as machine learning and representational similarity analysis (see profile and publications here). I’m particularly keen to recruit PhD students with an interest in cognitive and brain ageing. Here are three project ideas.
Goal-driven memory retrieval in youth and/or ageing
How do people select which memories to retrieve, and shape retrieval to meet their needs? Mental control is important in young people as well as external cues [1] but older people may rely more on external cues [see 2]. You will have the opportunity to learn advanced EEG and/or fMRI brain imaging methods, apply them to tasks designed to assess memory and use them to test theories of memory or cognitive ageing. Possible projects may include collecting and analysing EEG data from young and older people as well as data analysis projects.
Mnemonic discrimination in ageing
Older people and those with early Alzheimer’s pathology find it difficult to remember precise details, likely reflecting loss of hippocampal and/or perirhinal integrity. We have developed a new database of 600 similar but confusable pairs of object images, and collected mnemonic discrimination data in young and older people alongside ratings of perceptual and conceptual image similarity. This project will use different models to test whether older people are biased to pattern completion rather than pattern separation [3].
Decline and compensation in the ageing brain
Even healthy ageing is associated with declines in memory and some other processes. But imaging has often shown striking activity increases as well as decreases in older adults during task performance. After 2 decades it remains controversial to what degree these results reveal compensatory changes [e.g. 4,5]. We have recently used a multivariate Bayesian approach showing that compensation may occur, although it is not the rule. You will combine this with a complementary approach to create stronger tests of the competing theories of neurocognitive ageing. This is a data analysis project so excellent data skills are a must.
Visit Alexa Morcom’s full profile for more information.