Mechanisms underlying memory and decision making in health and disease

  • Research type

    Research Study

  • Full title

    Mechanisms underlying memory and decision making in health and disease

  • IRAS ID

    241280

  • Contact name

    Masud Husain

  • Contact email

    masud.husain@ndcn.ox.ac.uk

  • Sponsor organisation

    University of Oxford

  • Duration of Study in the UK

    4 years, 0 months, 1 days

  • Research summary

    The aim of this study is to provide an improved understanding of the brain mechanisms underpinning how memory affects decision making, both in health and in neurological diseases. The hippocampus is known to play a crucial role in memory. Furthermore, it has been demonstrated that hippocampal activity recorded from specialised cells is periodically ‘replayed’ and it is proposed that replay may play an important role in linking memory to choice during decision making. Interestingly, recent studies reveal that replay is at least partially mediated by the release of the neurotransmitter, dopamine.

    Dopamine is known to play a crucial role in mediating normal behaviours. It is well known that patients with Parkinson’s Disease (PD), who lack sufficient quantities of endogenous dopamine, can suffer from a range of disorders of goal directed behaviour – with often disabling consequences. For example, some patients with PD are poorly motivated to engage in action for reward (a condition known as apathy). The precise neural mechanisms linking a lack of endogenous dopamine to apathy in PD remain poorly understood.

    In this study we seek support for the hypothesis that poor motivation to seek rewards (or apathy) in PD manifests as a reduction in occurrence of replay during decision making. Furthermore, we predict that exogenous dopamine replacement reinstates reward sensitivity and the occurrence of replay. We will test these hypotheses by performing magnetoencephalographic (MEG) recordings whilst participants perform decision making tasks.

    We will also study patients with diseases known to result in hippocampal damage and healthy age matched controls. We predict that replay relies on intact hippocampal function and is impaired in patients with diseases that result in hippocampal damage.

    The study will take place at the University of Oxford and is fully funded by the Wellcome Trust. We plant to recruit 108 patients over four years.

  • REC name

    South Central - Oxford C Research Ethics Committee

  • REC reference

    18/SC/0560

  • Date of REC Opinion

    2 Nov 2018

  • REC opinion

    Favourable Opinion