Sanjay Manohar’s Lab – Clinical Motivation Research

Motivation is our ability to perform better when we are incentivised. It allows us to break through our natural performance limits, by energising action, boosting attention and improving precision.

My aim is to model motivation, using the idea of “costly noise-reduction”. According to this model, signal-to-noise ratio in the brain can be increased, but this is expensive. The cost is two-fold: opportunity cost, and energetic cost. Read more: Reward pays the cost of noise reduction in cognitive and motor control, Manohar et al. Current Biology 2015,

Vacancy

I am looking for a graduate research assistant to join the lab. Applications will open in Oct 2017.  The successful applicant will work in the Nuffield Department of Clinical Neuroscience, with strong collaborations in Experimental Psychology, FMRIB and OHBA. Opportunities include drug manipulations, study of patients taking dopaminergic and cholinergic medications, functional imaging and MEG. Applicants should ideally have a degree in a psychology, neuroscience, computational, psychiatric, neurological or related discipline, and should be interested in pursuing an academic career.

 Video papers

Two types of motivation

We ought to perform better when rewards are dependent upon our performance. But studies of motivation implicate dopamine, a transmitter that signals rewards irrespective of whether they are contingent on our actions. By directly comparing contingent rewards and guaranteed rewards, we find two distinct contributions to motivation. I plan to examine whether dopamine is  specifically needed to signal reward effects, or whether it plays a role in performance-contingent outcomes (when reward is factored out).

Read more: Distinct motivational effects of contingent and non-contingent rewards, Manohar et al. Psychological Science 2017 (in press)

Apathy in Parkinson’s disease reflected in pupil dilatation

Before an action is performed, pupil diameter indicates the level of motivation for performing that action. We manipulated motivation by offering different incentives to people before they made eye movements to a target. Parkinson’s disease patients with apathy showed blunted pupil responses, coupled with a  reduced motivational improvement. This effect was modulated by dopaminergic drugs.

Read more: Reward sensitivity deficits modulated by dopamine are associated with apathy in Parkinson’s disease, Muhammed et al. Brain 2016

Current and Previous Lab Members and Students

  • Joyce Vromen 2017 (Postdoc) Motivation in health and neurological disease
  • Tara Keenan 2016-2017 (Undergrad) Does motivation attenuate perceptual noise?
  • Daniel Xu 2016-2017 (Undergrad) The way we remember things modulates reinforcement learning
  • Dawn Finzi 2015-2016 (Masters) Motivation by contingent and non-contingent rewards
  • Sooraj Mahesh 2015-2016 (Undergrad) Measuring model-based learning independently of working memory
  • Stephanie Hirschbichler (PhD) 2016- Mechanisms of motivation in the oculomotor system
  • Anna Sadnicka 2015 (PhD) Altered perception of millisecond time intervals in dystonia

Collaborators

  • Masud Husain neurology of impulsivity, apathy and memory
  • Zargol Moradi social cognition in brain disorders
  • Patricia Lockwood social cognition and psychopathy
  • Tim Vogels computational models of memory
  • Sean J Fallon dopamine in working memory
  • Matthew Apps computational models of fatigue and social cognition
  • Steve Kennerley (UCL) neurophysiology of the frontal lobe
  • Parashkev Nachev (UCL) neurologist and general genius
  • Kailash Bhatia (UCL) Dopamine, movement disorders and eye movements
  • Paul Bays (Cambrige) working memory and motor control

 

Publications