pRFs & Crowding in Amblyopia
Research type
Research Study
Full title
The Neural Basis of Visual Crowding in Strabismic Amblyopia
IRAS ID
215436
Contact name
John Greenwood
Contact email
Sponsor organisation
University College London
Duration of Study in the UK
1 years, 0 months, 1 days
Research summary
Amblyopia is the most common developmental disorder of vision, defined by impaired visual acuity in one eye despite optical correction. When associated with strabismus (ocular misalignment), central vision in the amblyopic eye is further impaired by crowding – objects that are otherwise visible in isolation become indistinguishable in clutter. Crowding is similarly elevated in the peripheral visual field of unaffected adults, which has been attributed to an enlargement of the receptive fields of neurons in the visual areas of the brain – the area of the visual field over which they are responsive. The aim of this study is to uncover the neural underpinnings of crowding in strabismic amblyopia, by investigating whether a similar relationship exists between crowding and estimates of receptive field size derived from neuroimaging. To achieve this, we will first measure acuity and crowding across the visual field in 10 adults with strabismic amblyopia and 10 controls with unaffected vision. Using functional magnetic resonance imaging (fMRI), we will then estimate population receptive field (pRF) sizes across the visual field and in a range of visual areas of the brain. If larger pRFs are associated with elevations in crowding, this will present the first evidence to suggest a common neural basis for amblyopic and peripheral crowding, thus advancing our understanding of strabismic amblyopia considerably.
REC name
East of England - Cambridge South Research Ethics Committee
REC reference
17/EE/0035
Date of REC Opinion
14 Feb 2017
REC opinion
Further Information Favourable Opinion