Professor Colin Clifford

Functional Imaging of Human Visual Cortex

Functional magnetic resonance imaging (fMRI) provides us with an overview of the functional organization of the human visual system, allowing us to examine visual processing throughout the cortical hierarchy.

Goddard, E., Mannion, D.J., McDonald, J.S., Solomon, S.G. & Clifford, C.W.G. (2011) Colour preference argues against a dorsal component of human V4, Journal of Vision 11(4): 3, 1–21.

Perception of Bistable Images

When viewing binocularly rivalrous stimuli or ambiguous structure-from-motion, perception alternates between two very different interpretations of the sensory input even though the visual stimulus remains constant. This affords the experimenter a means of investigating the content of subjective perceptual awareness dissociated from the sensory input.

Clifford, C.W.G. (2009) Binocular rivalry, Current Biology, 19, R1022-R1023.

Touch

Although vision is our dominant sense, much can be learnt about sensory coding from the the study of touch and its interaction with vision.

Arabzadeh, E., Clifford, C.W.G. & Harris, J.A. (2008) Vision merges with touch in a purely tactile discrimination, Psychological Science, 19, 635-641.

Visual Motion Processing

The ability to see motion is ubiquitous in the animal kingdom and, next to the detection of light and dark, may be the oldest and most basic of visual capabilities.

Maloney, R.T., Watson, T.L. & Clifford, C.W.G. (2014). Determinants of motion response anisotropies in human early visual cortex: the role of configuration and eccentricity, Neuroimage, 100, 564-579.

Contextual Modulation in Vision

Contextual modulation refers to the sometimes profound effects of surrounding or preceding image structure on the perception of attributes of a visual scene. We are particularly keen to understand the function of these modulatory interactions.

Clifford, C.W.G. (2014). The Tilt Illusion: Phenomenology and Functional Implications, Vision Research, 104, 3-11.

Visual Feature Binding

The question of how distributed neural processing gives rise to a unified perceptual representation of the world is often termed The Binding Problem. We aim to elucidate the mechanisms of binding in human vision through psychophysics and neuroimaging.

Clifford, C.W.G. (2010). Dynamics of visual feature binding, in Space & Time in Perception & Action, R. Nijhawan & B. Khurana (eds.), Cambridge University Press, pp.199-215.

Gaze & Face Perception

The dissonance we experience while looking at this image indicates that we have strong expectations about the basic structural properties of a face that cannot help but influence our perception. We have recently investigated this issue in the context of gaze perception.

Mareschal, I., Calder, A.J. & Clifford, C.W.G. (2013) Humans have an expectation that gaze is directed towards them, Current Biology 23, 717-721.