Movement perception
Animals move around to find food, shelter, and potential mates, and to avoid being eaten. Mobility brings with it the need to visually sense movement, whether to navigate safely through the world or to detect other mobile animals such as approaching predators. Specialised neurons in the visual system of the brain detect movement in the images received by the eyes. The outputs of these neurons are used to infer the character and cause of the movement. My research investigates how this complex neural processing supports our perception of visual movement, using experiments on human observers as well as computer simulations. Demonstrations of some of the moving images I and others have used to study human motion perception can be found on the Motion Demos section of the web site.
Perception of visual art
Artworks are among the most complex and diverse of human achievements. They can be studied from many different perspectives, including their cultural context, the personal and social history of the artist, the techniques and materials used, and so on. The perspective I use as a vision scientist is based on experimental psychology and neuroscience. Visual art is a product of the brain. It depends in particular on the immense mass of neurons the make up the visual system of the brain, the parts which respond to light entering the eye. Activity in these neurons mediates all of our conscious visual experiences, including those we have when making and viewing art. The visual system is arguably the most studied neural system in the brain. This scientific knowledge can be applied to help us to understand and appreciate certain aspects of visual art, supplementing rather than supplanting the insights of other, more traditional disciplinary perspectives.
In recent research work I have been particularly interested in using knowledge about the statistical properties of images to improve our understanding of visual art. The real-world images captured by eyes and cameras may seem hugely diverse, but in a statistical sense they are surprisingly predictable. The first digital cameras had a spatial resolution of 512x512 picture-elements (pixels), each of which could take on one of 256 lightness levels. Even such a rudimentary device had the capacity to capture an almost infinite variety of possible images (256 raised to the power of 512x512). However, the real-world images that would actually be captured by the camera are far from a random selection of these possible images. They would be a very selective sub-set of the possible images, because natural scenes are very consistent. The lightness values of neighbouring pixels do not vary randomly, but are often quite alike, because they arise from nearby points on natural surfaces and objects. The visual system can exploit this natural consistency to optimise the way that it processes images. The visual character of artworks should in turn be constrained by the processing strategies built into the visual system of artists and viewers. My research searches for the tell-tale signs of visual processing in the statistical properties of artworks.
Further details of this research, including the computer algorithms I use to analyse images, can be found in my publications and in my project pages at the Open Science Framework.
I recently published a book about the psychology of art that draws connections between scientific knowledge about how and why humans engage in art-making so enthusiastically (brain science, evolution, the psychology of perception), and the views of artists and art historians about the artistic process (theories and movements in art history). It covers such topics as the depiction of space, movement and colour, traditional and modern concepts of great art, and the impact of fakery, reproduction technology, and sexism on judgements about art.
I have also created a website to support the book, which contains a full list of all the book's references, suggestions for further readings, and links to online copies where available.
An exclusive full chapter from the book is available online in the British Psychological Society’s journal The Psychologist.
The book's publisher also has a special offer for purchasers of the book, giving 20% off. Use code BSB20 at check-out.
Funding
Leverhulme Emeritus Fellowship (2024-2026)
The Moving Pupil of the Eye and Visual Illusions of Motion
£12,401
ESRC Research Grant (2013-2016)
The Influence Of The Human Form On Visual Judgements Of Movement
£286,945
Wellcome Trust Research Grant (2008-2011)
Computational and psychophysical studies of polarity effects in human visual motion processing
£126,654
EPSRC Network Grant (2004-2005)
Network: Art and Science of Motion Perception
£15,259.
Wellcome Trust Research Grant (2000-2003)
Integrating models of motion analysis in the human visual system.
£116,520
EPSRC Research Grant (1997-2000)
The use of image blur as a depth cue in human vision.
£137,017
EPSRC Research Grant (1993-1996)
Psychophysical studies of interactions between first-order and second-order motion stimuli.
£98,565
MRC Project Grant (1991-1993)
Temporal properties of low-level motion processes in human vision.
£46,155
SERC Research Grant (1990-1993)
Perceptual studies of high level motion processing in the human visual system.
£58,477
SERC Research Grant (1988-1991)
Psychophysical studies of the aperture problem in motion processing.
£47,707
MRC Project Grant (1985-1988)
Spatial and temporal primitives involved in early processing of visual motion.
£12,756