Visual Illusions Group

The Visual Illusions group is made up of Ben, Alexandra, and Charlotte.

Ben Brown

I am a PhD student investigating face perception at UCL’s Vision Lab. I completed my Psychology degree at Sussex in 2009, before detouring temporarily into commercial software development. I’ve also worked with children with communication, sensorimotor and learning difficulties across care and educational settings.

I’m interested in how we process complex sensory information, particularly dynamic “streams” such as from motion. My research focuses on the encoding of time-varying facial expressions, which are subtle and fleeting yet highly socially relevant.

Perception science is often best approached from two angles, so that computational modelling (“how might facial expressions be efficiently represented?”) informs human experiments (“Is this what happens in the brain?”). By decomposing the variance present in naturalistic videos of faces, I hope to generate predictions amenable to psychophysics and brain imaging.

Alexandra Kalpadakis Smith
Alexandra Kalpadakis Smith

I am currently a Cognitive Neuroscience research student investigating ‘visual crowding’ at UCL’s Vision Research Lab. Crowding is the curious phenomenon where an object that is readily identified in isolation, becomes unrecognisable when found in clutter; it is present in both ‘normal’ peripheral vision and the central vision of children with amblyopia. Using behavioural psychophysics, I am investigating crowding in the context of face perception, with the aim of gaining a better understanding of the processes involved in the recognition of objects in general, and faces in particular.

I also have an active interest in visual aesthetics and the development of new, objective measures for the study of aesthetic preference. My previous work has focused on the iconic abstract paintings of the Dutch artist Piet Mondrian (1872-1944), attempting to capture their underlying compositional principles, using Interactive Evolutionary Computation with eye movements as a fitness measure.

Charlotte Harris
Charlotte Harrison

I am currently a PhD student at UCL’s Vision Lab investigating the temporal dynamics of gaze perception. Prior to my PhD I completed a BSc in Psychology at Royal Holloway, University of London, where I also worked as a research assistant at the CUBIC MRI Unit. Following this I completed an MSc in Neuroscience at the Institute of Psychiatry, where I specialised in functional neuroimaging and tractography.

Social interactions are inherently dynamic and how long a person looks is at least as important as where they are looking. Using psychophysical experiments and eye-tracking, my research aims to investigate how we perceive the duration of gaze, with a particular focus on mutual gaze. The overall objectives of my thesis are to establish a) what constitutes a comfortable length of mutual gaze, b) whether humans have the ability to precisely time gaze duration, to complement the already documented high sensitivity to gaze direction, and c) to what extent mechanisms for perception of gaze duration are specialised and independent of timing mechanisms for other visual events.