Visual impairment is a global and potentially devastating affliction. Sensory substitution
devices have the potential to lessen the impact of blindness by presenting vision via another
modality. The chief motivation behind each of the chapters that follow is the production of
more useful sensory substitution devices. The first empirical chapter (chapter two)
demonstrates the use of interactive genetic algorithms to determine an optimal set of
parameters for a sensory substitution device based on an auditory encoding of vision (“the
vOICe”). In doing so, it introduces the first version of a novel sensory substitution device which
is configurable at run-time. It also presents data from three interactive genetic algorithm
based experiments that use this new sensory substitution device. Chapter three radically
expands on this theme by introducing a general purpose, modular framework for developing
visual-to-auditory sensory substitution devices (“Polyglot”). This framework is the fuller
realisation of the Polyglot device introduced in the first chapter and is based on the principle
of End-User Development (EUD). In chapter four, a novel method of evaluating sensory
substitution devices using eye-tracking is introduced. The data shows both that the copresentation
of visual stimuli assists localisation and that gaze predicted an auditory target
location more reliably than the behavioural responses. Chapter five explores the relationship
between sensory substitution devices and other tools that are used to acquire real-time
sensory information (“sensory tools”). This taxonomy unites a range of technology from
telescopes and cochlear implants to attempts to create a magnetic sense that can guide
further research. Finally, in chapter six, the possibility of representing colour through sound is
explored. The existence of a crossmodal correspondence between (equi-luminant) hue and
pitch is documented that may reflect a relationship between pitch and the geometry of visible
colour space
