Progress and neglect

Abstract

The explosion of interest in neuropsychology has come about because the effects of brain injury can sometimes provide compelling tests of psychological theories, and the symbiotic relation between models of normal and disordered performance is now widely acknowledged. Unilateral neglect is of especial interest because it presents a challenge to theories couched exclusively in terms of cognitive psychology, which seldom take the left-right dimension into account. Moreover, severe neglect is most commonly left-sided, and even those cognitive theories that do incorporate the left-right dimension give no convincing reasons as to why this should be. Almost certainly, the answer is to be found in some feature(s) of brain organisation, though exactly which remains unclear. Importantly, though, the first lesson of neglect is therefore that an adequate theory of spatial abilities will need to relate more directly to neural mechanisms than would seem to be necessary in some other domains (e.g. language). This point is underscored by the remarkable findings of remission of neglect after caloric stimulation (Perani et al., 1993; Rubens, 1985).