ABSTRACT
Patients with severe visual neglect typically come to attention on a neurology ward because of their altered visual scanning behaviour. Eye deviations to the ipsilesional (i.e. intact) side of space and difficulty scanning towards the contralesional (i.e. neglected) side can be seen overtly, especially in the acute stages. Although the frequency of right and left neglect is controversial due to the confounding deficit of aphasia with left hemisphere damage (see Battersby, Bender, Pollock, & Kahn, 1956; De Renzi, 1982; Ogden, 1987; Zarit & Kahn, 1974), the greater severity of neglect with right hemisphere damage at least in the acute stages is well accepted (see De Renzi, 1982; Mesulam, 1981, 1983, 1985; Ogden, 1987; Roy et al., 1987). Acutely, patients with right hemisphere damage are more likely to deviate eyes, head and body towards their intact side than patients with left hemisphere damage. The overt manifestation of visual neglect clearly points to altered search of space. The major question we will address in this chapter is what cognitive mechanisms contribute to the overt scanning deficit?
