Separating forms of neglect using the Apples Test: validation and functional prediction in chronic and acute stroke.
Bickerton WL., Samson D., Williamson J., Humphreys GW.
OBJECTIVE: We report data on the validation and functional correlates of Apples Test, which attempts to differentiate between different forms of unilateral neglect. METHOD: Study 1 presents data from 25 participants with chronic brain lesions who completed the Apples Test and another standard measure of neglect (Star Cancellation). The patients' performance relative to 86 controls was assessed and their relative performance across the two tests compared. Study 2 recruited 115 acute hospital stroke patients who completed the Apples Test as part of the Birmingham University Cognitive Screen procedure. We assessed the relations between the different forms of neglect. Study 3 examined neglect type (as measured by the Apples Test) among the acute stroke group in relation to their activities of daily living abilities and affect. RESULTS: In Study 1 Apples Test scores correlated with Star Cancellation performance, while also differentiating between neglect across the page and neglect of parts of objects. Study 2 confirmed the dissociation from Study 1. "Pure" forms of each type of neglect were equally prevalent after right and left hemisphere lesions, while the presence of both deficits was associated with right hemisphere damage. Study 3 showed that each form of neglect also correlated with other measures of cognition. When compared with pure page-based neglect, object-centered neglect was associated with a lower Barthel score (p < .001), while patients with both forms of neglect had higher level of depression (p < .001) than those with the pure forms. CONCLUSIONS: We conclude that the Apples test provides a clinically applicable measure of different forms of neglect. In addition it is a useful predictor of functional outcome. We discuss the nature of the two forms of neglect diagnosed by the test and the functional implications.