How to Assess Spatial Neglect - Line Bisection or Cancellation Tasks?

Abstract

Spatial neglect is usually assessed using cancellation tests or line bisection. A recent comparison of these tests has revealed a double dissociation, in which one neglect patient was impaired in line bisection but not in star cancellation whereas another showed the reverse deficit. This dissociation has prompted the question whether 'neglect' is still a meaningful theoretical entity. We compared line bisection and cancellation tasks regarding their accuracy in detecting spatial neglect. We tested 35 patients with well-defined spatial neglect using a line bisection task and four different cancellation tasks. The line bisection test missed 40% of our neglect patients. Far superior were the letter cancellation and bells tests, each of which missed only 6% of the cases. A deviation in line bisection is not fundamentally related to spatial neglect, but may also arise from other causes (e.g., hemianopia, or which hand is used), and therefore, should be treated with caution in clinical diagnosis. Cancellation tests, such as the bells test and letter cancellation, are more helpful tools to detect spatial neglect.

Estudo comparativo entre a relação do hemisfério acometido no acidente vascular encefálico e a evolução funcional em indivíduos destros

“…Most studies in the literature exclude these individuals because the test battery for hemineglect requires verbal responses. Th e star cancellation test was used because it is very sensitive to this kind of defi cit, it is the only test that can be applied to patients with left injuries who are unable to give verbal responses 33,36 and it does not depend on intact motor control of the dominant hand, since the stars can also be cancelled with the non-dominant hand.…”

Impaired perception of temporal order in auditory extinction

“…In addition, all patients had to fulfill the criterion (cf. [5]) in at least two of the following four tests. Letter cancellation [15]: the number of correct target letters on each half of the test sheet is n max = 30 on either side.…”

Visual hemispatial neglect, re-assessed

“…These paper-and-pencil tests are often standardized and are relatively easy to administer, requiring minimal equipment. For instance, line cancellation, line bisection, and visual search have played a major role in measuring and studying visual hemispatial neglect (a neurological disorder in which patients fail to attend to or make explicit use of contralesional information; e.g., Albert, 1973;Behrmann et al, 2004;Buxbaum et al, 2004;Ferber & Karnath, 2001;Halligan & Marshall, 1991). Although traditional paper-and-pencil tests are useful in assessing clinical signs, computerized testing can offer better control of stimulus parameters.…”