Is the Brixton Spatial Anticipation Test sensitive to frontal dysfunction? Evidence from patients with frontal and posterior lesions.

Introduction: The Brixton Spatial Anticipation Test is a widely used neuropsychological test, thought to assess executive functions and to be sensitive to frontal lobe lesions. Our aim was to investigate Brixton performance in patients with focal frontal or posterior lesions and healthy controls.

Method: We compared performance on the Brixton in a sample of 24 frontal patients, 18 posterior patients and 22 healthy controls. Both overall performance (total number of errors) and error types were analyzed.

Results: We found no significant differences between frontal and posterior patients and healthy controls in overall Brixton performance. Moreover, our error analysis showed no difference between frontal patients, posterior patients and healthy controls. The only exception was that posterior patients had a greater tendency to guess and make more errors when following specific rules than healthy controls but this was no longer significant once fluid intelligence was controlled for. We also found no significant difference between the performance of patients with left lateral ( = 11), right lateral ( = 10) or superior medial ( = 18) frontal lesions and healthy controls.

Conclusions: The Brixton test is not sensitive to frontal lobe dysfunction. It is likely that the test draws on a range of cognitive abilities not specific to frontal lobe lesions. Hence, caution should be taken when drawing conclusions about its neural substrates.