49

The unilateral clinical signs described after interhemispheric disconnection syndrome are generally related to cognitive functions underpinned by the left hemisphere (language, writing, reading, etc.). As part of a treatment program following damage to the corpus callosum, we proposed a haptic line bisection test (by touch) performed with the left and right hands to a patient with poor command of French. In this patient, we observed an average deviation percentage of 0.3 % in the left-hand test and 15.5 % in the right-hand test, suggesting left unilateral spatial neglect. We compared these scores with those of 8 control subjects. Statistical analysis showed a significant difference between the patient’s score and those of the controls for the right-hand test (p=0.002), but not for the left-hand test (p=0.46). This initial observation suggests that left unilateral spatial neglect of the right hand under haptic conditions could be a clinical sign of interhemispheric disconnection.