Ipsilateral neglect from a subcortical lesion: effects of spatial position, distractors, and repeated trials

This report describes a patient with right putaminal hemorrhage who showed ipsilateral (right-sided) neglect.

Although lesions to subcortical regions may result in contralateral hemispatial neglect, ipsilateral neglect from putaminal damage has not been reported. It has been posited that ipsilateral neglect from unilateral frontal lesions may be induced by a contralateral attentional grasp. This patient's putaminal hemorrhage may have induced frontal dysfunction with an attentional grasp.

Because distracting stimuli, as well as close (vs. far) spatial position, may alter an attentional grasp and because fatigue may compromise the ability to disengage, we tested the patient with repeated trials of line bisection in peripersonal (close) and extrapersonal (far) space with left-sided, right-sided, and both-sided distractors.

The patient's leftward bias increased with repeated trials, particularly with those in the close condition and with left-sided distractors.

Right putaminal hemorrhage may produce ipsilateral neglect. Our patient's putaminal-white matter injury may have induced frontal dysfunction, and, with repeated trials, his right basal ganglia-frontal network may have fatigued. This fatigue, together with left-sided distractors in the close condition, seemed to increase his contralateral attentional grasp.