Hemispatialer

Hemispatialer is a neuropsychological syndrome characterized by diminished awareness of stimuli on the side of space opposite a brain lesion. It most commonly follows unilateral damage to the right hemisphere, leading to left-sided neglect, but can occur after left-hemisphere injury producing right-sided neglect. The condition can affect personal space (the body), peripersonal space (within reach), and extrapersonal space (the broader environment), and symptoms may manifest across visual, auditory, and tactile modalities.

Causes include stroke (ischemic or hemorrhagic), traumatic brain injury, brain tumor, or infection. Neuroanatomically, hemispatialer is associated with disruption of attention networks involving the parietal and temporal cortices, especially the right inferior parietal lobule and temporoparietal junction, and their connections to frontal oculomotor and dorsal attention systems. The syndrome often coexists with anosognosia and extinction, where patients fail to respond to contralesional stimuli when competing stimuli are present.

Clinical features and assessment: patients may ignore objects or their own left side, fail to dress the left side of the body, fail to acknowledge people or sounds from the left, or fail to bisect lines accurately. Clinicians use neglect-specific tasks such as line bisection, cancellation tests, and functional observational scales, along with imaging to identify the lesion.

Management and prognosis: rehabilitation emphasizes systematic visual exploration, cueing and scanning strategies, prism adaptation therapy, and limb activation. Noninvasive brain stimulation and pharmacotherapy have been explored, with variable results. Recovery varies; many patients improve in weeks to months, but some deficits persist, especially after dominant or large lesions.