Hemispatial neglect

Overview

Hemispatial neglect, also known as unilateral neglect or spatial neglect, is a neuropsychological condition in which a person fails to attend to stimuli on one side of space, typically the left side, despite having no primary sensory or motor deficits. It most commonly occurs following a stroke or brain injury, particularly affecting the right hemisphere. Individuals with hemispatial neglect may ignore objects, people, or even parts of their own body on the affected side. This condition significantly impairs daily functioning and quality of life, especially if not properly recognized and managed.

Causes

Hemispatial neglect usually results from damage to areas of the brain involved in attention and spatial awareness. The most common causes include:

• Stroke: Particularly in the right parietal or frontal lobes, which are critical for spatial attention

• Traumatic brain injury (TBI): Damage to the right hemisphere can lead to neglect of the left side

• Brain tumors: If they affect regions responsible for spatial processing

• Neurodegenerative diseases: Less commonly, conditions like Alzheimer's disease can involve neglect-like symptoms

Right hemisphere lesions more frequently cause severe and persistent neglect than left-sided brain injuries.

Symptoms

Symptoms of hemispatial neglect can vary in severity and presentation, but typically include:

• Ignoring objects, people, or sounds on one side (usually the left)

• Eating food from only one side of the plate

• Failing to dress or groom one side of the body (e.g., shaving only half the face)

• Colliding with objects on the neglected side while walking or navigating

• Difficulty reading or writing, often omitting words or letters on the neglected side

• Lack of awareness or denial of the deficit (anosognosia)

The condition affects perception and attention rather than vision itself; the visual system is intact, but the brain fails to process input from the neglected side.

Diagnosis

Diagnosis of hemispatial neglect involves clinical observation and specialized neuropsychological testing. Common assessments include:

• Line bisection test: Patients are asked to mark the midpoint of a horizontal line; they often place the mark to the right of center

• Cancellation tests: Patients are asked to cross out target items on a page; they tend to miss items on the neglected side

• Drawing tasks: Patients may draw only half of a picture (e.g., a clock or a flower)

• Functional assessment: Observing behavior during activities of daily living (e.g., dressing, eating)

• Imaging: CT or MRI scans to identify the location and extent of brain injury

These tests help differentiate neglect from visual field deficits or other cognitive impairments.

Treatment

Treatment for hemispatial neglect is individualized and often requires a multidisciplinary approach. Key treatment strategies include:

• Occupational therapy: Focuses on compensatory strategies and retraining attention to the neglected side

• Visual scanning training: Encourages patients to actively scan toward the neglected side

• Prism adaptation therapy: Uses special lenses to shift visual input and promote spatial awareness

• Motor and sensory stimulation: Tactile or auditory cues may help increase awareness of the neglected side

• Cognitive rehabilitation: Exercises to improve attention and spatial processing

• Medication: In some cases, stimulants or antidepressants may be used to enhance attention and cognitive engagement

Early and consistent therapy is key to maximizing recovery and functional independence.

Prognosis

The prognosis of hemispatial neglect varies depending on the severity and location of the brain injury, as well as the timeliness and intensity of rehabilitation. Some individuals recover partially or fully over time, especially with early intervention, while others may experience persistent deficits that affect daily life. Severe neglect is associated with a poorer overall outcome and increased risk of disability. Ongoing therapy and caregiver support are often necessary to maintain functional gains and improve quality of life.