Hemispatial Neglect: Understanding and Rehabilitating this Neurological Disorder
A little-known spatial attention disorder affecting thousands of patients after a Stroke
Hemispatial neglect, also known as unilateral spatial neglect, is a fascinating and complex neurological disorder that typically occurs after a brain injury, particularly a stroke. Affected individuals seem to completely ignore one side of their visual space, most often the left side. Unlike blindness, their eyes function perfectly: it is their brain that no longer processes information from one visual hemifield.
What is Hemispatial Neglect?
Hemispatial neglect is a deficit in spatial attention characterized by an inability to detect, respond to, or orient towards stimuli presented on the side opposite the brain lesion. In about 80% of cases, it is the right hemisphere that is affected, leading to neglect of the left space.
This disorder goes far beyond a simple visual problem. It affects the mental representation of space: patients neglect not only what they see but also what they imagine. If you ask them to draw a clock from memory, they will place all the numbers on the right half of the dial, completely forgetting that numbers 7 to 11 should be on the left.
Symptoms of Hemispatial Neglect
The manifestations of hemispatial neglect are varied and can significantly impact daily life. Here are the most characteristic signs that family members and caregivers should be aware of.
🍽️ In Daily Life
The patient only eats the food located on the right half of their plate, completely ignoring the other half. They may turn their plate to access the "missing" food, without realizing that they are systematically neglecting the same side.
🚶 When Moving
While walking, the person consistently bumps into obstacles on their left (door frames, furniture, other people) as if they do not exist. In a wheelchair, they roll into walls on the neglected side.
👔 When Dressing
The patient dresses only on one side, forgetting to put their left arm through the sleeve or button the left side of their shirt. They may also neglect to shave or apply makeup on the left half of their face.
📖 When Reading
The patient starts reading in the middle of the line, systematically skipping the first words on the left. They may also neglect the entire left column of a two-column text.
✍️ When Writing or Drawing
Drawings are compressed on the right half of the page, leaving the left side empty. A drawn clock will have all the numbers crammed on the right. Writing may start in the center of the page.
⚠️ Anosognosia: When the Patient Denies Their Disorder
A particularly troubling phenomenon often accompanies hemispatial neglect: anosognosia. The patient is completely unaware of their deficit. If you point out that they have forgotten half of their plate, they may categorically deny it or find rational justifications ("I'm not hungry anymore," "This dish doesn't look good"). This lack of awareness of the disorder significantly complicates rehabilitation, as the patient does not understand why they are being subjected to exercises.
The Neurological Causes of Hemispatial Neglect
Hemispatial neglect results from a lesion in the right cerebral hemisphere, more specifically in regions involved in spatial attention. The structures most frequently affected are the posterior parietal cortex, the superior temporal cortex, and the frontal cortex.
Why Mainly the Right Hemisphere?
The functional asymmetry of the brain explains why left hemispatial neglect is much more common and severe than right hemispatial neglect. The right hemisphere processes the entire visual space (left and right), while the left hemisphere primarily focuses on the right space.
Thus, when the right hemisphere is damaged, the intact left hemisphere can only partially compensate, leaving the left space neglected. Conversely, a lesion in the left hemisphere is better compensated by the right hemisphere, which already processes the entire space.
🧠 The main causes of hemispatial neglect
- Stroke: the most common cause, responsible for 80% of cases
- Traumatic brain injury: following a road accident or a fall
- Brain tumor: compressing the parietal or temporal regions
- Intracranial hemorrhage: affecting attentional areas
- Encephalitis or brain infections: more rarely
Diagnosis of hemispatial neglect
The diagnosis of hemispatial neglect is based on a battery of standardized neuropsychological tests administered by neuropsychologists and occupational therapists at the patient's bedside or in consultation.
Main clinical tests
The cancellation test: The patient is presented with a sheet containing dozens of small lines arranged randomly. Their task is to cross out all the lines. A patient with hemispatial neglect only crosses out the lines on the right, completely ignoring those on the left, even when their attention is drawn to the neglected area.
The line bisection test: The patient must mark the middle of horizontal lines of different lengths. People with hemispatial neglect systematically shift their mark to the right, as if the left part of the line does not exist.
The drawing copy test: The patient is asked to copy a complex figure (a house, a clock, a flower). The produced drawing contains only the right half of the elements, sometimes with attempts at compensation where all the details are compressed on one side.
The reading test: It is observed whether the patient starts reading in the middle of the lines or systematically omits the first words on the left.
💡 Simple test to do at home
If you suspect hemispatial neglect in a loved one after a stroke, ask them to draw a clock with all the numbers. Hemispatial neglect will be revealed by all the numbers clustered on the right half of the dial. Consult a neurologist quickly if you observe this sign.
Rehabilitation of hemispatial neglect
The rehabilitation of hemispatial neglect is a progressive process that involves various health professionals: neuropsychologists, occupational therapists, speech therapists, and physiotherapists. The goal is to help the patient become aware of their neglected environment and develop compensatory strategies.
Scientifically validated rehabilitation techniques
🔍 Systematic visual scanning
The patient is taught to methodically explore the space from right to left, using visual cues. For example, when reading, a red line is placed to the left of each line to indicate the starting point. Gradually, the patient integrates this scanning movement into their habits.
💫 Optokinetic stimulation
Moving visual stimuli pass from right to left in front of the patient's eyes, encouraging their gaze to naturally follow towards the neglected side. This technique improves visual exploration of the left space.
🎯 Prism adaptation
The patient wears prism glasses that shift their visual field to the right. As they adapt to this shift, their brain gradually recalibrates their representation of space. After removing the glasses, the improvement persists for several hours, even days with regular practice.
🖐️ Vibrotactile stimulation
Vibrations applied to the muscles of the neck on the left side (opposite to the lesion) activate spatial orientation systems and temporarily reduce neglect. This technique can be combined with visual scanning exercises.
🪞 Mirror therapy
A mirror is placed vertically in the patient's sagittal plane. The reflection of their right side fills their left visual field, creating the illusion of a complete body. This technique helps restore body and spatial representation.
✨ Practical exercises for daily life
- Deliberately place important objects (phone, glass of water) on the left side
- Encourage the patient to turn their head to the left before any action
- Use color cues (red tape) on the left edge of documents
- Ask the patient to count aloud the objects starting from the left
- Practice visual search games (like "Where's Waldo?") emphasizing left exploration
- During meals, rotate the plate after each bite to force exploration
- Encourage bilateral activities: sorting objects with both hands simultaneously
- Use a metronome or sound signal on the left to attract attention
The crucial role of loved ones
The entourage plays a fundamental role in the rehabilitation of hemispatial neglect. It is essential that loved ones understand that the patient is not intentionally ignoring what is on their left: they are literally unaware of it. Positioning themselves systematically on the patient's right to communicate may seem practical, but it actually reinforces the deficit.
On the contrary, loved ones should deliberately position themselves on the left side, use auditory or tactile stimulations on that side, and constantly encourage the patient to explore the neglected space. This repeated solicitation promotes brain plasticity and accelerates recovery.
"My husband had severe left-sided neglect after his Stroke. The first few days were confusing: he ate half of his plate and claimed to have finished everything. Thanks to the hard work of the occupational therapist and daily exercises at home, he gradually regained awareness of his left side. Six months later, he can read again and move around safely. Rehabilitation requires patience and perseverance, but progress is real."
SCARLETT: cognitive rehabilitation after a Stroke
The SCARLETT program from DYNSEO offers cognitive exercises tailored for patients in neurological rehabilitation. Visual attention games, spatial scanning, and memory exercises are specifically designed to stimulate cognitive functions impaired after a Stroke. The intuitive interface allows for independent or assisted use, with progress statistics to track development.
Discover SCARLETTEvolution and prognosis
Left-sided neglect generally evolves favorably with intensive and early rehabilitation. In about 50% of cases, significant recovery is observed in the first three months following the Stroke. However, about 20% of patients retain chronic left-sided neglect that requires permanent adaptations to their environment.
Factors indicating a good prognosis include: early rehabilitative care (in the first weeks), absence of anosognosia or its rapid resolution, patient motivation, active support from family, and preservation of other cognitive functions (memory, language, executive functions).
Intensive rehabilitation
45 minutes to 1 hour per day of specific exercises significantly accelerates recovery
Multimodal approach
Combining several techniques (prisms, stimulations, exercises) optimizes results
Family involvement
Daily support from loved ones doubles the chances of complete recovery
Digital tools
Cognitive rehabilitation apps allow for fun and motivating daily practice
Environmental adaptations
In addition to rehabilitation, adapting the patient's environment facilitates daily life and secures their movements. These adjustments should not replace rehabilitation efforts but intelligently accompany them.
🏠 Recommended home adaptations
- Install bright colored strips on the left edge of doors and hallways
- Strategically place mirrors to widen the field of vision
- Clear the space to the left of any obstacles to prevent falls
- Use plates with colored compartments to facilitate meals
- Place visual markers (stickers, arrows) pointing left in each room
- Prefer uniform lighting without shadow areas that accentuate neglect
Left-sided neglect and driving
The question of resuming driving is crucial for many patients. Left-sided neglect is a formal contraindication to driving as long as it persists significantly. The risk of accidents is multiplied by five due to the inability to detect dangers (pedestrians, vehicles, signs) located on the left.
An evaluation by an occupational therapist specialized in driving is essential before resuming the wheel. This evaluation includes tests in a simulator and then in real situations, on the road. Even if the neglect has partially resolved, vehicle adaptations (wide-angle mirrors, side cameras, blind spot alerts) may be necessary.
Left-sided neglect: an invisible but real disorder
Left-sided neglect remains unknown to the general public, yet it affects thousands of people every year. This complex neurological disorder profoundly disrupts the daily lives of patients and their loved ones. Contrary to what one might think, it is not a simple visual problem, but an alteration of the mental representation of space.
The good news is that with intensive and early rehabilitation, combining different therapeutic approaches, significant improvement is possible in the majority of cases. The active involvement of loved ones, the use of suitable digital tools, and the perseverance of the patient are the keys to optimal recovery.
If you or a loved one are affected by left-sided neglect, do not hesitate to quickly consult a specialized neurorehabilitation team. Every day counts in the recovery process, and advances in neuroscience today offer encouraging therapeutic prospects.