Summary about Disease
Unilateral neglect (also called hemispatial neglect, spatial neglect, or neglect syndrome) is a neuropsychological condition that occurs after brain damage, typically to the right parietal lobe. It results in a deficit in attention to and awareness of one side of space, usually the side opposite the brain damage (contralateral). This means a person with unilateral neglect may fail to attend to or acknowledge stimuli presented on the left side of their body and the space around them, even though their sensory abilities (vision, hearing, touch) are intact. It is important to note that unilateral neglect is a disorder of attention, not of sensory function.
Symptoms
Symptoms of unilateral neglect can vary widely in severity and presentation. Common symptoms include:
Failure to report or respond to stimuli on one side of the body or in the environment: This may involve ignoring objects, people, or sounds on the affected side.
Inability to dress or groom one side of the body: For instance, shaving only one side of the face or applying makeup to only one side.
Eating food only from one side of the plate: Leaving food untouched on the neglected side.
Difficulty navigating the environment: Bumping into objects or turning only in one direction.
Reading only one side of a page: Missing words or sentences on the neglected side.
Denial or lack of awareness of the deficit: Anosognosia is a common symptom in unilateral neglect, where the individual is unaware of their condition or its severity.
Extinction: When presented with stimuli on both sides simultaneously, the stimulus on the affected side is ignored. However, the patient may detect the stimuli on the affected side if it's presented alone.
Motor neglect: Decreased use of a limb on the side opposite the brain lesion, even when motor strength is intact.
Causes
The most common cause of unilateral neglect is stroke, particularly stroke affecting the right parietal lobe. Other causes include:
Traumatic brain injury (TBI)
Brain tumors
Brain infections
Neurodegenerative diseases Damage to the right parietal lobe is most often associated with left-sided neglect. Damage to the left parietal lobe can result in right-sided neglect, but it is less common and often less severe.
Medicine Used
There is no specific medication to directly treat unilateral neglect. Treatment focuses on rehabilitation and compensatory strategies. However, some medications have been studied and may be used to improve attention and arousal:
Dopaminergic medications: Some studies suggest that medications that enhance dopamine levels may improve attention and awareness in individuals with unilateral neglect.
Cholinesterase inhibitors: These medications, typically used for Alzheimer's disease, may improve attention and cognitive function in some cases. The use of any medication is determined on a case-by-case basis by a physician and in conjunction with occupational and physical therapy.
Is Communicable
Unilateral neglect is not communicable. It is a neurological condition caused by brain damage and is not infectious or contagious.
Precautions
Precautions for individuals with unilateral neglect involve:
Environmental modifications: Arranging the environment to compensate for the neglect. For example, placing important items on the non-neglected side.
Safety measures: Being mindful of the neglected side to prevent accidents, such as falls or collisions.
Awareness training: Helping the person become more aware of their neglect and develop strategies to attend to the neglected side.
Assistive devices: Using assistive devices, such as prism glasses, to expand the visual field.
Caregiver education: Educating caregivers about the condition and strategies to support the individual.
How long does an outbreak last?
Unilateral neglect is not an "outbreak" like an infectious disease. It is a chronic condition resulting from brain damage. The duration of symptoms can vary significantly depending on the severity of the brain injury, the individual's response to rehabilitation, and the presence of other cognitive impairments. Some individuals may experience spontaneous recovery in the initial weeks or months after the brain injury. However, some level of neglect may persist long-term.
How is it diagnosed?
Unilateral neglect is diagnosed through a combination of clinical observation and neuropsychological testing. Diagnostic methods include:
Clinical observation: Observing the individual's behavior and performance in everyday activities.
Cancellation tasks: The patient is given a sheet of paper with multiple identical stimuli (e.g., lines or shapes) and asked to cross out all of them. Individuals with neglect typically fail to cross out stimuli on the affected side.
Line bisection tasks: The patient is asked to bisect a horizontal line. Individuals with neglect often bisect the line off-center, toward the non-neglected side.
Drawing tasks: The patient is asked to copy a drawing or draw from memory. Individuals with neglect may omit details or entire sections on the neglected side.
Behavioral Inattention Test (BIT): A standardized test battery that assesses neglect in both near and far space, and in everyday activities.
Neuroimaging: MRI or CT scans of the brain are used to identify the location and extent of the brain lesion.
Timeline of Symptoms
The onset of unilateral neglect is typically sudden, coinciding with the event that caused the brain damage (e.g., stroke or TBI).
Acute phase (days to weeks): Symptoms are most severe and may include profound neglect of the affected side. Spontaneous recovery may occur during this phase.
Subacute phase (weeks to months): Symptoms may gradually improve with rehabilitation. Compensatory strategies are learned and implemented.
Chronic phase (months to years): Some level of neglect may persist long-term. Rehabilitation can continue to improve function and quality of life. The exact trajectory is highly variable depending on the individual and the severity of the initial insult.
Important Considerations
Variability: The presentation of unilateral neglect can vary significantly from person to person.
Co-occurring conditions: Unilateral neglect often co-occurs with other cognitive impairments, such as aphasia, apraxia, and memory deficits.
Impact on daily life: Unilateral neglect can have a significant impact on a person's ability to perform everyday activities and participate in social and occupational activities.
Rehabilitation: Early and intensive rehabilitation is essential for maximizing recovery.
Prognosis: The prognosis for unilateral neglect varies depending on the severity of the brain damage, the individual's response to rehabilitation, and the presence of other cognitive impairments.
Caregiver support: Caregivers play a crucial role in supporting individuals with unilateral neglect. Educating caregivers about the condition and providing them with strategies to help the individual is essential.