Spatial Neglect

What is Spatial Neglect?

Spatial neglect syndrome is a behavioral disorder also referred to as unilateral or hemineglect syndrome. This condition can be tricky to diagnose, even for specialists who are well-versed with it. Typically, patients with this condition have difficulty orienting themselves in space, often on their non-dominant side (frequently the left side). This problem arises after an issue in the right side of the brain, specifically in the right posterior parietal cortex.

It’s important to understand that spatial neglect syndrome doesn’t just affect sensory and motor skills-it can also influence perception, spatial understanding, behavior, and other factors. One of the main challenges of this condition is that patients often have difficulty recognizing their own deficits, a situation referred to as anosognosia. Additionally, they may experience emotional dysfunction.

Spatial neglect syndrome can vary greatly due to the different locations and extent of brain damage in each patient. After an injury to the right side of the brain, the left side often becomes more active, which results in attention and eye movements shifting towards the right side. When spatial neglect syndrome is present, it generally indicates that the patient may have difficulty functioning independently in the long term.

Medical professionals use the Kessler Foundation Neglect Assessment Process (KF-NAP) or the Conley Scale scores to assess the severity of the patient’s unilateral neglect. By understanding this syndrome better, patients and their cares can help manage the condition and its potentially debilitating effects more effectively.

What Causes Spatial Neglect?

A disturbance in the structure and function of the brain can lead to an issue called spatial biasing. This is a disorder affecting mental processes and it’s most commonly caused by a type of stroke that happens in the half of the brain that is less in control, often the right half. This type of stroke, specifically affecting a major artery on the right side of the brain, can cause disorientation in about 80% of the patients in the early stages.

There are a few other things that can cause spatial biasing, like injuries to the brain, tumors, and formations of aneurysms (which are bulges or “ballooning” in the blood vessels) in the brain. It’s also worth noting that while diseases that cause brain cells to decay over time can lead to this disorder, it’s pretty rare.

Risk Factors and Frequency for Spatial Neglect

Strokes that occur in the left hemisphere of the brain happen more often than those on the right, with incidence rates of 54% to 43% respectively. However, a condition called spatial neglect is noticeably more common in patients who have had a right-sided stroke. On average, up to 82% of stroke patients can experience this disorder, specifically affecting around 50% of individuals.

Age seems to be a significant factor in stroke patients developing spatial neglect, as opposed to factors such as which hand they use most (handedness) or their gender. In fact, a case study found that a majority of patients with neglect were above the age of 65, with fewer under this age encountering this issue.

Furthermore, individuals of low socioeconomic status and those who identify as white have been reported to have a stronger correlation with spatial neglect.

Signs and Symptoms of Spatial Neglect

Post-stroke spatial neglect syndrome is a condition that can develop in patients who have had a previous stroke. Gathering a detailed medical history, focusing on factors such as uncontrolled high blood pressure or diabetes, irregular medication use, personality disorders, epilepsy, migraines, or balance issues, is crucial. This syndrome’s symptoms don’t usually come from the patients themselves due to a symptom called anosognosia, which means they don’t realize their deficiencies. Changes in behavior, struggling to get dressed, or use the side of their body opposite to the stroke are usual symptoms. Most often, family members or caregivers report these changes.

Types of spatial processing impairments include:

• Perception-attention neglect: The patient may not notice events on the side affected by the neglect, even if their sensation is fine.
• Motor intentional aiming deficits: Despite the physical ability to move the neglected side of the body, the patient could struggle to initiate or perform movements.
• Representational neglect: This is when a patient has a deficit in creating mental images of scenes or objects on the left side.

Behavioral changes that might be noticed include:

• Anosognosia: Unawareness of the deficit.
• Self-neglect: Patients typically ignore the left side of their body and only perform tasks with the right side.
• Anosodiaphoria: This refers to a patient’s lack of concern about their deficit.

In a physical examination, signs of spatial neglect syndrome could include:

• Creating a consistent avoidance of the right side of the body.
• Allochiria: An unusual visual experience where patients respond to the right side of their body as if stimuli were presented there, even when it actually was on the left.

In some cases, patients might develop a false belief that the neglected side of their body belongs to someone else, a condition called somatoparaphrenia. This belief can lead to severe consequences, such as ignoring left-sided chest pain which could be due to a serious condition like a heart attack. Patients might also display peripersonal or extrapersonal neglect, which means they may be unable to reach out in either the area within reaching distance or outside of it.

Testing for Spatial Neglect

If your doctor suspects you have hemineglect syndrome, they will conduct a full neurological examination, lab tests, and imaging studies. Hemineglect syndrome is a condition where a person ignores one side of their world, usually following a stroke. It can make it hard for someone to notice things on one side of their body or a room.

The neurological examination can involve different tests.

1) The Cancellation Test: Here, you’ll look at a piece of paper with scattered lines and you’re asked to cross or circle all the lines. If you only cross lines on one side and leave the other side uncrossed, this may suggest you have hemineglect syndrome.

2) Line Bisection Test (LBT): With this test, you’d have to mark the center of a long line drawn on a paper. If you end up marking more towards right and ignore the left, it might suggest you have this condition. The longer it takes you to perform this test, the more severe the neglect might be.

3) Drawing/Copying Test: In this, you’ll be asked to draw something from your memory or to copy a given task.

4) Multitasking/Double-Simultaneous stimulation: This test checks if you neglect one side when there are multiple tasks to handle at once. For example, the doctor might ask you to count fingers shown in both your vision fields.

5) Reading Test: If you read only the right side and ignore the left side in a sequence like “460225”, it might suggest hemineglect syndrome.

Aside from these tests, your doctor may also run lab tests to rule out other causes like dementia, depression, and stroke. These can include tests for vitamin-B12 level, homocysteine level, thyroid function tests and blood sugar level tests.

For visual confirmation of issues in the brain, like a stroke or brain tumor, your doctor may request imaging studies like CT scans or MRI scans of your brain. CT scans are quick and effective for emergencies, while MRI scans may offer more detailed images and can be preferred if the CT scan doesn’t reveal enough information. In cases where issues with brain blood supply are suspected, CT angiography or MR angiography can be useful. In certain cases, a conventional angiography might be used, this is a more sensitive test but is also more invasive.

Treatment Options for Spatial Neglect

Treating patients dealing with neglect typically involves a mix of rehabilitation therapies and certain medications.

Rehabilitation includes activities like visual exploration, motor therapy for sensory defects, and neck muscle vibration or focusing attention on the overlooked side. It’s important for patients to have a detailed visual assessment from an eye specialist to determine if the problem is caused by a primary visual disorder or neglect. After this evaluation, visual scanning training can begin, training patients to consciously look in the neglected areas.

For any defects related to motor or sensory functions, occupational therapists can use several therapies, as suggested by the American Heart Association and the American Occupational Therapy Association. They recommend two therapies:

1) Prism Adaptation Treatment: This cost-effective and highly beneficial therapy has patients undergo ten sessions in 14 days. They repeatedly move the healthier side of their body while wearing optical prisms, which also triggers unconscious movement on the neglected side. The prisms’ main function is to shift the visual image a little towards the affected area.

2) Limb activation and optokinetic stimulation: Limb activation therapy maybe once or twice per week for three months, prompts the patient to move their affected limb towards the neglected side following sensory or verbal stimuli. This strategy directly evaluates spatial motor systems and indirect attention function.

Patients with this condition usually don’t respond to commands or other stimuli in their surroundings. In order to determine the primary cause of this behavior, a neuropsychological evaluation should be performed early on. Additionally, therapies such as speech, occupational and physical should also be administered.

Medically, spatial neglect is most commonly a secondary condition after a stroke. Certain type of medications known as Cholinesterase inhibitors, such as rivastigmine or donepezil, are typically used as the primary treatment for cognitive impairments in patients who’ve experienced strokes.

Stimulants, like methylphenidate, have been shown to be helpful in patients dealing with neglect, according to a clinical trial. However, other medications such as benzodiazepines, anticholinergic, antidopaminergic, and sedatives/ hypnotics are usually avoided as they can cause resolved symptoms to reappear, or even cause delirium in neglect patients.

What else can Spatial Neglect be?

If a person is suspected to have spatial neglect, a condition where they’re not aware of one side of their body or space, doctors would consider several other conditions that have similar symptoms. These include:

• Ataxic hemiparesis: a condition that results in weakness and lack of coordinated movements on one side of the body
• Gerstmann syndrome: a disorder that makes a person unable to do math calculations, recognize their fingers, write, and distinguish left from right
• Balint syndrome: a condition that makes a person unable to see more than one thing at a time in their visual field, and fail to reach an item with their right hand, but able to do it with their left hand
• Anton syndrome: a situation where a person is blind but insists they can see
• Primary somatosensory or motor disturbances: changes or issues in the processes related to physical sensation or movement
• Other common non-neurological conditions, like depression, conversion disorder, and problems with the balance system (vestibular dysfunction) and so on

These are all conditions that a doctor needs to rule out before making a diagnosis of spatial neglect.

What to expect with Spatial Neglect

The recovery outlook for patients suffering from neglect depends heavily on how quickly the disorder is identified. Reports indicate that initially, about 80% of patients go undiagnosed. As a result, an accurate diagnosis becomes a key factor in ensuring a patient’s well-being, especially for those recovering from a stroke.

There are tests that can provide insight into a patient’s recovery progress. For example, the cancellation test can help predict the rate of recovery and functionality of a patient six months after suffering from a stroke.

Fortunately, many patients with neglect can show signs of improvement during the recovery phase after a stroke due to the re-establishment of blood flow and reduction of swelling in the brain. This increase in brain activity, especially on the left frontal and right parietal regions of the brain, aids recovery.

At the end of 12 weeks, reports show that neglect is present in 17% of patients with right-brain damage and 5% of those with left-brain damage. Unfortunately, this means approximately 23% of affected individuals may face longer hospital stays and increased health complications due to frequent falls. Consequently, their ability to perform work duties can decline significantly, especially if they have neglect alongside anosognosia, a condition in which a person is unaware of their own illness or disability.

Possible Complications When Diagnosed with Spatial Neglect

Hemispatial Neglect (HSN) can lead to a variety of complex issues for both the patient and their caregivers.

• Difficulty Fulfilling Occupational Duties: HSN can make it difficult for patients to carry out their job responsibilities. This is mostly due to vision and movement perception problems on one side.
• Increased Chance of Delirium: There is a higher likelihood of delirium, a state of mental confusion, among stroke patients with neglect. In fact, one study found that up to 48% of patients who have had a stroke developed delirium.
• Safety Concerns: Safety can become an issue due to patients’ inability to speak clearly or respond quickly in emergencies, making activities like driving unsafe.
• Longer Recovery Time: Spatial neglect can draw out the recovery time for stroke survivors aiming to regain independence. This can consequently increase stress levels for those caring for them.

Preventing Spatial Neglect

Hemineglect syndrome is a serious condition that can severely impact a patient’s quality of life and even be life-threatening. Therefore, it’s very important for doctors and nurses to educate other healthcare team members and anyone providing care to the patient about this condition and its potential effects on the patient’s daily life. Sometimes, the patient may not be active, may not speak, or may not show emotions, which can look like depression or a lack of motivation. So, it’s important for the patient’s family members to understand this and receive thorough guidance on how to support their loved one.

It’s also crucial for patients, their families, and caregivers to understand that even after treatment, some challenges, such as issues with daily tasks and getting around, may continue. Recognizing this can help manage expectations and plan better for the patient’s care and support.