Balint's syndrome
Encyclopedia
Bálint's syndrome is an uncommon and incompletely understood triad of severe neuropsychological impairments: inability to perceive the visual field as a whole (simultanagnosia), difficulty in fixating the eyes (ocular apraxia), and inability to move the hand to a specific object by using vision (optic ataxia). It was named in 1909 for the Austro-Hungarian neurologist
Rezső Bálint
who first identified it.
Bálint's syndrome occurs most often with an acute onset as a consequence of two or more strokes at more or less the same place in each hemisphere. Therefore, it occurs rarely. The most frequent cause of complete Bálint's syndrome is said by some to be sudden and severe hypotension, resulting in bilateral borderzone infarction in the occipito-parietal region. More rarely, cases of progressive Bálint's syndrome have been found in degenerative disorders such as Alzheimer's disease or certain other traumatic brain injuries at the border of the parietal and the occipital lobes of the brain.
Lack of awareness of this syndrome may lead to a misdiagnosis and resulting inappropriate or inadequate treatment. Therefore, clinicians should be familiar with Bálint's syndrome and its various etiologies.
In many cases the complete trio of symptoms—inability to perceive the visual field as a whole (simultanagnosia), difficulty in fixating the eyes (ocular apraxia), and inability to move the hand to a specific object by using vision (optic ataxia)—may not be noticed until the patient is in rehabilitation. Therapists unfamiliar with Bálint's syndrome may misdiagnose a patient's inability to meet progress expectations in any of these symptom areas as simply indicating incapability of benefiting from further traditional therapy. The very nature of each Bálint symptom frustrates rehabilitation progress in each of the other symptoms. Much more research is needed to develop therapeutic protocols that address Bálint symptoms as a group since the disabilities are so intertwined.
This spatial disorder of visual attention—the ability to identify local elements of a scene, but not the global whole—has been referred to as a constriction of the individual's global gestalt window—their visual "window" of attention. People fixate their eyes to specific images in social scenes because they are informative to the meaning of the scene. Any forthcoming recovery in simultanagnosia may be related to somehow expanding the restricted attentional window that characterizes this disorder.
Simultanagnosia is a profound visual deficit. It impairs the ability to perceive multiple items in a visual display, while preserving the ability to recognize single objects. One study suggests that simultanagnosia may result from an extreme form of competition between objects which makes it difficult for attention to be disengaged from an object once it has been selected. Patients with simultanagnosia have a restricted spatial window of visual attention and cannot see more than one object at a time. They see their world in a patchy, spotty manner. Therefore, they pick out a single object, or even components of an individual object, without being able to see the global "big picture."
A study which directly tested the relationship between the restriction of the attentional window in simultanagnosia compared with the vision of healthy participants with normal limits of visual processing confirmed the limitations of difficulties of patients with simultanagnosia.
There is considerable evidence that a person's cortex is essentially divided into two functional streams: an occipital-parietal-frontal pathway that processes "where" information and an occipital-temporal-frontal pathway that provides "what" information to the individual.
Apraxia of speech, also known as verbal apraxia or dyspraxia, is a speech disorder in which a person has trouble saying what he or she wants to say correctly and consistently. Apraxia of speech is often present along with another speech disorder called aphasia
. At times, a completely different word or action is used than the one the person intended to speak or make. The person is often aware of the mistake.
Bálint referred to this as "psychic paralysis of gaze"—the inability to voluntarily guide eye movements, changing to a new location of visual fixation. The most frequent and disabling deficit is the syndrome of unilateral spatial neglect that manifests as a bias of spatial representation and attention on the same side as the lesion. Also significant is that the disturbances of space representation are more frequent and severe after traumatic damage to the right hemisphere.
There is no single factor or test that can be used to diagnose apraxia. In addition, speech-language experts do not agree about which specific symptoms are part of developmental apraxia.
In some cases, people with acquired apraxia of speech recover some or all of their speech abilities on their own. In other cases, speech-language therapy, tailored to the individual and designed to treat other speech or language problems that may occur together with apraxia, is often helpful.
Optic ataxia is also known as misreaching or dysmetria
(difficult to measure), secondary to visual perceptual deficits. A patient with Bálint's syndrome likely has defective hand movements under visual guidance, despite normal limb strength. The patient is unable to grab an object while looking at the object, due to a discoordination of eye and hand movement. It is especially true with their contralesional hand.
Dysmetria refers to a lack of coordination of movement, typified by the undershoot or overshoot of intended position with the hand, arm, leg, or eye. It is sometimes described as an inability to judge distance or scale.
The reaching ability of the patient is also altered. It takes them longer to reach toward an object. Their ability to grasp an object is also impaired. The patient's performance is even more severely deteriorated when vision of either the hand or the target is prevented.
s, Alzheimer's disease
, intracranial tumor
s, or brain injury. Multifocal leukoencephalopathy and Creutzfeldt-Jakob disease have also been found to cause this kind of damage. This syndrome is caused by damage to the posterior superior watershed
areas, also known as the parietal
-occipital
vascular border zone (Brodmann's areas 19 and 7).
the development of visually guided manual movements,
and the improvement of the integration of visual
elements. Very few treatment strategies have been proposed, and some of those have been criticized as being poorly developed and evaluated.
Three approaches to rehabilitation of perceptual deficits, such as those seen in Bálint's syndrome, have been identified:
The Web site "Medfriendly" is one of the few sites found to contain structured therapeutic techniques that provide the patient with immediate feedback.
A study of a patient with Corticobasal Ganglionic Degeneration (CGBD) also showed a development of Bálint’s syndrome. As a result of CGBD, the patient developed an inability to move his eyes to specific visual objects in his peripheral fields. He also was unable to reach out and touch objects in his peripheral fields. An inability to recognize more than one item at a time was also experienced when presented with the Cookie Theft Picture from the Boston Diagnostic Aphasia Examination
.
A 58-year old male presented with Bálint's syndrome secondary to severe traumatic brain injury 4-months post-injury onset. He had completed a comprehensive post-acute brain injury rehabilitation program. He received 6 months of rehabilitation services as an inpatient. A three-pronged approach included the implementation of (a) compensatory strategies, (b) remediation exercises and (c) transfer of learned skills in multiple environments and situations. Comprehensive neuropsychological and occupational therapy evaluations were performed at admission and at discharge. Neuropsychological test improvements were noted on tasks that assess visuospatial functioning, although most gains were noted for functional and physical abilities.
A patient with congenital deafness exhibited partial Bálint’s syndrome symptoms. This patient experienced an inability to perceive simultaneous events in her visual field. She was also unable to fixate and follow an object with her eyes. In addition, her ability to point at targets under visual guidance was impaired.
Bálint's syndrome is rarely reported in children, but some recent studies provide evidence that cases do exist in children. A case involving a 10-year-old male child with Bálint's syndrome has been reported. Similar results were seen in a 7-year-old boy. In children this syndrome results in a variety of occupational difficulties, but most notably difficulties in schoolwork, especially reading. The investigators encourage more careful recognition of the syndrome to allow adequate rehabilitation and environmental adaptation.
Neurologist
A neurologist is a physician who specializes in neurology, and is trained to investigate, or diagnose and treat neurological disorders.Neurology is the medical specialty related to the human nervous system. The nervous system encompasses the brain, spinal cord, and peripheral nerves. A specialist...
Rezső Bálint
Rezso Bálint (physician)
Rezső Bálint was an Austro-Hungarian neurologist and psychiatrist notable as the discoverer of Balint's syndrome. He is not to be confused with the contemporary Hungarian landscape painter of the same name.-References:...
who first identified it.
Bálint's syndrome occurs most often with an acute onset as a consequence of two or more strokes at more or less the same place in each hemisphere. Therefore, it occurs rarely. The most frequent cause of complete Bálint's syndrome is said by some to be sudden and severe hypotension, resulting in bilateral borderzone infarction in the occipito-parietal region. More rarely, cases of progressive Bálint's syndrome have been found in degenerative disorders such as Alzheimer's disease or certain other traumatic brain injuries at the border of the parietal and the occipital lobes of the brain.
Lack of awareness of this syndrome may lead to a misdiagnosis and resulting inappropriate or inadequate treatment. Therefore, clinicians should be familiar with Bálint's syndrome and its various etiologies.
Symptoms
Bálint's syndrome symptoms can be quite debilitating since they impact visuospatial skills, visual scanning and attentional mechanisms. Since it represents impairment of both visual and language functions, it is a significant disability that can affect the patient's safety─even in one's own home environment, and can render the person incapable of maintaining employment.In many cases the complete trio of symptoms—inability to perceive the visual field as a whole (simultanagnosia), difficulty in fixating the eyes (ocular apraxia), and inability to move the hand to a specific object by using vision (optic ataxia)—may not be noticed until the patient is in rehabilitation. Therapists unfamiliar with Bálint's syndrome may misdiagnose a patient's inability to meet progress expectations in any of these symptom areas as simply indicating incapability of benefiting from further traditional therapy. The very nature of each Bálint symptom frustrates rehabilitation progress in each of the other symptoms. Much more research is needed to develop therapeutic protocols that address Bálint symptoms as a group since the disabilities are so intertwined.
Simultanagnosia
Simultanagnosia is the inability to perceive simultaneous events or objects in one's visual field. Victims of Bálint's syndrome perceive the world erratically, as a series of single objects rather than seeing the wholeness of a scene.This spatial disorder of visual attention—the ability to identify local elements of a scene, but not the global whole—has been referred to as a constriction of the individual's global gestalt window—their visual "window" of attention. People fixate their eyes to specific images in social scenes because they are informative to the meaning of the scene. Any forthcoming recovery in simultanagnosia may be related to somehow expanding the restricted attentional window that characterizes this disorder.
Simultanagnosia is a profound visual deficit. It impairs the ability to perceive multiple items in a visual display, while preserving the ability to recognize single objects. One study suggests that simultanagnosia may result from an extreme form of competition between objects which makes it difficult for attention to be disengaged from an object once it has been selected. Patients with simultanagnosia have a restricted spatial window of visual attention and cannot see more than one object at a time. They see their world in a patchy, spotty manner. Therefore, they pick out a single object, or even components of an individual object, without being able to see the global "big picture."
A study which directly tested the relationship between the restriction of the attentional window in simultanagnosia compared with the vision of healthy participants with normal limits of visual processing confirmed the limitations of difficulties of patients with simultanagnosia.
There is considerable evidence that a person's cortex is essentially divided into two functional streams: an occipital-parietal-frontal pathway that processes "where" information and an occipital-temporal-frontal pathway that provides "what" information to the individual.
Ocular apraxia
Ocular apraxia is exemplified by the inability to carry out familiar movements when asked to do so. Persons with apraxia understand such commands and are willing to carry them out. However, they are physically unable to perform the task.Apraxia of speech, also known as verbal apraxia or dyspraxia, is a speech disorder in which a person has trouble saying what he or she wants to say correctly and consistently. Apraxia of speech is often present along with another speech disorder called aphasia
Aphasia
Aphasia is an impairment of language ability. This class of language disorder ranges from having difficulty remembering words to being completely unable to speak, read, or write....
. At times, a completely different word or action is used than the one the person intended to speak or make. The person is often aware of the mistake.
Bálint referred to this as "psychic paralysis of gaze"—the inability to voluntarily guide eye movements, changing to a new location of visual fixation. The most frequent and disabling deficit is the syndrome of unilateral spatial neglect that manifests as a bias of spatial representation and attention on the same side as the lesion. Also significant is that the disturbances of space representation are more frequent and severe after traumatic damage to the right hemisphere.
There is no single factor or test that can be used to diagnose apraxia. In addition, speech-language experts do not agree about which specific symptoms are part of developmental apraxia.
In some cases, people with acquired apraxia of speech recover some or all of their speech abilities on their own. In other cases, speech-language therapy, tailored to the individual and designed to treat other speech or language problems that may occur together with apraxia, is often helpful.
Optic ataxia
Optic ataxia is the inability to guide the hand toward an object using visual information where the inability cannot be explained by motor, somatosensory, visual field deficits or acuity deficits. Optic ataxia is seen in Bálint's syndrome where it is characterized by an impaired visual control of the direction of arm-reaching to a visual target, accompanied by defective hand orientation and grip formation. It is considered a specific visuomotor disorder, independent of visual space misperception.Optic ataxia is also known as misreaching or dysmetria
Dysmetria
Dysmetria refers to a lack of coordination of movement typified by the undershoot or overshoot of intended position with the hand, arm, leg, or eye...
(difficult to measure), secondary to visual perceptual deficits. A patient with Bálint's syndrome likely has defective hand movements under visual guidance, despite normal limb strength. The patient is unable to grab an object while looking at the object, due to a discoordination of eye and hand movement. It is especially true with their contralesional hand.
Dysmetria refers to a lack of coordination of movement, typified by the undershoot or overshoot of intended position with the hand, arm, leg, or eye. It is sometimes described as an inability to judge distance or scale.
The reaching ability of the patient is also altered. It takes them longer to reach toward an object. Their ability to grasp an object is also impaired. The patient's performance is even more severely deteriorated when vision of either the hand or the target is prevented.
Cause
The visual difficulties in Bálint's syndrome are usually due to damage to the top part of the temporal-occipital lobes on both sides of the brain. The temporal lobe is on the side of the brain by the ear and the occipital lobe is the back part of the brain. Thus, the temporal-occipital lobes refer to the sides and back parts of the brain. In Balint's syndrome, the top part of the parietal lobes on both sides of the brain may also be affected. The parietal lobes are the middle area of the top part of the brain.Diagnosis
Lack of awareness of the syndrome may lead to misdiagnosis such as blindness, psychosis, or dementia. Symptoms of Bálint's syndrome are most likely to be noticed first by therapists providing rehabilitation following brain lesions. However, due to the scarcity among practitioners of familiarity with the syndrome, the symptoms are often explained away incorrectly without being considered as a possibility and followed by medical confirmation of clinical and neuroradiological findings. Any severe disturbance of space representation, spontaneously appearing following bilateral parietal damage, strongly suggests the presence of Bálint's syndrome and should be investigated as such. One study reports that damage to the bilateral dorsal occipitoparietal regions appeared to be involved in Bálint's syndrome.Neuroanatomical evidence
Bálint's syndrome has been found in patients with bilateral damage to the posterior parietal cortex. The primary cause of the damage and the syndrome can originate from multiple strokeStroke
A stroke, previously known medically as a cerebrovascular accident , is the rapidly developing loss of brain function due to disturbance in the blood supply to the brain. This can be due to ischemia caused by blockage , or a hemorrhage...
s, Alzheimer's disease
Alzheimer's disease
Alzheimer's disease also known in medical literature as Alzheimer disease is the most common form of dementia. There is no cure for the disease, which worsens as it progresses, and eventually leads to death...
, intracranial tumor
Brain tumor
A brain tumor is an intracranial solid neoplasm, a tumor within the brain or the central spinal canal.Brain tumors include all tumors inside the cranium or in the central spinal canal...
s, or brain injury. Multifocal leukoencephalopathy and Creutzfeldt-Jakob disease have also been found to cause this kind of damage. This syndrome is caused by damage to the posterior superior watershed
Watershed area (medical)
Watershed area is the medical term referring to regions of the body that receive dual blood supply from the most distal branches of two large arteries, such as the splenic flexure of the large intestine....
areas, also known as the parietal
Parietal lobe
The parietal lobe is a part of the Brain positioned above the occipital lobe and behind the frontal lobe.The parietal lobe integrates sensory information from different modalities, particularly determining spatial sense and navigation. For example, it comprises somatosensory cortex and the...
-occipital
Occipital lobe
The occipital lobe is the visual processing center of the mammalian brain containing most of the anatomical region of the visual cortex. The primary visual cortex is Brodmann area 17, commonly called V1...
vascular border zone (Brodmann's areas 19 and 7).
Manifestations
Some telltale signs suggesting Bálint's syndrome following bilateral brain insults may include:- limitation to perceive only stimuli that is presented at 35 to 40 degrees to the right. They are able to move their eyes but cannot fixate on specific visual stimuli. (ataxia)
- patient's field of attention is limited to one object at a time. making activities like reading difficult because each letter is perceived separately.(ataxia)
- figure/ground defects in which a patient can see either the background but not the object residing somewhere in the whole scene, or conversely can see the object but sees no background around it (simultanagnosia)
- a patient, while attempting to put one foot into a slipper by trying to insert the foot into a nonexistent foot several inches from the slipper, even as the patient focuses on the actual slipper (oculomotor apraxia)
- a patient raising a fork or spoon containing food to a point on the patient's face above or below the mouth, and possibly finding the mouth by trial and error by manually moving the utensil on the face (optic ataxia)
Treatment
In terms of the specific rehabilitation of visuoperceptual disorders such as Bálint’s syndrome, the literature is extremely sparse. According to one study, rehabilitation training should focus on the improvement of visual scanning,the development of visually guided manual movements,
and the improvement of the integration of visual
elements. Very few treatment strategies have been proposed, and some of those have been criticized as being poorly developed and evaluated.
Three approaches to rehabilitation of perceptual deficits, such as those seen in Bálint's syndrome, have been identified:
- The adaptive (functional) approach, which involves functional tasks utilising the person’s strengths and abilities, helping them to compensate for problems or altering the environment to lessen their disabilities. This is the most popular approach.
- The remedial approach, which involves restoration of the damaged CNS by training in the perceptual skills, which may be generalised across all activities of daily living. This could be achieved by tabletop activities or sensorimotor exercises.
- The multicontext approach, which is based on the fact that learning is not automatically transferred from one situation to another. This involves practicing of a targeted strategy in a multiple environment with varied tasks and movement demands, and it incorporates self-awareness tasks.
The Web site "Medfriendly" is one of the few sites found to contain structured therapeutic techniques that provide the patient with immediate feedback.
- For each of these techniques, the degree of structure decreases as the task becomes more familiar.
- The structure decreases to levels that are more likely to be encountered in the patient's environment.
- Before any of these techniques can be used, the patient needs to admit that the problems exists and believe that they can learn to trust their vision.
- Helping the patient focus on more than one thing at a time and to improve the ability to tell things apart with vision. In this technique, flash cards are shown to the patient with two lines on them. The patient is asked if the two lines look the same or different. The answer is written on the back of the flash card. If the angles are different, the degree of difference is noted on the back of the card as well. By using this technique, the patient can get immediate feedback as to whether he/she perceives things accurately. Also, a family member can use the flash cards with the patient or the patient can use them by him or herself.
- Different types of flashcards can also be used to help the patient focus on the general aspect of something instead of only focusing on the details. The flashcards have a clock face on the front with all 12 numbers. Once the patient is used to this, the clocks only have the numbers 12, 3, 6, and 9 on them. Finally, the numbers are faded out and the patient is asked to tell what time it is based only on the hands of the clock. This requires focusing on the details to answer a general question based on visual information. The time is written in digital form on the back of the cards so the patient can get immediate feedback.
- Some patient's with Balint's syndrome only respond to part of what they see when the object(s) is close up. Thus, one strategy is to determine how far the patient can see and to place the object(s) farther away in the field of vision. In some cases, this helps the patient improve the ability to see the entire object and not just a part of it.
- Since people with Balint's syndrome cannot look into the sides of their visual field, techniques can be used to improve the person's ability to scan visual patterns quickly. The visual field is the space that someone can see without moving the eyes. Some techniques to improve visual ability include having the patient make wide head turns towards the areas that he/she cannot see when looking straight ahead. Such wide head turns help the patient gather more information about the environment.
- Reading material that is in the area that the person has difficulty seeing can be marked with an up and down red line. By doing this, the patient will see the red line and be more aware of their difficulty attending to that area of the page. This, in turn, can allow the patient to be sure to focus more attention on that particular area of the page.
- To improve optic ataxia (inability to move the hand to an object by using vision), exercises can be done that require eye/hand coordination and manipulating objects with the hands. Using tools would be an example as would be catching a ball. Obviously, safe tools should be used and it is often helpful to start the ball-catching exercise with a ball made of crunched up paper. The patient can then progress to balls that travel faster when thrown (e.g., tennis balls). This task can be made more difficult by bouncing the ball against a wall first.
Some case studies
Symptoms of Bálint’s syndrome were found in the case of a 29-year-old migraine sufferer. In the aura before the migraine headache, she experienced an inability to see all of the objects in the visual field simultaneously; an inability to coordinate hand and eye movements; and an inability to look at an object on command. Symptoms were not present before the onset of the migraine or after it passed.A study of a patient with Corticobasal Ganglionic Degeneration (CGBD) also showed a development of Bálint’s syndrome. As a result of CGBD, the patient developed an inability to move his eyes to specific visual objects in his peripheral fields. He also was unable to reach out and touch objects in his peripheral fields. An inability to recognize more than one item at a time was also experienced when presented with the Cookie Theft Picture from the Boston Diagnostic Aphasia Examination
Boston Diagnostic Aphasia Examination
The Boston Diagnostic Aphasia Examination or BDAE is a test used to evaluate adults suspected of having aphasia, and is currently in its third edition. It was created by Harold Goodglass and Edith Kaplan...
.
A 58-year old male presented with Bálint's syndrome secondary to severe traumatic brain injury 4-months post-injury onset. He had completed a comprehensive post-acute brain injury rehabilitation program. He received 6 months of rehabilitation services as an inpatient. A three-pronged approach included the implementation of (a) compensatory strategies, (b) remediation exercises and (c) transfer of learned skills in multiple environments and situations. Comprehensive neuropsychological and occupational therapy evaluations were performed at admission and at discharge. Neuropsychological test improvements were noted on tasks that assess visuospatial functioning, although most gains were noted for functional and physical abilities.
A patient with congenital deafness exhibited partial Bálint’s syndrome symptoms. This patient experienced an inability to perceive simultaneous events in her visual field. She was also unable to fixate and follow an object with her eyes. In addition, her ability to point at targets under visual guidance was impaired.
Bálint's syndrome is rarely reported in children, but some recent studies provide evidence that cases do exist in children. A case involving a 10-year-old male child with Bálint's syndrome has been reported. Similar results were seen in a 7-year-old boy. In children this syndrome results in a variety of occupational difficulties, but most notably difficulties in schoolwork, especially reading. The investigators encourage more careful recognition of the syndrome to allow adequate rehabilitation and environmental adaptation.