Balint's syndrome, identified by the Austro-Hungarian neurologist Rezső Bálint in 1909,^[1][2] is a disjointed psychic paralysis of gaze with haphazard scanning. It is improperly characterized by "optic ataxia" (incoordination of hand and eye movement, those with Balint syndrome grasp for them as if blind), "oculomotor apraxia" (the inability to voluntarily guide eye movements/ change to a new location of visual fixation). Due to cortical gaze paralysis, patients also have simultanagnosia (the inability to perceive more than one object at a time, even when in the same place). Balint's syndrome is the result of visual binding deficits.

[edit] Neuroanatomical evidence

Balint'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 strokes, Alzheimer's disease, intracranial tumors, or brain injury. Multifocal leukoencephalopathy and Creutzfeldt-Jacob disease have also been found to cause this kind of damage. This syndrome is caused by damage to the posterior superior watershed areas aka the parietal-occipital vascular border zone (Brodmann's areas 19 and 7). Balint's syndrome has only recently been reported in children.^[3] In children this syndrome results in a variety of occupational difficulties, but most notably difficulties in schoolwork, especially reading.

[edit] Case Studies

Symptoms of Balint’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^[4]. 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 Balint’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^[5] from the Boston Diagnostic Aphasia Examination. A patient with congenital deafness exhibited partial Balint’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^[6].

[edit] Treatment

Treatment for Balint's syndrome usually takes advantage of an adaptive functional approach, where the individual's strengths are utilized in order to address his or her difficulties. Two additional treatments of Balint’s syndrome have also been developed. The remedial approach aims to restore the damaged CNS by training in perceptual skills. Tabletop activities and sensorimotor tasks are suggested for this approach. The intended outcome of this approach is to generalize skills to everyday living. The next approach is called the multicontext approach. This approach involves practicing a targeted strategy in an environment with varied tasks and movement demands. It also incorporates self awareness tasks^[7] .

[edit] References