Approaches to Stroke Rehabilitation

Rehabilitation of Visual and Perceptual Deficits after Stroke

Perception is the ability of the brain to interpret sensory information from the environment. Perceptual deficits that impact function are visual field deficits, decreased body awareness, neglect of the involved side, visual inattention, apraxia (poor motor planning), and figure ground (inability to locate objects in the environment). Treatment programs include sensory and perceptual integration with activities of daily living. To increase body awareness and reduce neglect, repetitive functional training with activities of daily living, such as pen and paper tasks, standardized computer and card activities, and sensory stimulation of the affected side may be utilized. Visual markers and visual scanning tasks help stroke survivors to compensate for visual inattention. To facilitate motor planning, stroke survivors must simplify complex activities and be given verbal and sensory cues during functional activities. Reduction of environmental stimuli may help to minimize figure ground deficits. Stroke survivors with visual field deficits must be taught to turn their heads frequently to the involved side to increase accuracy with reading, writing, and driving.

Unilateral spatial agnosia, sometimes called neglect, is a type of perceptual deficit that affects up to 85% of patients to some degree of severity. It is defined as a "single modality recognition deficit". Some patients who have a stroke experience an impairment where they may not recognize common objects (visual agnosia), may not identify or recognize certain sounds or voices (auditory agnosia), and may not recognize objects by feeling their shape (sensory agnosia). They may also have difficulty orienting to stimuli on the affected side of the body.

Visual agnosia includes hemiachromatopsia (loss of color perception), akineopsia (no recognition of faces), and alexia (lack of recognition of written letters. Auditory agnosia (inability to recognize familiar voices) includes pure word deafness (inability to repeat or understand spoken language with no language deficit present). Sensory agnosia includes loss of pain perception, poor spatial orientation.

One of the most significant problems in treating agnosia is that the patient is typically unaware of the existence or extent of their deficit and is, therefore, resistant to therapy. Patients may also lack motivation to change. The goal of therapy is to help the patient become aware of their deficits and teach them compensation strategies with alternate modalities. For example, a patient with pure word blindness may benefit from tracing letters or the patient with pure word deafness may benefit from learning to read lips using facial expressions as contextual cues to help comprehension.