Cognitive-perceptual rehabilitation addresses the impairments, functional limitations, and disabilities that result from a deficit in cognition or perception. Cognition refers to the mental processes of comprehension, judgment, memory, and reasoning. Perception is part of the cognitive process, and is characterized by the conscious recognition and interpretation of sensory stimuli for knowledge or motivation of action.
Individuals who have neurological insult (trauma to the brain ), whether mild or severe, may experience cognitive and perceptual difficulties. Researchers have found that 75-90% of children with learning disabilities present with motor difficulties, which often are accompanied by perceptual deficits. In one study, over half of patients admitted for cognitive rehabilitation due to head injury also presented with visual perceptual impairments. In addition, individuals who have experienced strokes or inflammatory or infectious brain diseases, such as meningitis or encephalitis, are at risk for perceptual and cognitive disorders.
Cognitive and perceptual rehabilitation is indicated when a patient or client presents with deficits in these areas during the medical, physical therapy, or occupational therapy assessment. Difficulties may appear in equilibrium and vestibular functions, automatic postural reactions, fine and visual motor performance, motor planning abilities, and/or sensory integration. The individual may remember events incorrectly and have difficulty perceiving new information. In addition, he or she may have inappropriate responses to sensory input due to deficits in sensory processing.
Unilateral spatial inattention, a visual perceptual dysfunction occurring most frequently in patients who have had a stroke, traumatic brain injury, or tumor, may be detected by asymmetries in performance. For example, in drawing a clock, the individual may place all of the numbers on the right half of the clock only. When an individual has visual, auditory, or tactile agnosia, he or she is unable to recognize and name a common object using one of the senses of sight, hearing, or touch, respectively. Visuospatial disorders are manifested by the inability to discern spatial relationships. Visuoconstructive disabilities occur when an individual is unable to synthesize parts into a whole, such as building a tower from blocks or copying a line drawing. Vestibular impairments may present as dizziness or imbalance with certain movements or head positions. Many standardized tests exist to assess perceptual performance in children or adults.
Intervention is found in either direct therapy or indirect therapy. Direct therapy usually focuses on the particular tasks or skills to be learned, with compensatory behaviors filling in for abilities that are missing. In contrast, indirect therapy focuses on rehabilitating the underlying dysfunction of the central nervous system (CNS), in hopes that improvement of the dysfunction will transfer to skill attainment.
Sensory integration and motor control approaches are considered indirect therapies. Sensory integration is an approach, used often with children, in which sensory input is provided within the context of a meaningful activity, usually play-related. The goal is that the child will display appropriate responses and gain experience in organization of sensory input. When using the motor control approach, task-oriented behavior is practiced to enhance perceptual information from the feedback and feedforward mechanisms in the CNS. Verbal and visual cues, in addition to varying the practice situation, are all used to assist in facilitating appropriate performance that can be applied to a variety of situations.
An example of direct therapy is functionally relevant motor skill training. Balance, locomotion, body awareness, and eye-hand coordination tasks are practiced in the context of activities of daily living, e.g., tying a shoe. Tasks are broken down into simple parts, then as a whole, and practiced in a variety of ways for carryover to different situations. Visual perceptual rehabilitation usually takes the form of direct therapy as well. Clients are trained to use eye and head movements along with visual markers to scan their environment, compensating for unilateral spatial inattention. Clients with visuospatial and visuoconstructive disorders are trained by progressing from simple to more complex tasks, using verbal, proprioceptive, and vestibular input to aid in performing the tasks. Treatment of vestibular impairments takes place in a similar fashion. The patient is habituated to certain head movements through practice, then is progressed to more complex ones as tolerance increases.
Cognitive prosthetics, another form of direct therapy, may be used in the rehabilitation of an individual with impairments in brain processes. Prosthetics, in the form of computer technology, are used to compensate for the individual's impairments by altering the environment for optimum function. Highly individualized computer software is used to provide an individual with the support necessary to successfully perform tasks of daily living. For example, it may sequence steps of a task, or convert written words to pictures or speech.
Regardless of the interventions selected, the underlying strategies for working with an individual who has cognitive-perceptual dysfunction are similar. Goals should be clear and relevant to the patient to reduce confusion and increase motivation. In the beginning, the complex should be broken down into simple parts with verbal, visual, tactile, or other cues provided as necessary. Distractions in the environment should be decreased at first. As progress is made, tasks then move toward more complexity.
Progress may be slow, depending upon the severity of disability, individual motivation, family support, etc. The desired outcome, however, is that the individual learns to better modulate and discriminate sensory input in order to process it and respond to it appropriately. This may occur as an actual change in neural function, or through the use of compensatory measures. An increase in functional ability and reduction in disability are the ultimate goals.
Health care team roles
Cognitive-perceptual rehabilitation truly requires a transdiciplinary approach. Any or all of the following individuals may be involved, depending upon the specific needs of the individual: family physician, neurologist, psychiatrist, ophthalmologist, otologist, psychologist, occupational therapist, physical therapist, speech and language pathologist, recreational therapist, and vocational education specialist.
Feedback— Peripheral sensory input which indicates a need for correction of errors.
Feedforward— The use of previous motor learning to anticipate errors in movement planning, allowing for advance correction.
Proprioceptive— Pertaining to sensations of body movements and position.
Sensory integration— The processing and organization of sensory input.
Unilateral spatial inattention— Perceptual unawareness of stimuli on one side of the body, associated with a cortical or subcortical lesion in the opposite side of the brain.
Vestibular— Pertaining to the inner ear structures associated with balance and position sense.
Shumway-Cook, Anne, and Marjorie Woollacott. Motor Control: Theory and Practical Applications. Baltimore, MD: Williams & Wilkins, 1995.
Umphred, Darcy A. Neurological Rehabilitation. 3rd ed. St. Louis, MO: Mosby Yearbook, Inc, 1995.
Cole, Elliot. "Cognitive Prostethics: An Overview to a Method of Treatment." NeuroRehabilitation 12 (1999): 39-51.