The Journal of
ARCHIVES 1983 - 2010
A Publication for the Therapist, Family and Patient
Reprinted from the March / April 1986 issue:
A Process Approach
Odie L. Bracy Ph.D.
The brain injured patient typically exhibits a multitude of physical and neurological disabilities and symptoms that are often apparent even to an untrained observer. Less obvious cognitive impairments and emotional problems can easily be overlooked during the rehabilitation process. During the acute stage of an injury, it is understandable that the focus of treatment be directed toward life threatening conditions and physical injuries. However, all too often cognitive, emotional, and social issues are not adequately addressed even in the later stages of rehabilitation. Unfortunately, these very issues may be the determinants of placement, of return to work or school, and subsequent adjustment to daily living (Ayres, 1973; Bracy, 1983; Dikman, Reitan, and Tempkin, 1983; Oddy, Humphrey, and Uttley, 1978; Weddell, Oddy and Jenkins, 1980). In many cases when patients are discharged to less structured environments, to return to school or to return to work, the cognitive problems quickly become apparent. It is not unusual to come across head injured individuals in nursing homes or in their own homes who are unable to participate in any meaningful way in work or social settings, but who have received little or no cognitive rehabilitation therapy. Often the families have received little, if any, counseling or preparation for working with their head injured loved one outside the institutional setting.
The term rehabilitation may have a somewhat different meaning when it is applied to cognitive and psychological rather than to physical areas of impairment. To many patients and their families, rehabilitation has the connotation of restoration when applied to the physical aspects of an injury such as cuts, bruises, and broken bones. When healing has occurred, it is anticipated that the patient will once again use the limb or muscle, hopefully with only scars and slightly decreased functioning as reminders of the injury. In contrast to this viewpoint rehabilitation of the cognitive aspects of brain injury should not be viewed as restoration, but as retraining and relearning experiences. In addition, damage to the brain often means lifelong impairments that affect the life of the individual far beyond the scars and specific lost functions. Even slight cognitive dysfunction can result in loss of job, termination of educational activities, difficulties with spouse and/or other family members and problems with social interaction. These problems require adjustment on the part of the individual both to the changes in ability and the effects those changes have on the individual's life and life style.
Observation of brain injured patients may suggest many tasks and activities which patients must relearn if they are to function independently. Activities such as toileting, dressing, eating, and conversing, among others, are frequently affected and require attention during the rehabilitation treatment. However, many therapists are beginning to look beyond these immediate needs and ask the questions of 1) what brain processes have been disrupted in brain injured patients that interfere with their being able to function, learn and develop for themselves, and 2) how do we as therapists address those processes in rehabilitation treatment (Bracy, 1983; Haffey, 1983; Luria, 1973; Weeks, 1982)?
To fully and independently function, the brain injured person must acquire the ability to interact with the environment, even in novel situations, and perceive, plan, make decisions and act, based upon the person's own analysis. In order for patients to achieve this level of functioning, comprehensive rehabilitation must not only include provisions for teaching daily living skills. A good portion of the rehabilitation effort must be directed toward the specific interrupted brain processes that contribute to the more complex cognitive operations.
Cognition and cognitive operations include not only intellectual functioning, memory, language abilities and other such skills, but also functions that influence and are influenced by emotions, social feelings, and psychological functioning. A comprehensive rehabilitation program should provide for evaluation, training, and interaction in all of these life areas.
Therapeutic activities referred to as cognitive rehabilitation run the gamut from body sensory stimulation (Ayres, 1973; Farber, 1982) to computerized treatment exercises (Bracy, 1983; Lynch, 1983). The settings in which these activities are conducted range from intensive care wards, to home-based outpatient services.
Areas of Concern for Cognitive Rehabilitation
Reviews of the histories of neuropsychology and of research concerning the brain and its functions show major shifts in the conceptualization of brain functioning (Hecaen and Albert, 1978; Luria, 1973; Luria, 1980; Walsh, 1978). While a policy of openendedness and frequent reevaluation of our theoretical positions may be most conducive to the advancement of our science, having a theoretical position from which to work gives focus to our efforts. Ideally, the best of the philosophies and activities will be revealed by the sharing of our ideas and how implementation of those ideas have worked with our patients. Until that time, we should not close our minds to theories or activities different from our own, but rather assess whether what we are doing could be enhanced by incorporation of the ideas of others.
Every therapist should have some conception of normal brain functioning, of how injury disrupts normal functioning and of why it is that what they are doing with the patient could be therapeutic. In other words, a theory of brain functioning and of rehabilitation is necessary for assessment diagnosis, treatment planning, goal setting and for providing therapy. Without a unifying and guiding theoretical framework, our efforts would not amount to much more than random stabs in the dark. So I would like to begin by presenting the basics of the theory that we utilize at the NeuroScience Center of Indianapolis and which led to the development of our computerized therapy tasks.
There is no doubt that the theoretical formulations of brain functioning presented by Alexander Luria have influenced my own thinking more than those of any other single individual. Luria described three brain areas which he called functional units. He believed that functional units were involved in all complex mental activity. The first unit includes the brain stem and other subcortical areas and is involved in regulating tone (level of excitation and wakefulness). Regulation of the level of arousal is accomplished by a network of nerves referred to as the reticular formation. The reticular formation appears to have both activating and inhibiting mechanisms that exert a wide spread and general influence as well as specific influences over the entire nervous system. Injury to this area can drastically affect the performance of any and all other brain areas, causing decreased ability to analyze, recall, respond, etc..
The second unit consists of the surface of the brain extending over the top to the side (temporal) areas and over the posterior (back most) areas. This functional unit is involved in receiving, analyzing and storing information. Different areas of the second functional unit are involved in the reception of tactile, visual, auditory, and kinesthetic sensory information. Each of the sensory areas of this unit is comprised of primary zones that receive information, secondary zones that organize and further process the information, and tertiary zones where information from different areas is integrated and combined.
The third unit includes the frontal areas and is involved in the programming of actions, the regulation of behavior in accordance with the program and the verification that the actual behavior is in compliance with the program and the demands of the task. The primary area of the third unit is the motor cortex area that serves as the site of motor impulse output to the periphery. However, this area is responsible only for the final output and not for motor programs. The secondary zone, or premotor area, plays a major role in programming and organizing movement. The tertiary zones of the
frontal lobe "play a decisive role in the formation of intentions and programmes, and in the regulation and verification of the most complex forms of
human behavior" (The Working Brain, p. 84).
Luria stated that "Each form of conscious activity is always a complex functional system and takes place through the combined working of all three
brain units, each of which makes its own contribution" (The Working Brain, p. 99).
According to Luria, the observable behaviors are complex functional systems comprised of many basic processes. The basic processes are contributions from many levels and sites within the brain that come together like "constellations" to produce functional systems which in turn produce observable and measurable behavior. It is the disruption of the basic processes that disrupt functional systems and result in changes in behavior and ability. The changes can be extremely subtle and almost unnoticeable or they can profoundly affect an individual's ability to interact or function.
Understanding of the contribution of different brain areas and processes to complex functional systems is necessary in order to analyze and understand either normal or injury impaired behavior. For instance, suppose a brain injured individual is experiencing difficulty with assembling the pieces necessary to duplicate a simple pattern. Would it be sufficient to say that the person has a visuospatial problem stemming from
right hemisphere parietal lobe damage? Further analysis of the functional system might reveal other ways in which the same deficit could be caused. The problem might be caused by impairment of visual perception, attention, conceptualization of visual input, motor programming, visual/motor integration, regulatory skills or self monitoring/verification skills. These processes might involve injury of the frontal lobes, left hemisphere injury, subcortical injury or as stated earlier, right hemisphere injury. Of more importance than the actual location may be the knowledge of the impaired processes, as this knowledge might help predict behavior in other situations and suggest treatment strategies.
We have found a slightly expanded conceptualization of functional systems, based upon Luria's model, to be helpful in both assessment and treatment of our patients. The first and most basic involves the area Luria refers to as the First Functional Unit (Figure 1). This area plays an important role in the level of arousal, alertness and responsivity of the individual. The second area of interest includes those processes and brain areas involved in sensation and the initial processing of sensory information. It includes the sensory receptors, nerve pathways, intermediate nuclei,
subcortical centers and the primary sensory areas of the cortex (Figure 2).
Figure 1. The shaded areas play a primary role in the individuals level of arousal, alertness and responsivity.
Figure 2. The shaded areas include those processes and brain areas involved in sensation and the initial processing of sensory information.
Figure 3. The third area of interest includes those brain areas and processes involved in integration of sensory information, perception, conception and memory.
Figure 3. The fourth area includes locations and processes involved in response planning, general cognitive organization, execution of motor programs and other executive functions.
A third area of interest includes those brain areas and functional processes involved with integration of sensory information, perception, conception and memory (Figure 3).
A final area includes those brain areas and basic processes involved in response planning, general cognitive organization, execution of motor programs and other executive functions (Figure 4). As can be seen from the figures, the areas and processes referred to as executive in nature are
included in every system and those referred to as intermediate and subcortical are included in most.
The more complex mental activities are based upon the foundations processes of elementary sensory analysis and integration, and elementary motor processes as depicted in our illustrations.
If disruption of basic processes is producing the changes that can be observed in the brain injured person, then it seems reasonable that rehabilitation activities address the source of the problem rather than, or at least, in addition to, the more complex behavioral activities traditionally addressed in rehabilitation therapy.
Our definition of cognitive rehabilitation then, is that "Cognitive rehabilitation is the reattainment of the mental abilities required to successfully and
accurately receive sensory input, process information and act in a manner as independently and appropriately as is possible, given physiological limitations, following insult to, and compromise of, the brain and its functions".
The cognitive impairment produced by a brain injury may be apparent in an individual's loss of ability to recall information, handle money, tell time, understand instructions, drive, make decisions or return to work or school; however, these difficulties in performing specific tasks are not cognitive impairments - they are manifestations of impairment of basic cognitive processes.
Treatment at the level of the complex behavior might appear successful in that the patient might be taught to perform a particular task. However, the
person's ability to learn such tasks independently or to generalize the training to other similar tasks might not be enhanced at all by such treatment. If, on the other hand, a person could be retrained in basic processes of attending, perceiving, analyzing, problem solving, organizing and implementing, then they might reacquire basic abilities that would transcend specific settings and particular tasks and allow the head injured individual to more easily learn complex behaviors and generalize what is learned to other situations.
The basic processes that appear most important are the abilities to:
1) Accurately sense from the environment and the body. This implies that receptors, nerve pathways and primary cortical areas are intact and functioning properly.
2) Attend to sensory information. Attending here refers to a general awareness such as of discomfort heat, or irritation. Conscious thought might not be involved but a response may be emitted in reaction to the stimulation.
3) Focus on sensory input. This implies an attentional focus, a more conscious process.
4) Maintain that focus for an extended period. Although an extremely attractive stimulus may magnetically produce sustained attention, this refers more to attention maintained by the effort of the individual.
5) Extract detail from the information sensed. A quantitative and qualitative analysis is implied. The entire stimulus situation provides a gestalt from which details must be discerned and processed in order for the information to be useful.
6) Attach meaning to sensory input. This infers a process of comparison of the gestalt and details of the current situation with those details experienced previously to determine novelty, familiarity, recognition, etc.; in short, perception.
7) Attend to multiple stimuli simultaneously. Up until this point reference has been to basic processes conducted on a single stimulus. This is a giant step in that at this point events one through six are occurring simultaneously for many stimulus situations which are also constantly occurring simultaneously.
8) Shift from detail to detail spatially. At any one moment in time numerous stimuli are impinging upon the nervous system both internally and externally. The individual must attend to the spatial gestalt formed by a particular stimulus, picking out and relating to details presented
simultaneously (i.e., such as in one frame of a movie film).
9) Shift from stimulus to stimulus spatially. This is similar to number eight but much larger in scope as the whole process must be simultaneously occurring for many simultaneously occurring stimuli.
10) Track from detail to detail temporally. Every detail of each stimulus is linked in time to the details of the next moment in time. The process occurring in step eight occurs at a single frozen moment. Process ten involves linking together the details of differing moments such that relationships are perceived and evolving situations are recognized.
11) Track from stimulus to stimulus temporally. This is a more complex process than number ten in that it involves performing the processes mentioned in ten for many stimuli resulting in a higher level of information integration.
12) Relate information temporally and spatially. This is a further evolution of the last four (8-11) processes in that relationships perceived spatially and temporally are integrated.
13) Integrate new with stored information. This is considered a higher level perception in which the information currently being processed is further compared and integrated with past learning, experiences, etc. Memory skills come into play in a much greater way.
14) Integrate different sensory input. Processes 1-13 may be completed within single sensory areas. This process implies the combination and
integration of the information from many or all of the sensory areas.
15) Integrate perceptions. This is a higher level process by which the perceptions formed, based upon single sensory mechanisms, are integrated to form one general gestalt encompassing the total stimulus situation.
16) Form new concepts from analysis of current input and stored information. This involves some level of abstraction, the ability to generate hypotheses and the ability to predict and suppose when data are not complete.
17) Generate programs of action. Motor programming of responses is implied. This involves preparing for both the content of the response and the motor actions necessary to convey that content.
18) Coordinate programs temporally and execute sequentially. Apraxic behavior would be an example of a breakdown in this process area.
19) Control muscle activity (to initiate and inhibit). On a basic level, this simply refers to the ability to carry out a motor action or to stop that action. On a higher level it also refers to an executive type control over whether or not what is in thought actually gets executed. 20) Monitor behavior and compare against program. This involves analysis of sensory input from both internal and external sources for the purpose of facilitating the execution of the motor program.
21) Alter behavior to maintain program. This refers to the ability to alter a response sufficiently to keep it within the plan if the motor response being executed is deviating in any way from the planned program. The deviation could be produced by effects of environmental conditions or impaired ability to perform the planned program.
22) Profit from feedback to maintain or alter program. This involves analysis and monitoring of the execution of a motor response on a higher level. The analysis determines if the response being executed is having the desired effect on the environmental or stimulus situation. If it is not having that effect this information is utilized to alter the motor program.
23) Store information, program, consequences, alternatives, conclusions. This involves organizing information, encoding it and placing it in memory.
24) Retrieve stored information. This implies a higher level memory function than referred to in number 16 above. Conscious recall and the ability to verbalize past events, old information, etc. is implied.
Normal cognitive development during infancy and early childhood appears to be an inherent process of the brain to deal with and overcome disharmony produced by environmental demands. Piaget proposed the terms assimilation and accommodation as two processes utilized in cognitive development to overcome environmental demands. It seems reasonable that these same inherent abilities to develop and to overcome demands could be used in retraining or cognitive rehabilitation activities. This is not to say that the developmental sequences need to be recapitulated but simply that we attempt to take advantage of the brain's inherent capacity to attempt to overcome obstacles.
Our task in treatment planning would then become one of assessing the patient to determine what brain processes have been disrupted and designing our treatment tasks so that demands are placed upon the brain to use those disrupted processes. The demands must, at first, be of the most simple nature possible. As the patient becomes able to better overcome the simple demands, the tasks should be increased in level of complexity and in the demands upon the patient. The list of basic processes presented earlier represent a hierarchy of most-simple to most complex
cognitive processes. Therapy should be designed, at first, to address the more simple processes and advance as the patient develops. The specific tasks presented to the patient are unimportant in and of themselves, as long as they place demands on the targeted process.
Therapy to rehabilitate the basic cognitive processes is not meant to replace content related therapy (such as education, daily living skills, etc.), physical therapy, psychotherapy or any other important area of concern. Successful therapy at the basic level will, in my experience, enhance responses to other therapy activities. The purpose of therapy should be rehabilitation to the extent that the patient is able to think, perceive, make decisions and effect responses with minimal or no assistance from others. Successful retraining of basic processes, or teaching (when processes prove unable to be retrained), may result in such rehabilitation. Neglect of this area of therapy may result in producing an individual who can only do
activities specifically taught and then only under specific conditions.
Brain injured persons are very unique individuals in spite of the apparent similarities in the impairment that occur with specific types of brain injury. They typically display a mosaic of strengths and deficits that result from an interaction of the effects of the injury, the prior levels of physical and cognitive functioning and the personal, emotional and social adjustment prior to injury. Knowledge of the "prior to injury" status is important for a more complete understanding of the patient's current intellectual, physical, emotional and social skills. Cognitive impairment produced by brain injury may involve functional systems and brain processes such that many of the following areas of functioning are affected: sensation, perception, conception, language and speech skills, visuospatial skills, memory, emotions, motor programming and response. These skills are all areas of concern for those involved with cognitive rehabilitation. We must know the capabilities of our patients in each area in order to focus our treatment, determine the proper modes for presenting our therapy tasks to the patient and to determine what we can expect from our patients in the way of response.
Theories attempting to explain recovery of cognitive functions involve one or more of the following explanations:
- The release of compensatory skills (Jackson, J.H., selected writings) such that lower level brain areas assume control.
- The substitution of intact cognitive skills, behavioral strategies or different brain areas (i.e. opposite hemisphere) to replace the impaired or lost skills (Fritsch & Hitzig, 1870; Gazzaniga, 1970).
- The return of normal functioning following cessation of shock effects projected from a distant damaged areas (disachisis) (Von Monakow, 1914).
- The recovery of functioning through retraining (Luria, 1973).
While all of these explanations may play a role in the recovery of cognitive functioning it is clear that the therapist has the most control over activity involving the fourth area, cognitive retraining.
According to Luria, rehabilitation involves a reorganization of functional systems so that new methods of performing old behaviors are acquired. The retraining requires challenging and repetitive exercises within a planned program that addresses and places demands upon the individual to perform the impaired skill. The program must be planned for a hierarchical stepwise approach so that easier and less complex components of the task are presented and mastered first.
A second strategy of rehabilitation involves teaching compensation skills that will enable an individual to accomplish a task. This refers to actually learning a new procedure that will physically enable a person to perform a task. Whether or not a facility or a professional explicitly acknowledges the application of these two principles it is clear that any therapy procedure or exercise addresses one or both of the principles. Specifically an exercise is designed to instruct the patient in physical procedures that will compensate for, or work around, the existing physical or cognitive impairment; or an exercise is intended to place a cognitive demand upon the patient to perform a certain cognitive skill involving memory, perception, language processing, etc. to facilitate the reacquiral of the cognitive skill.
It seems reasonable therefore to state that the more successful therapy programs will be those in which the treatment team can correctly assess the
areas of impairment to be addressed by the treatment program, formulate the most appropriate steps by which to approach the treatment and implement the program with good techniques.
As stated earlier, both patients and their families may have emotional, psychological and social needs that must also be addressed. Psychotherapy and counseling are vital aspects of the rehabilitation procedure.
The strategies that I have addressed above can be applied to any rehabilitation setting from acute care to outpatient therapy settings. The theory does not dictate the actual tasks to be presented. There are many tasks that could be employed to address the processes involved in attention, memory, perception and the other cognitive processes specified earlier. What appears most important is that tasks are utilized which address the processes adequately (challenges that will require assimilation and accommodation) and in a proper hierarchy based upon complexity. This point also applies to therapy designed to teach daily living skills.
Success in a rehabilitation program should be measured in terms of the progress obtained toward the patient's full potential rather than in terms of full restoration. However, the professional must take care not to underestimate this potential. Careful analysis of the patients abilities present prior to the injury and careful formulation and implementation of a treatment plan is mandatory.
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