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The prognosis for individuals with apraxia varies. With therapy, some patients improve significantly, while others may show very little improvement. Some individuals with apraxia may benefit from the use of a communication aid.
However, many people with apraxia are no longer able to be independent. Those with limb-kinetic and/or gait apraxia should avoid activities in which they might injure themselves or others.
Occupational therapy, physical therapy, and play therapy may be considered as other references to support patients with apraxia. These team members could work along with the SLP to provide the best therapy for people with apraxia. However, because people with limb apraxia may have trouble directing their motor movements, occupational therapy for stroke or other brain injury can be difficult.
No medication has been shown useful for treating apraxia.
Treatment for individuals with apraxia includes speech therapy, occupational therapy, and physical therapy.
Generally, treatments for apraxia have received little attention for several reasons, including the tendency for the condition to resolve spontaneously in acute cases. Additionally, the very nature of the automatic-voluntary dissociation of motor abilities that defines apraxia means that patients may still be able to automatically perform activities if cued to do so in daily life. Nevertheless, research shows that patients experiencing apraxia have less functional independence in their daily lives, and that evidence for the treatment of apraxia is scarce. However, a literature review of apraxia treatment to date reveals that although the field is in its early stages of treatment design, certain aspects can be included to treat apraxia. One method is through rehabilitative treatment, which has been found to positively impact apraxia, as well as activities of daily living. In this review, rehabilitative treatment consisted of 12 different contextual cues, which were used in order to teach patients how to produce the same gesture under different contextual situations. Additional studies have also recommended varying forms of gesture therapy, whereby the patient is instructed to make gestures (either using objects or symbolically meaningful and non-meaningful gestures) with progressively less cuing from the therapist. It may be necessary for patients with apraxia to use a form of alternative and augmentative communication depending on the severity of the disorder. In addition to using gestures as mentioned, patients can also use communication boards or more sophisticated electronic devices if needed. No single type of therapy or approach has been proven as the best way to treat a patient with apraxia, since each patient's case varies. However, one-on-one sessions usually work the best, with the support of family members and friends. Since everyone responds to therapy differently, some patients will make significant improvements, while others will make less progress. The overall goal for treatment of apraxia is to treat the motor plans for speech, not treating at the phoneme (sound) level. Research suggests that individuals with apraxia of speech should receive treatment that focuses on the repetition of target words and rate of speech. Research rerouted that the overall goal for treatment of apraxia should be to improve speech intelligibility, rate of speech and articulation of targeted words.
Articulation problems resulting from dysarthria are treated by speech language pathologists, using a variety of techniques. Techniques used depend on the effect the dysarthria has on control of the articulators. Traditional treatments target the correction of deficits in rate (of articulation), prosody (appropriate emphasis and inflection, affected e.g. by apraxia of speech, right hemisphere brain damage, etc.), intensity (loudness of the voice, affected e.g. in hypokinetic dysarthrias such as in Parkinson's), resonance (ability to alter the vocal tract and resonating spaces for correct speech sounds) and phonation (control of the vocal folds for appropriate voice quality and valving of the airway). These treatments have usually involved exercises to increase strength and control over articulator muscles (which may be flaccid and weak, or overly tight and difficult to move), and using alternate speaking techniques to increase speaker intelligibility (how well someone's speech is understood by peers). With the speech language pathologist, there are several skills that are important to learn; safe chewing and swallowing techniques, avoiding conversations when feeling tired, repeat words and syllables over and over in order to learn the proper mouth movements, and techniques to deal with the frustration while speaking. Depending on the severity of the dysarthria, another possibility includes learning how to use a computer or flip cards in order to communicate more effectively.
More recent techniques based on the principles of motor learning (PML), such as LSVT (Lee Silverman voice treatment) speech therapy and specifically LSVT may improve voice and speech function in PD. For Parkinson's, aim to retrain speech skills through building new generalised motor programs, and attach great importance to regular practice, through peer/partner support and self-management. Regularity of practice, and when to practice, are the main issues in PML treatments, as they may determine the likelihood of generalization of new motor skills, and therefore how effective a treatment is.
Augmentative and alternative communication (AAC) devices that make coping with a dysarthria easier include speech synthesis and text-based telephones. These allow people who are unintelligible, or may be in the later stages of a progressive illness, to continue to be able to communicate without the need for fully intelligible speech.
Given the complexity of the medical problems facing ideomotor apraxia patients, as they are usually suffering from a multitude of other problems, it is difficult to ascertain the impact that it has on their ability to function independently. Deficits due to Parkinson's or Alzheimer's disease could very well be sufficient to mask or make irrelevant difficulties arising from the apraxia. Some studies have shown ideomotor apraxia to independently diminish the patient's ability to function on their own. The general consensus seems to be that ideomotor apraxia does have a negative impact on independence in that it can reduce an individual's ability to manipulate objects, as well as diminishing the capacity for mechanical problem solving, owing to the inability to access information about how familiar parts of the unfamiliar system function. A small subset of patients has been known to spontaneously recover from apraxia; this is rare, however. One possible hope is the phenomenon of hemispheric shift, where functions normally performed by one hemisphere can shift to the other in the event that the first is damaged. This seems to necessitate, however, that some portion of the function is associated with the other hemisphere to begin with. There is dispute over whether the right hemisphere of the cortex is involved at all in the praxis system, as some evidence from patients with severed corpus callosums indicates it may not be.
Although there is little that can be done to substantially reverse the effects of ideomotor apraxia, Occupational Therapy can be effective in helping patients regain some functional control. Sharing the same approach in treating ideational apraxia, this is achieved by breaking a daily task (e.g. combing hair) into separate components and teaching each distinct component individually. With ample repetition, proficiency in these movements can be acquired and should eventually be combined to create a single pattern of movement.
Developmental verbal dyspraxia is a developmental inability to motor plan volitional movement for the production of speech in the absence of muscular weakness. Research has suggested links to the FOXP2 gene.
There are many potential causes of dysarthria. They include toxic, metabolic, degenerative diseases, traumatic brain injury, or thrombotic or embolic stroke.
Degenerative diseases include parkinsonism, amyotrophic lateral sclerosis (ALS), multiple sclerosis, Huntington's disease, Niemann-Pick disease, and Friedreich ataxia.
Toxic and metabolic conditions include: Wilson's disease, hypoxic encephalopathy such as in drowning, and central pontine myelinolysis.
These result in lesions to key areas of the brain involved in planning, executing, or regulating motor operations in skeletal muscles (i.e. muscles of the limbs), including muscles of the head and neck (dysfunction of which characterises dysarthria). These can result in dysfunction, or failure of: the motor or somatosensory cortex of the brain, corticobulbar pathways, the cerebellum, basal nuclei (consisting of the putamen, globus pallidus, caudate nucleus, substantia nigra etc.), brainstem (from which the cranial nerves originate), or the neuro-muscular junction (in diseases such as myasthenia gravis) which block the nervous system's ability to activate motor units and effect correct range and strength of movements.
Causes:
- Brain tumor
- Cerebral palsy
- Guillain–Barré syndrome
- Hypothermia
- Lyme disease
- Stroke
- Intracranial hypertension (formerly known as pseudotumor cerebri)
- Tay-Sachs, and late onset Tay-Sachs (LOTS), disease
There is no cure for DVD/CAS, but with appropriate, intensive intervention, people with the disorder can improve significantly.
DVD/CAS requires various forms of therapy which varies with the individual needs of the patient. Typically, treatment involves one-on-one therapy with a speech language pathologist (SLP). In children with DVD/CAS, consistency is a key element in treatment. Consistency in the form of communication, as well as the development and use of oral communication are extremely important in aiding a child's speech learning process.
Many therapy approaches are not supported by thorough evidence; however, the aspects of treatment that do seem to be agreed upon are the following:
- Treatment needs to be intense and highly individualized, with about 3-5 therapy sessions each week
- A maximum of 30 minutes per session is best for young children
- Principles of motor learning theory and intense speech-motor practice seem to be the most effective
- Non-speech oral motor therapy is not necessary or sufficient
- A multi-sensory approach to therapy may be beneficial: using sign language, pictures, tactile cues, visual prompts, and Augmentative and Alternative Communication (AAC) can be helpful.
Although these aspects of treatment are supported by much clinical documentation, they lack evidence from systematic research studies. In ASHA's position statement on DVD/CAS, ASHA states there is a critical need for collaborative, interdisciplinary, and programmatic research on the neural substrates, behavioral correlates, and treatment options for DVD/CAS.
Many researchers are investigating the characteristics of apraxia of speech and the most effective treatment methods. Below are a couple of the recent findings:
Sound Production Treatment:
Articulatory-kinematic treatments have the strongest evidence of their use in treating Acquired Apraxia of Speech. These treatments use the facilitation of movement, positioning, timing, and articulators to improve speech production. Sound Production Treatment (SPT) is an articulatory-kinematic treatment that has received more research than many other methods. It combines modeling, repetition, minimal pair contrast, integral stimulation, articulatory placement cueing, and verbal feedback. It was developed to improve the articulation of targeted sounds in the mid-1990s. SPT shows consistent improvement of trained sounds in trained and untrained words. The best results occur with eight to ten exemplars of the targeted sound to promote generalization to untrained exemplars of trained sounds. In addition, maintenance effects are the strongest with 1–2 months post-treatment with sounds that reached high accuracy during treatment. Therefore, the termination of treatment should not be determined by performance criteria, and not by the number of sessions the client completes, in order to have the greatest long-term effects. While there are many parts of SPT that should receive further investigation, it can be expected that it will improve the production of targeted sounds for speakers with apraxia of Speech.
Repeated Practice & Rate/Rhythm Control Treatments:
Julie Wambaugh’s research focuses on clinically applicable treatments for acquired apraxia of speech. She recently published an article examining the effects of repeated practice and rate/rhythm control on sound production accuracy. Wambaugh and colleagues studied the effects of such treatment for 10 individuals with acquired apraxia of speech. The results indicate that repeated practice treatment results in significant improvements in articulation for most clients. In addition, rate/rhythm control helped some clients, but not others. Thus, incorporating repeated practice treatment into therapy would likely help individuals with AOS.
In cases of acute AOS (stroke), spontaneous recovery may occur, in which previous speech abilities reappear on their own. All other cases of acquired AOS require a form of therapy; however the therapy varies with the individual needs of the patient. Typically, treatment involves one-on-one therapy with a speech language pathologist (SLP). For severe forms of AOS, therapy may involve multiple sessions per week, which is reduced with speech improvement. Another main theme in AOS treatment is the use of repetition in order to achieve a large amount of target utterances, or desired speech usages.
There are various treatment techniques for AOS. One technique, called the Linguistic Approach, utilizes the rules for sounds and sequences. This approach focuses on the placement of the mouth in forming speech sounds. Another type of treatment is the Motor-Programming Approach, in which the motor movements necessary for speech are practiced. This technique utilizes a great amount of repetition in order to practice the sequences and transitions that are necessary in between production of sounds.
Research about the treatment of apraxia has revealed four main categories: articulatory-kinematic, rate/rhythm control, intersystemic facilitation/reorganization treatments, and alternative/augmentative communication.
- Articulatory-kinematic treatments almost always require verbal production in order to bring about improvement of speech. One common technique for this is modeling or repetition in order to establish the desired speech behavior. Articulatory-kinematic treatments are based on the importance of patients to improve spatial and temporal aspects of speech production.
- Rate and rhythm control treatments exist to improve errors in patients’ timing of speech, a common characteristic of Apraxia. These techniques often include an external source of control like metronomic pacing, for example, in repeated speech productions.
- Intersystemic reorganization/facilitation techniques often involve physical body or limb gestural approaches to improve speech. Gestures are usually combined with verbalization. It is thought that limb gestures may improve the organization of speech production.
- Finally, alternative and augmentative communication approaches to treatment of apraxia are highly individualized for each patient. However, they often involve a "comprehensive communication system" that may include "speech, a communication book aid, a spelling system, a drawing system, a gestural system, technologies, and informed speech partners".
One specific treatment method is referred to as PROMPT. This acronym stands for Prompts for Restructuring Oral Muscular Phonetic Targets, and takes a hands on multidimensional approach at treating speech production disorders. PROMPT therapists integrate physical-sensory, cognitive-linguistic, and social-emotional aspects of motor performance. The main focus is developing language interaction through this tactile-kinetic approach by using touch cues to facilitate the articulatory movements associated with individual phonemes, and eventually words.
One study describes the use of electropalatography (EPG) to treat a patient with severe acquired apraxia of speech. EPG is a computer-based tool for assessment and treatment of speech motor issues. The program allows patients to see the placement of articulators during speech production thus aiding them in attempting to correct errors. Originally after two years of speech therapy, the patient exhibited speech motor and production problems including problems with phonation, articulation, and resonance. This study showed that EPG therapy gave the patient valuable visual feedback to clarify speech movements that had been difficult for the patient to complete when given only auditory feedback.
While many studies are still exploring the various treatment methods, a few suggestions from ASHA for treating apraxia patients include the integration of objective treatment evidence, theoretical rationale, clinical knowledge and experience, and the needs and goals of the patient
Treatment consists of physical rehabilitation programs designed to improve overall function, increase strength and improve balance. The ultimate goal is to increase the patient's degree of independence, thus improving the patient's quality of life. Exercise typically begins with simple movements, gradually transitioning into more complex actions. Various aspects of treatment are assessed based on the individual patient's condition, utilizing many assessment tools:
- Functional Reach Test
- External Perturbation Test – Push, Release
- External Perturbation Test – Pull
- Clinical Sensory Integration Test
- Single Leg Stance Test
- Five Times Sit to Stand Test
Various scales are also utilized
- Brief Ataxia Rating Scale
- Friedreich's Ataxia Impact Scale
- Scale For Assessment and Rating of Ataxia
Motor speech disorders are a class of speech disorders that disturb the body's natural ability to speak due to neurologic impairments. These neurologic impairments make it difficult for individuals with motor speech disorders to plan, program, control, coordinate, and execute speech productions. Disturbances to the individual's natural ability to speak vary in their etiology based on the integrity and integration of cognitive, neuromuscular, and musculoskeletal activities. Speaking is an act dependent on thought and timed execution of airflow and oral motor / oral placement of the lips, tongue, and jaw that can be disrupted by weakness in oral musculature (dysarthria) or an inability to execute the motor movements needed for specific speech sound production (apraxia of speech or developmental verbal dyspraxia). Such deficits can be related to pathology of the nervous system (central and /or peripheral systems involved in motor planning) that affect the timing of respiration, phonation, prosody, and articulation in isolation or in conjunction.
"For many years, it was thought that postural and balance disorders in cerebellar ataxia were not treatable. However, the results of several recent studies suggest that rehabilitation can relieve postural disorders in patients with cerebellar ataxia...There is now moderate level evidence that rehabilitation is efficient to improve postural capacities of patients with cerebellar ataxia – particularly in patients with degenerative ataxia or multiple sclerosis. Intensive rehabilitation programs with balance and coordination exercises are necessary. Although techniques such as virtual reality, biofeedback, treadmill exercises with supported bodyweight and torso weighting appear to be of value, their specific efficacy has to be further investigated. Drugs have only been studied in degenerative ataxia, and the level of evidence is low."
One approach is that it can be ameliorated to varying degrees by means of Frenkel exercises.
One main objective of the treatment is to re-establish the physiological inhibition exerted by the cerebellar cortex over cerebellar nuclei. Research using Transcranial direct-current stimulation (TCDCS) and Transcranial magnetic stimulation (TMS) shows promising results.
Additionally, mild to moderate cerebellar ataxia may be treatable with buspirone.
It is thought that the buspirone increases the serotonin levels in the cerebellum and so decreases ataxia.
There is no cure for the condition. Management is through therapy.
The most common cause of ideomotor apraxia is a unilateral ischemic lesion to the brain, which is damage to one hemisphere of the brain due to a disruption of the blood supply, as in a stroke. There are a variety of brain areas where lesions have been correlated to ideomotor apraxia. Initially it was believed that damage to the subcortical white matter tracts, the axons that extend down from the cells bodies in the cerebral cortex, was the main area responsible for this form of apraxia. Lesions to the basal ganglia may also be responsible, although there is considerable debate as to whether damage to the basal ganglia alone would be sufficient to induce apraxia. Lesions to these lower brain structures has not, however, been shown to be more prevalent in apraxic patients. In fact, these types of lesions are more common in nonapraxic patients. The lesions most associated with ideomotor apraxia are to the left parietal and premotor areas. Patients with lesions to the supplementary motor area have also presented with ideomotor apraxia. Lesions to the corpus callosum can also induce apraxic-like symptoms, with varying effects on the two hands, although this has not been thoroughly studied. In addition to ischemic lesions to the brain, ideomotor apraxia has also been seen in neurodegenerative disorders such as Parkinson's disease, Alzheimer's disease, Huntington's disease, corticobasal degeneration, and progressive supranuclear palsy.
Developmental verbal dyspraxia (DVD), also known as childhood apraxia of speech (CAS) and developmental apraxia of speech (DAS), is when children have problems saying sounds, syllables, and words. This is not because of muscle weakness or paralysis. The brain has problems planning to move the body parts (e.g., lips, jaw, tongue) needed for speech. The child knows what they want to say, but their brain has difficulty coordinating the muscle movements necessary to say those words. The exact cause of this disorder is unknown. Some observations suggest a genetic cause of DVD, as many with the disorder have a family history of communication disorders. There is no cure for DVD, but with appropriate, intensive intervention, people with this motor speech disorder can improve significantly.
Developmental coordination disorder is a lifelong neurological condition that is more common in males than in females, with a ratio of approximately four males to every female. The exact proportion of people with the disorder is unknown since the disorder can be difficult to detect due to a lack of specific laboratory tests, thus making diagnosis of the condition one of elimination of all other possible causes/diseases. Approximately 5–6% of children are affected by this condition.
There is no curative treatment for this condition. Supportive management is helpful.
Bruns apraxia, or frontal ataxia is a gait apraxia found in patients with bilateral frontal lobe disorders. It is characterised by an inability to initiate the process of walking, despite the power and coordination of the legs being normal when tested in the seated or lying position. The gait is broad-based with short steps with a tendency to fall backwards. It was originally described in patients with frontal lobe tumours, but is now more commonly seen in patients with cerebrovascular disease.
It is named after Ludwig Bruns.
Individuals with cerebellar ataxia have full cognitive awareness: it is usually only the physical deterioration that prohibits them from participating in activities of daily living and any other relevant or desired interests. One of the most significant barriers in the lives of these individuals is dysarthria. Due to their cognitive stability, it is important that people who spend time with individuals with this disease are able to communicate as fully as possible with them. This is necessary in order to improve their day-to-day interactions.
Behavioral intervention is successful when it involves engaging knowledge of the interests and general backgrounds of individuals with cerebellar ataxia. Communication maximizing strategies are also useful, such as exaggeration of articulatory gestures, giving full attention to their responses, repeating where necessary, and slowing down speaking rate. Another intervention technique for speech is to focus on optimizing respiratory and vocal resources as well as training compensatory strategies.
These listed intervention techniques can improve quality of life in individuals with this disease and can be helpful for professionals/clinicians in the field as well as loved ones of those affected.
Oculomotor apraxia (OMA), also known as Cogan ocular motor apraxia or saccadic initiation failure (SIF) is the absence or defect of controlled, voluntary, and purposeful eye movement. It was first described in 1952 by the American ophthalmologist David Glendenning Cogan. People with this condition have difficulty moving their eyes horizontally and moving them quickly. The main difficulty is in saccade initiation, but there is also impaired cancellation of the vestibulo-ocular reflex. Patients have to turn their head in order to compensate for the lack of eye movement initiation in order to follow an object or see objects in their peripheral vision, but they often exceed their target. There is controversy regarding whether OMA should be considered an apraxia, since apraxia is the inability to perform a learned or skilled motor action to command, and saccade initiation is neither a learned nor a skilled action.
In adults, many of the symptoms diminish over time. Although it has been suggested that a similar diminishing of symptoms occurs in children as well, it appears more likely that most do not overcome their deficits, but instead simply learn to adjust.
There is no cure for Gerstmann syndrome. Treatment is symptomatic and supportive. Occupational and speech therapies may help diminish the dysgraphia and apraxia. In addition, calculators and word processors may help school children cope with the symptoms of the disorder.
Since the underlying cause of the disorder is damage to the brain, at present ideational apraxia is not reversible. However, Occupational or Physical Therapy may be able to slow the progression and help patients regain some functional control, with the treatment approach being the same as that of ideomotor apraxia. Some recovery may occur in younger patients after stroke, because brain plasticity may allow the functions of these damaged regions to be remapped. As patients develop new behaviors to cope with their apraxia, their brain's functioning neurons may take on some of the functions of the dead or damaged regions.
In the context of dementia, apraxia is a major cause of morbidity, and progresses with the underlying disease sometimes to the extent that patients may be unable to feed themselves or use simple utensils. Patients often become highly dependent or require nursing home placement because of their inability to properly use objects.
Brain imaging techniques such as fMRI, EEG, and PET scans may help in understanding the neuroanatomical and computational basis of ideational apraxia. Understanding these mechanisms is likely to be crucial in developing new modes of therapy to help patients cope with their disorder.
Agraphia cannot be directly treated, but individuals can be rehabilitated to regain some of their previous writing abilities.
For the management of phonological agraphia, individuals are trained to memorize key words, such as a familiar name or object, that can then help them form the grapheme for that phoneme. Management of allographic agraphia can be as simple as having alphabet cards so the individual can write legibly by copying the correct letter shapes. There are few rehabilitation methods for apraxic agraphia; if the individual has considerably better hand control and movement with typing than they do with handwriting, then they can use technological devices. Texting and typing do not require the same technical movements that handwriting does; for these technological methods, only spatial location of the fingers to type is required. If copying skills are preserved in an individual with apraxic agraphia, repeated copying may help shift from the highly intentional and monitored hand movements indicative of apraxic agraphia to a more automated control.
Micrographia is a condition that can occur with the development of other disorders, such as Parkinson's disease, and is when handwriting becomes illegible because of small writing. For some individuals, a simple command to write bigger eliminates the issue.
- Anagram and Copy Treatment (ACT) uses the arrangement of component letters of target words and then repeated copying of the target word. This is similar to the CART; the main difference is that the target words for ACT are specific to the individual. Target words that are important in the life of the individual are emphasized because people with deep or global agraphias do not typically have the same memory for the words as other people with agraphia may. Writing can be even more important to these people as it can cue spoken language. ACT helps in this by facilitating the relearning of a set of personally relevant written words for use in communication.
- Copy and Recall Treatment (CART) method helps to reestablish the ability to spell specific words that are learned through repeated copying and recall of target words. CART is more likely to be successful in treating lexical agraphia when a few words are trained to mastery than when a large group of unrelated words is trained. Words chosen can be individualized to the patient, which makes treatment more personalized.
- Graphemic buffer uses the training of specific words to improve spelling. Cueing hierarchies and copy and recall method of specific words are used, to work the words into the short-term memory loop, or graphemic buffer. The segmentation of longer words into shorter syllables helps bring words into short-term memory.
- Problem solving approach is used as a self-correcting method for phonological errors. The individual sounds out the word and attempts to spell it, typically using an electronic dictionary-type device that indicates correct spelling. This method takes advantage of the preserved sound-to-letter correspondences when they are intact. This approach may improve access to spelling memory, strengthen orthographic representations, or both.
OMA is a neurological condition. Although some brain imaging studies of people with OMA reveal a normal brain, some MRI studies have revealed unusual appearance of some brain areas, in particular the corpus callosum, cerebellum, and/or fourth ventricle. Oculomotor apraxia can be acquired or congenital. Sometimes no cause is found, in which case it is described as idiopathic
A person may be born with the parts of the brain for eye movement control not working, or may manifest poor eye movement control in childhood. If any part of the brain that controls eye movement becomes damaged, then OMA may develop. One of the potential causes is bifrontal hemorrhages. In this case, OMA is associated with bilateral lesions of the frontal eye fields (FEF), located in the caudal middle frontal gyrus. The FEF control voluntary eye movements, including saccades, smooth pursuit and vergence. OMA can also be associated with bilateral hemorrhages in the parietal eye fields (PEF). The PEF surround the posterior, medial segment of the intraparietal sulcus. They have a role in reflexive saccades, and send information to the FEF. Since the FEF and PEF have complementary roles in voluntary and reflexive production of saccades, respectively, and they get inputs from different areas of the brain, only bilateral lesions to both the FEF and PEF will cause persistent OMA. Patients with either bilateral FEF or bilateral PEF damage (but not both FEF and PEF) have been shown to regain at least some voluntary saccadic initiation some time after their hemorrhages. Other causes of OMA include brain tumors and cardiovascular problems.