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Assessment will usually include an interview with the child’s caregiver, observation of the child in an unstructured setting, a hearing test, and standardized tests of language and nonverbal ability. There is a wide range of language assessments in English. Some are restricted for use by speech and language professionals (therapists or SALTs in the UK, speech-language pathologists, SLPs, in the US and Australia).
A commonly used test battery for diagnosis of SLI is the Clinical Evaluation of Language Fundamentals (CELF).
Assessments that can be completed by a parent or teacher can be useful to identify children who may require more in-depth evaluation.
The Grammar and Phonology Screening (GAPS) test is a quick (ten minute) simple and accurate screening test developed and standardized in the UK. It is suitable for children from 3;4 to 6;8 years;months and can be administered by professionals and non-professionals (including parents) alike, and has been demonstrated to be highly accurate (98% accuracy) in identifying impaired children who need specialist help vs non-impaired children. This makes it potentially a feasible test for widespread screening.
The Children’s Communication Checklist (CCC–2) is a parent questionnaire suitable for testing language skills in school-aged children.
Informal assessments, such as language samples, may also be used. This procedure is useful when the normative sample of a given test is inappropriate for a given child, for instance, if the child is bilingual and the sample was of monolingual children. It is also an ecologically valid measure of all aspects of language (e.g. semantics, syntax, pragmatics, etc.).
To complete a language sample, the SLP will spend about 15 minutes talking with the child. The sample may be of a conversation (Hadley, 1998), or narrative retell. In a narrative language sample, the SLP will tell the child a story using a wordless picture book (e.g. "Frog Where Are You?", Mayer, 1969), then ask the child to use the pictures and tell the story back.
Language samples are typically transcribed using computer software such as the Systematic Analysis of Language Software (SALT, Miller et al. 2012), and then analyzed. For example, the SLP might look for whether the child introduces characters to their story or jumps right in, whether the events follow a logical order, and whether the narrative includes a main idea or theme and supporting details.
Assessment will usually include an interview with the child’s caregiver, observation of the child in an unstructured setting, a hearing test, and standardized tests of language. There is a wide range of language assessments in English. Some are restricted for use by experts in speech-language pathology: speech and language therapists (SaLTs/SLTs) in the UK, speech-language pathologists (SLPs) in the US and Australia. A commonly used test battery for diagnosis of DLD is the Clinical Evaluation of Language Fundamentals (CELF).
Assessments that can be completed by a parent or teacher can be useful to identify children who may require more in-depth evaluation. The Children’s Communication Checklist (CCC–2) is a parent questionnaire suitable for assessing everyday use of language in children aged 4 years and above who can speak in sentences.
Informal assessments, such as language samples, are often used by speech-language therapists/pathologists to complement formal testing and give an indication of the child's language in a more naturalistic context. A language sample may be of a conversation or narrative retell. In a narrative language sample, an adult may tell the child a story using a wordless picture book (e.g. Frog Where Are You?, Mayer, 1969), then ask the child to use the pictures and tell the story back. Language samples can be transcribed using computer software such as the Systematic Analysis of Language Software, and then analyzed for a range of features: e.g., the grammatical complexity of the child's utterances, whether the child introduces characters to their story or jumps right in, whether the events follow a logical order, and whether the narrative includes a main idea or theme and supporting details.
Developmental Verbal Dyspraxia can be diagnosed by a speech language pathologist (SLP) through specific exams that measure oral mechanisms of speech. The oral mechanisms exam involves tasks such as pursing lips, blowing, licking lips, elevating the tongue, and also involves an examination of the mouth. A complete exam also involves observation of the patient eating and talking. Tests such as the Kaufman Speech Praxis test, a more formal examination, are also used in diagnosis.
A differential diagnosis of DVD/CAS is often not possible for children under the age of 2 years old. Even when children are between 2–3 years, a clear diagnosis cannot always occur, because at this age, they may still be unable to focus on, or cooperate with, diagnostic testing.
1. SCAN is the most common tool for diagnosing APD, and it also standardized. It is composed for four subsets: discrimination of monaurally presented single words against background noise, acoustically degraded single words, dichotically presented single words, sentence stimuli. Different versions of the test are used depending on the age of the patient.
2. Random Gap Detection Test (RGDT) is also a standardized test. It assesses an individual’s gap detection threshold of tones and white noise. The exam includes stimuli at four different frequencies (500, 1000, 2000, and 4000 Hz) and white noise clicks of 50 ms duration. It is a useful test because it provides an index of auditory temporal resolution. In children, an overall gap detection threshold greater than 20 ms means they have failed.
3. Gaps in Noise Test (GIN) also measures temporal resolution by testing the patient's gap detection threshold in white noise.
4. Pitch Patterns Sequence Test (PPT) and Duration Patterns Sequence Test (DPT) measure auditory pattern identification. The PPS has s series of three tones presented at either of two pitches (high or low). Meanwhile, the DPS has a series of three tones that vary in duration rather than pitch (long or short). Patients are then asked to describe the pattern of pitches presented.
Sensory aphasia cannot be diagnosed through the use of imaging techniques. Differences in cognition between asymptomatic subjects and affected patients can be observed via functional magnetic resonance imaging (fMRI). However, these results only reveal temporal differences in cognition between control and diagnosed subjects. The degree of progression during therapy can also be surveyed through cognition tests monitored by fMRI. Many patients’ progress is assessed over time via repeated testing and corresponding cerebral imaging by fMRI.
Epidemiological surveys, in the US and Canada, estimated the prevalence of SLI in 5-year-olds at around 7 percent. However, neither study adopted the stringent 'discrepancy' criteria of the Diagnostic and Statistical Manual of Mental Disorders or ICD-10; SLI was diagnosed if the child scored below cut-off on standardized language tests, but had a nonverbal IQ of 90 or above and no other exclusionary criteria.
DLD is defined purely in behavioural terms: there is no biological test. There are three points that need to be met for a diagnosis of DLD:
1. The child has language difficulties that create obstacles to communication or learning in everyday life,
2. The child's language problems are unlikely to resolve by five years of age, and
3. The problems are not associated with a known biomedical condition such as brain injury, neurodegenerative conditions, genetic conditions or chromosome disorders such as Down Syndrome, sensorineural hearing loss, or Autism Spectrum Disorder or Intellectual Disability.
For research and epidemiological purposes, specific cutoffs on language assessments have been used to document the first criterion. Tomblin et al. proposed the EpiSLI criterion, based on five composite scores representing performance in three domains of language (vocabulary, grammar, and narration) and two modalities (comprehension and production). Children scoring in the lowest 10% on two or more composite scores are identified as having language disorder.
The second criterion, persistence of language problems, can be difficult to judge in a young child, but longitudinal studies have shown that difficulties are less likely to resolve for children who have poor language comprehension, rather than difficulties confined to expressive language. In addition, children with isolated difficulties in just one of the areas noted under 'subtypes' tend to make better progress than those whose language is impaired in several areas.
The third criterion specifies that DLD is used for children whose language disorder is not part of another biomedical condition, such as a genetic syndrome, a sensorineural hearing loss, neurological disease, Autism Spectrum Disorder or Intellectual Disability – these were termed 'differentiating conditions' by the CATALISE panel. Language disorders occurring with these conditions need to be assessed and children offered appropriate intervention, but a terminological distinction is made so that these cases would be diagnosed as Language Disorder associated with ___, with the main diagnosis being specified: e.g. "Language Disorder associated with Autism Spectrum Disorder." The reasoning behind these diagnostic distinctions is discussed further by Bishop (2017).
Sensory aphasia is typically diagnosed by non-invasive evaluations. Neurologists, neuropsychologists or speech pathologists will administer oral evaluations to determine the extent of a patient’s comprehension and speech capability. Initial assessment will determine if the cause of linguistic deficiency is aphasia. If the diagnosis is then confirmed, testing will next address the type of aphasia and its severity. The Boston Diagnostic Aphasia Examination specializes in determining the severity of a sensory aphasia through the observation of conversational behaviors. Several modalities of perception and response are observed in conjunction with the subject’s ability to process sensory information. The location of the brain lesion and type of the aphasia can then be inferred from the observed symptoms. The Minnesota Test for Differential Diagnosis is the most lengthy and thorough assessment of sensory aphasia. It pinpoints weaknesses in the auditory and visual senses, as well as reading comprehension. From this differential diagnosis, a patient’s course of treatment can be determined. After treatment planning, the Porch Index of Communicative Ability is used to evaluate prognosis and the degree of recovery.
"Aphasia is usually first recognized by the physician who treats the person for his or her brain injury. Most individuals will undergo a magnetic resonance imaging (MRI) or computed tomography (CT) scan to confirm the presence of a brain injury and to identify its precise location." In circumstances where a person is showing possible signs of aphasia, the physician will refer him or her to a speech-language pathologist (SLP) for a comprehensive speech and language evaluation. SLPs will examine the individual's ability to express him or herself through speech, understand language in written and spoken forms, write independently, and perform socially.
The American Speech, Language, Hearing Association (ASHA) states a comprehensive assessment should be conducted in order to analyze the patient's communication functioning on multiple levels; as well as the effect of possible communication deficits on activities of daily living. Typical components of an aphasia assessment include: case history, self report, oral-motor examination, language skills, identification of environmental and personal factors, and the assessment results. A comprehensive aphasia assessment includes both formal and informal measures.
Formal assessments:
- Boston Diagnostic Aphasia Examination (BDAE): diagnoses the presence and type of aphasia, focusing on location of lesion and the underlying linguistic processes.
- Western Aphasia Battery - Revised (WAB): determines the presence, severity, and type of aphasia; and can also determine baseline abilities of patient.
- Communication Activities of Daily Living - Second Edition (CADL-2): measures functional communication abilities; focuses on reading, writing, social interactions, and varying levels of communication.
- Revised Token Test (RTT): assess receptive language and auditory comprehension; focuses on patient's ability to follow directions.
Informal Assessments:
Informal assessments aide in the diagnosis of patients with suspected aphasia.
- Conversational Speech and Language Sample
- Family Interview
- Case History or Medical Chart Review
- Behavioral Observations
Diagnostic information should be scored and analyzed appropriately. Treatment plans and individual goals should be developed based on diagnostic information, as well as patient and caregiver needs, desires, and priorities.
It has been discovered that APD and ADHD present overlapping symptoms. Below is a ranked order of behavioral symptoms that are most frequently observed in each disorder. Professionals evaluated the overlap of symptoms between the two disorders. The order below is of symptoms that are almost always observed. This chart proves that although the symptoms listed are different, it is easy to get confused between many of them.
There is a high rate of co-occurrence between AD/HD and CAPD. Research shows that 84% of children with APD have confirmed or suspected ADHD. Co-occurrence between ADHD and APD is 41% for children with confirmed diagnosis of ADHD, and 43% for children suspected of having ADHD.
Another method implemented to test for aprosodia involves having questionnaires filled out by those close to the patient. The doctors and nurses taking care of a patient are also requested to fill out a questionnaire if aprosodia is suspected. This diagnosis method occurs more as an indicator that the aprosodia battery should be administered rather than being used as a singular diagnosis tool. Implementation of the questionnaire is expected to become more widespread as aprosodia is revealed to be a side-effect of more diseases.
TMoA is diagnosed by the referring physician and speech-language pathologist (SLP). The overall sign of TMoA is nonfluent, reduced, fragmentary echoic, and perseverative speech with frequent hesitations and pauses. Patients with TMoA also have difficulty initiating and maintaining speech. However, speech articulation and auditory comprehension remain typical. The hallmark sign of TMoA is intact repetition in the presence of these signs and symptoms.
TMoA, or any other type of aphasia, is identified and diagnosed through the screening and assessment process. Screening can be conducted by a SLP or other professional when there is a suspected aphasia. The screening does not diagnose aphasia, rather it points to the need for a further comprehensive assessment. A screening typically includes evaluation of oral motor functions, speech production skills, comprehension, use of written and verbal language, cognitive communication, swallowing, and hearing. Both the screening and assessment must be sensitive to the patient’s linguistic and cultural differences. An individual will be recommended to receive a comprehensive assessment if their screening shows signs of aphasia. Under the American Speech-Language-Hearing Association (ASHA) and World Health Organization (WHO) guidelines and the "International Classification of Functioning, Disability and Health" (ICF) framework, the comprehensive assessment encompasses not only speech and language, but also impairments in body structure and function, co-morbid deficits, limitations in activity and participation, and contextual (environmental and personal) factors. The assessment can be static (current functioning) or dynamic (ongoing) and the assessment tools can be standardized or nonstandardized. Typically, the assessment for aphasia includes a gathering of a case history, a self-report from the patient, an oral-motor examination, assessment of expressive and receptive language in spoken and written forms, and identification of facilitators and barriers to patient success. From this assessment, the SLP will determine type of aphasia and the patient's communicative strengths and weaknesses and how their diagnosis may impact their overall quality of life.
The best way to see if anomic aphasia has developed is by using verbal as well as imaging tests. The combination of the two tests seem to be most effective, since either test done alone may give false positives or false negatives. For example, the verbal test is used to see if there is a speech disorder, and whether it is a problem in speech production or in comprehension. Patients with Alzheimer's disease have speech problems that are linked to dementia or progressive aphasias which can include anomia. The imaging test, mostly done using MRI scans, is ideal for lesion mapping or viewing deterioration in the brain. However, imaging cannot diagnose anomia on its own because the lesions may not be located deep enough to damage the white matter or damage the arcuate fasciculus. However, anomic aphasia is very difficult to associate with a specific lesion location in the brain. Therefore, the combination of speech tests and imaging tests has the highest sensitivity and specificity.
It is important to first do a hearing test, in case the patient cannot clearly hear the words or sentences needed in the speech repetition test. In the speech tests, the person is asked to repeat a sentence with common words; if the person cannot identify the word but he or she can describe it, then the person is highly likely to have anomic aphasia. However, to be completely sure, the test is given while a test subject is in an fMRI scanner, and the exact location of the lesions and areas activated by speech are pinpointed. Few simpler or cheaper options are available, so lesion mapping and speech repetition tests are the main ways of diagnosing anomic aphasia.
Individuals with conduction aphasia are able to express themselves fairly well, with some word finding and functional comprehension difficulty. Although people with aphasia may be able to express themselves fairly well, they tend to have issues repeating phrases, especially phrases that are long and complex. When asked to repeat something, the patient will be unable to do so without significant difficulty, repeatedly attempting to self-correct ("conduite d'approche"). When asked a question, however, patients can answer spontaneously and fluently.
Several standardized test batteries exist for diagnosing and classifying aphasias. These tests are capable of identifying conduction aphasia with relative accuracy. The Boston Diagnostic Aphasia Examination (BDAE) and the Western Aphasia Battery (WAB) are two commonly used test batteries for diagnosing conduction aphasia. These examinations involve a set of tests, which include asking patients to name pictures, read printed words, count aloud, and repeat words and non-words (such as "shwazel").
Expressive aphasia is classified as non-fluent aphasia, as opposed to fluent aphasia. Diagnosis is done on a case by case basis, as lesions often affect the surrounding cortex and deficits are highly variable among patients with aphasia.
A physician is typically the first person to recognize aphasia in a patient who is being treated for damage to the brain. Routine processes for determining the presence and location of lesion in the brain include Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) scans. The physician will complete a brief assessment of the patient's ability to understand and produce language. For further diagnostic testing, the physician will refer the patient to a speech-language pathologist, who will complete a comprehensive evaluation.
In order to diagnose a patient who is suffering from Broca’s aphasia, there are certain commonly used tests and procedures. The Western Aphasia Battery (WAB) classifies individuals based on their scores on the subtests; spontaneous speech, auditory comprehension, repetition, and naming. The Boston Diagnostic Aphasia Examination (BDAE) can inform users what specific type of aphasia they may have, infer the location of lesion, and assess current language abilities. The Porch Index of Communication Ability (PICA) can predict potential recovery outcomes of the patients with aphasia. Quality of life measurement is also an important assessment tool. Tests such as the Assessment for Living with Aphasia (ALA) and the Satisfaction with Life Scale (SWLS) allow for therapists to target skills that are important and meaningful for the individual.
In addition to formal assessments, patient and family interviews are valid and important sources of information. The patient’s previous hobbies, interests, personality, and occupation are all factors that will not only impact therapy but may motivate them throughout the recovery process. Patient interviews and observations allow professionals to learn the priorities of the patient and family and determine what the patient hopes to regain in therapy. Observations of the patient may also be beneficial to determine where to begin treatment. The current behaviors and interactions of the patient will provide the therapist with more insight about the client and his or her individual needs. Other information about the patient can be retrieved from medical records, patient referrals from physicians, and the nursing staff.
In non-speaking patients who use manual languages, diagnosis is often based on interviews from the patient's acquaintances, noting the differences in sign production pre- and post- damage to the brain. Many of these patients will also begin to rely on non-linguistic gestures to communicate, rather than signing since their language production is hindered.
Assessments for developmental coordination disorder typically require a developmental history, detailing ages at which significant developmental milestones, such as crawling and walking, occurred. Motor skills screening includes activities designed to indicate developmental coordination disorder, including balancing, physical sequencing, touch sensitivity, and variations on walking activities.
The American Psychiatric Association has four primary inclusive diagnostic criteria for determining if a child has developmental coordination disorder.
The criteria are as follows:
1. Motor Coordination will be greatly reduced, although the intelligence of the child is normal for the age.
2. The difficulties the child experiences with motor coordination or planning interfere with the child's daily life.
3. The difficulties with coordination are not due to any other medical condition
4. If the child does also experience comorbidities such as mental retardation; motor coordination is still disproportionally affected.
Screening tests which can be used to assess developmental coordination disorder include:-
- Movement Assessment Battery for Children (Movement-ABC – Movement-ABC 2)
- Peabody Developmental Motor Scales- Second Edition (PDMS-2)
- Bruininks-Oseretsky Test of Motor Proficiency (BOTMP-BOT-2)
- Motoriktest für vier- bis sechsjährige Kinder (MOT 4-6)
- Körperkoordinationtest für Kinder (KTK)
- Test of Gross Motor Development, Second Edition (TGMD-2)
- Maastrichtse Motoriek Test (MMT)
- Wechsler Adult Intelligence Scale (WAIS-IV)
- Wechsler Individual Achievement Test (WAIT-II)
- Test of Word Reading Efficiency (TOWRE-2)
- Developmental Coordination Disorder Questionnaire (DCD-Q)
- Children's Self-Perceptions of Adequacy in, and Predilection for Physical Activity (CSAPPA)
Currently there is no single gold standard assessment test.
A baseline motor assessment establishes the starting point for developmental intervention programs. Comparing children to normal rates of development may help to establish areas of significant difficulty.
However, research in the "British Journal of Special Education" has shown that knowledge is severely limited in many who should be trained to recognise and respond to various difficulties, including developmental coordination disorder, dyslexia and deficits in attention, motor control and perception (DAMP). The earlier that difficulties are noted and timely assessments occur, the quicker intervention can begin. A teacher or GP could miss a diagnosis if they are only applying a cursory knowledge.
"Teachers will not be able to recognise or accommodate the child with learning difficulties in class if their knowledge is limited. Similarly GPs will find it difficult to detect and appropriately refer children with learning difficulties."
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.
Classifying speech into normal and disordered is more problematic than it first seems. By a strict classification, only 5% to 10% of the population has a completely normal manner of speaking (with respect to all parameters) and healthy voice; all others suffer from one disorder or another.
There are three different levels of classification when determining the magnitude and type of a speech disorders and the proper treatment or therapy:
1. Sounds the patient can produce
1. Phonemic – can be produced easily; used meaningfully and constructively
2. Phonetic – produced only upon request; not used consistently, meaningfully, or constructively; not used in connected speech
2. Stimulate sounds
1. Easily stimulated
2. Stimulate after demonstration and probing (i.e. with a tongue depressor)
3. Cannot produce the sound
1. Cannot be produced voluntarily
2. No production ever observed
There are tests that can indicate with high probability whether a person is a dyslexic. If diagnostic testing indicates that a person may be dyslexic, such tests are often followed up with a full diagnostic assessment to determine the extent and nature of the disorder. Tests can be administered by a teacher or computer. Some test results indicate how to carry out teaching strategies.
In 2006, the U.S. Department of Education indicated that more than 1.4 million students were served in the public schools' special education programs under the speech or language impairment category of IDEA 2004. This estimate does not include children who have speech/language problems secondary to other conditions such as deafness; this means that if all cases of speech or language impairments were included in the estimates, this category of impairment would be the largest. Another source has estimated that communication disorders—a larger category, which also includes hearing disorders—affect one of every 10 people in the United States.
ASHA has cited that 24.1% of children in school in the fall of 2003 received services for speech or language disorders—this amounts to a total of 1,460,583 children between 3 –21 years of age. Again, this estimate does not include children who have speech/language problems secondary to other conditions. Additional ASHA prevalence figures have suggested the following:
- Stuttering affects approximately 4% to 5% of children between the ages of 2 and 4.
- ASHA has indicated that in 2006:
- Almost 69% of SLPs served individuals with fluency problems.
- Almost 29% of SLPs served individuals with voice or resonance disorders.
- Approximately 61% of speech-language pathologists in schools indicated that they served individuals with SLI
- Almost 91% of SLPs in schools indicated that they servedindividuals with phonological/articulation disorder
- Estimates for language difficulty in preschool children range from 2% to 19%.
- Specific Language Impairment (SLI) is extremely common in children, and affects about 7% of the childhood population.
In most cases the cause is unknown. However, there are various known causes of speech impediments, such as "hearing loss, neurological disorders, brain injury, intellectual disability, drug abuse, physical impairments such as cleft lip and palate, and vocal abuse or misuse."
Apraxia of speech can be diagnosed by a speech language pathologist (SLP) through specific exams that measure oral mechanisms of speech. The oral mechanisms exam involves tasks such as pursing lips, blowing, licking lips, elevating the tongue, and also involves an examination of the mouth. A complete exam also involves observation of the patient eating and talking. SLPs do not agree on a specific set of characteristics that make up the apraxia of speech diagnosis, so any of the characteristics from the section above could be used to form a diagnosis. Patients may be asked to perform other daily tasks such as reading, writing, and conversing with others. In situations involving brain damage, an MRI brain scan also helps identify damaged areas of the brain.
A differential diagnosis must be used in order to rule out other similar or alternative disorders. Although disorders such as expressive aphasia, conduction aphasia, and dysarthria involve similar symptoms as apraxia of speech, the disorders must be distinguished in order to correctly treat the patients. While AOS involves the motor planning or processing stage of speech, aphasic disorders can involve other language processes.
According to Ziegler et al., this difficulty in diagnosis derives from the unknown causes and function of the disorder, making it hard to set definite parameters for AOS identification. Specifically, he explains that oral-facial apraxia, dysarthria, and aphasic phonological impairment are the three distinctly different disorders that cause individuals to display symptoms that are often similar to those of someone with AOS, and that these close relatives must be correctly ruled out by a Speech Language Pathologist before AOS can be given as a diagnosis. In this way, AOS is a diagnosis of exclusion, and is generally recognized when all other similar speech sound production disorders are eliminated.
Dyslexic children require special instruction for word analysis and spelling from an early age. While there are fonts that may help people with dyslexia better understand writing, this might simply be due to the added spacing between words. The prognosis, generally speaking, is positive for individuals who are identified in childhood and receive support from friends and family.
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 relation to other types of aphasia, TMoA occurs less frequently, so there is less information on its prognosis. In general, for individuals with aphasia, most recovery is seen within 6 months of the stroke or injury although more recovery may continue in the following months or years. The timeline of recovery may look different depending on the type of stroke that caused the aphasia. With an ischemic stroke, recovery is greatest within the first two weeks and then diminishes overtime until the progress stabilizes. With a hemorrhagic stroke, the patient often shows little improvement in the first few weeks and then has relatively rapid recovery until they stabilize.
In a study involving eight patients with border zone lesions, all patients presented with transcortical mixed aphasia initially after the stroke. Three of these patients made a complete recovery within a few days post-stroke. For three other patients with more anterior lesions, their aphasia transitioned to TMoA. All participants in the study regained full language abilities within 18 months following their stroke. This suggests a positive long-term prognosis for patients with TMoA. However, this might not be the case for all patients and more research is needed in order to solidify these findings. Another study found that prognosis of TMoA is affected by lesion size. Smaller lesions typically cause delays in speech initiation; whereas, larger lesions lead to more profound language abnormalities and difficulty with abstract language abilities.
Research has shown that treatment has a direct effect on aphasia outcomes. Intensity, duration and timing of treatment all need to be taken in to consideration when choosing a course of treatment and determining a prognosis. In general, greater intensity leads to greater improvement. For duration, longer-term treatment produces more permanent changes. As for timing, beginning treatment too early may be difficult for the system which has not recovered enough to do intensive therapy, but beginning too late may result missing the window of the opportunity in which the most change can occur. Neuroplasticity, the brain's natural ability to reorganize itself following a traumatic event, occurs best when treatment connects simultaneous events, maintains attention, taps into positive emotion, utilizes repetition tasks, and is specific to the individual's needs.
Other factors affecting prognosis includes location and site of lesion. Since the lesion that results in TMoA usually occurs in the watershed area and does not directly involve the areas of the brain responsible for general language abilities, prognosis for these patients is good overall. Other factors that determine a patient’s prognosis include age, education prior to the stroke, gender, motivation, and support.