ICCD 2016 ICCD Iowa Conference on Communicative Disorders Cedar Falls, Iowa [DIFFERENTIAL DIAGNOSIS OF MOTOR SPEECH DISORDERS] Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016 Motor Speech Disorders The evolution of a classification system Prior to the classification system first introduced by Darley, Aronson, & Brown (1969), the dysarthrias were considered a single diagnosis. The implication was that this diagnosis had homogeneous features. Distinctions were made between dysarthria and aphasia, even dysarthria and apraxia of speech. Parallels Autism No longer really considered a unitary diagnosis Autism spectrum • Further definition Asberger’s Syndrome Differential diagnosis Evolution of a discipline A need to better understand and define clinical populations. Evaluation More accurate diagnosis Treatment Guide our treatment decisions Darley, Aronson, & Brown Pivotal articles (1969) “Motor Speech Disorders” text (1975) Defined and identified the dysarthrias Initial sample = 212 patients Lesion site Perceptual characteristics Motor characteristics Benefits & Drawbacks Assists with confirmation of lesion site Can rule out other potential diagnoses Clinical “shorthand” Similar to aphasia syndromes Guides treatment decisions Julie A.G. Stierwalt, Ph.D. Mayo Clinic Page 2 Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016 Understanding the underlying pathology results in selecting the appropriate treatment Reliability has been questioned Corresponding lesion data Clinical knowledge Not confirmed empirically Take home message… Clinically useful Evolution continues Our understanding of neuropathology will never be static New discoveries New procedures For now, the system is a useful one that will continue to be refined Hyperkinetic Myriad of movement disorders The Dysarthrias “A collective name for a group of neurologic speech disorders resulting from abnormalities in the strength, speed, range, steadiness, tone, or accuracy of movements required for control of the respiratory, phonatory, resonatory, articulatory, and prosodic aspects of speech production. The responsible pathophysiologic disturbances are due to central or peripheral nervous system abnormalities and most often reflect weakness; spasticity; incoordination; involuntary movements; or excessive, reduced or variable muscle tone.” (Duffy, 2013 p. 4) Prevalence of MSD Based on a sample > 14, 000 people referred for a speech/language evaluation at Mayo Clinic from 1993-2008 Other neurologic speech disorders - 0.4% Apraxia of Speech – 3.9% Nonaphasic cognitive-communication disorders – 16.8 % Aphasia – 25.8% Dysarthria – 53% Julie A.G. Stierwalt, Ph.D. Mayo Clinic Page 3 Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016 Definition revisited: Key features of the dysarthrias Neurologic basis Disorder of movement Categorized based on Lesion Physical characteristics (OME findings) Speech characteristics DYSARTHRIA Lesion Physical signs Speech FLACCID SPASTIC ATAXIC HYPOKINETIC HYPERKINETIC MIXED Julie A.G. Stierwalt, Ph.D. Mayo Clinic Page 4 Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016 Flaccid Dysarthria Results from injury/damage to cranial and/or spinal nerves Final common pathway Lower motor neuron Reflexive, automatic, and voluntary activities are ALL affected when the lesion resides in the FCP. Can impact all subsystems of speech Primary characteristics can be traced to weakness Which of the Cranial and/or spinal nerves might be implicated? • Etiologies Surgical Nonsurgical Neuropathies Tumor/Neoplasm Myasthenia gravis Degenerative Vascular Anatomic malformation Demyelinating Other Lesion analysis • Trigeminal Innervation properties Three branches (sensory) Motor component • Signs Sensory loss Jaw deviation (unilateral) Jaw may hang open (bilateral) • How do you test? • Speech signs Imprecision in connected speech Most affected with bilateral lesions • Facial Innervation properties Sensory Motor Which would be most devastating to speech? Signs Facial droop Drooling (possibly) Pocketing Testing • • Julie A.G. Stierwalt, Ph.D. Mayo Clinic Page 5 Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016 • Speech signs Imprecision in connected speech Related to facial weakness What sounds would be most affected? • Glossopharyngeal Innervation properties Sensory Motor Signs Testing Speech signs • Vagus Innervation properties Sensory Motor Signs Velar signs Testing Speech signs Phonation Respiration Resonance • Spinal Accessory Innervation properties Motor Signs Shoulder weakness Testing Speech signs • Hypoglossal Innervation properties Motor Signs Tongue deviation Atrophy Testing Speech signs Imprecision with articulation Compensation with the mandible • Spinal nerve lesions Julie A.G. Stierwalt, Ph.D. Mayo Clinic Page 6 Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016 Damage to spinal nerves C-1 through C-5 Primary damage to respiration How does that interfere with speech? Signs Rapid/shallow breathing Exaggerated thoracic expansion Flaccid dysarthria related to isolated damage to spinal nerve lesions is rare Primary Characteristics • Weakness • Hypotonia and reduced reflexes • Fasciculations and fibrillations Darley, Aronson & Brown (1969) Hypernasality Articulatory Imprecision Breathiness Monopitch VPI Audible inspiration Harsh vocal quality Short phrases Monoloudness *********************************************************************************** Spastic Dysarthria Secondary to damage of the direct and indirect pathways of the CNS (UMN system) Direct pathway Pyramidal tract Corticobulbar tracts Interacts with cranial nerves Corticospinal tracts Interacts with spinal nerves Facilitatory action Leads to skilled discrete movements Indirect pathway Extramyramidal Regulates reflexes, maintains posture, tone Inhibatory nature Clinical Characteristics Difficulty with fine, discrete movements Initially decreased tone Julie A.G. Stierwalt, Ph.D. Mayo Clinic Page 7 Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016 Weakness Develops into increased tone, spasticity Those muscles utilized in fine movements most affected Decreased reflexes initially, then more pronounced Babinski sign Oral motor reflexes Suck Snout Jaw jerk Etiologies Vascular Brainstem stroke Bilateral effects Cerebral stroke can’t have the same impact, unless there is previous damage, or perhaps midline shift/compression from a hemorrhagic stroke Lacunar infarcts Multi-infarct dementia Not a common problem with DAT Inflammatory Leukoencephalitis Degenerative disease Primary lateral sclerosis Traumatic Brain Injury Multiple Sclerosis Neoplasm Oral Mechanism Dysphagia Drooling Pseudobulbar affect Normal jaw strength Facial movements may be slow then move into excess/extreme Hyperactive reflexes Speech Characteristics Impairments noticed most by looking at muscle movement rather than isolated muscles •« speed •«range •«force •ªmuscle tone Darley, Aronson, & Brown (1969a) Imprecise artic Monopitch Julie A.G. Stierwalt, Ph.D. Mayo Clinic Page 8 Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016 •« stress Harshness Monoloudness Low pitch Slow rate Hypernasality Strained-strangled quality Short phrases Distorted vowels Pitch breaks Breathy quality Excess and equal stress *********************************************************************************** Ataxic Dysarthria Cerebellum Two cerebellar hemispheres Vermis Ipsilateral contribution Unlike the cerebral hemispheres which have contralateral contributions With median lesions, effects may be bilateral How does the “circuit” function? The “circuit” Notice of movement-cerebral hemispheres Monitors the movement via feedback from the muscles/joints that conduct the movement. Regulates movement in an ongoing fashion based on both ends of this circuit. Clinical Characteristics Ataxic dysarthria typically manifests with diffuse cerebellar damage Any signs/symptoms from unilateral lesions tend to improve rapidly Disordered gait Truncal instability, titubation Rotated head postures Occular motor abnormalities Ataxic dysarthria Etiologies Degenerative Diseases Hereditary Ataxias Multiple Sclerosis Paroxysmal Ataxic Dysarthria Vascular Disorders Julie A.G. Stierwalt, Ph.D. Mayo Clinic Page 9 Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016 Aneurysms AVMs Occlusion in the vertebrobasilar system Neoplasm Trauma Toxic/metabolic conditions Alcoholic cerebellar degeneration Severe malnutrition Vitamin deficiencies Pharmacological Antiseizure drugs Lithium Valium Hypothyroidism Normal Pressure Hydrocephalus Oral Mechanism Most aspects of the OME can be entirely normal Size Strength Symmetry Face, jaw, tongue, palate Rest, and during sustained postures Gag Reflexive swallow OME abnormalities Irregular AMRs Observe the regularity of movement of the tongue, lips, and jaw AMRs and connected speech Systemic problem Affects the entire system rather than isolated impairment from muscles/muscle groups Speech Imprecision with artic Irregular artic breakdown Distorted vowels Excess and/or equal stress Prolonged phonemes/pauses Slow rate Harshness Monopitch Monoloudness Reduced/irregular breathgroups Darley, Aronson, & Brown 1969 Artic imprecision Julie A.G. Stierwalt, Ph.D. Mayo Clinic Page 10 Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016 Excess/equal stress Irregular artic breakdowns Distorted vowels Harsh quality Prolonged phonemes Prolonged intervals Monopitch Monoloudness Slow rate Loudness variations Voice tremor *********************************************************************************** Hypokinetic Dysarthria • Pathology of the basal ganglia control circuit – Rigidity – Reduced force/range • Decreased mobility a/o range lead to the name “hypokinetic” • The only dysarthria which has “rapid” speech rate as one of the perceptual characteristics. • Depletion or reduction of the neurotransmitter, dopamine. • Parkinson’s disease that best reflects hypokinetic dysarthria. • Basal Ganglia Control Circuit – Functions • Regulate muscle tone • Movements that support goal directed activity • Postural adjustments • Adjust movements to the environment • Assists in learning new movements • Damage results in reduced movement a/o a failure to inhibit involuntary movement • Hypokinetic dysarthria most reflects reduced movement Clinical Characteristics • Resting tremor Julie A.G. Stierwalt, Ph.D. Mayo Clinic Page 11 Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016 • • – – – – 4-7 Hz Limbs Pill-rolling Jaw, lips, and tongue Rigidity – Resistance to passive stretch – Decreased movement Bradykinesia/Akinesia – Slow movement – Freezing – Shuffling gait – Micrographia – Masked facies – Reduction in: • Arm movement while walking • Gestures • Blinking • Head movement • Swallowing frequency • Loss of postural reflexes – Reduced “righting” response – Stooped posture – Difficulty initiating movment • While lying down • Sitting to standing Etiologies • Damage to the basal ganglia – Degenerative – Vascular – Traumatic – Inflammatory – Neoplastic – Toxic – Metabolic diseases Oral Mechanism • Immediate revealing features Julie A.G. Stierwalt, Ph.D. Mayo Clinic Page 12 Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016 – Masked facies • Flat affect – Respiratory signs – Infrequent swallowing • May result in drooling – Size, strength, and symmetry may be normal – AMRs may be slowly initiated a/o rapid and restricted in range Speech Characteristics • Monopitch • Monoloudness – Reduced intensity – Breathy quality • Reduced stress • Short phrases • Variable rate • Short rushes of speech • Imprecise consonants *********************************************************************************** Hyperkinetic Dysarthria • Another dysarthria type that manifests secondary to damage to the basal ganglia control circuit • May effect all or isolated speech subsystems. • Involuntary movement is the hallmark feature – Rhythmic – Irregular – Fast – slow Abnormal • What constitutes abnormal? • Involuntary movements when steadiness is expected Julie A.G. Stierwalt, Ph.D. Mayo Clinic Page 13 Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016 • Hyper-in this case does not mean fast – Excessive, extra • Many forms • Classified based on speed and periodicity Classification • Dyskinesia • Myoclonus • Tics • Chorea • Ballism • Athetosis • Dystonia • Spasm • Tremor Etiologies • Degenerative • Vascular • Traumatic • Inflammatory • Toxic • Metabolic disease *********************************************************************************** Mixed Dysarthrias • Mixed dysarthrias – Combination of dysarthrias • Two or more • Diffuse damage • Etiologies Julie A.G. Stierwalt, Ph.D. Mayo Clinic Page 14 Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016 – Degenerative • ALS • MS • PSP – Toxic metabolic • Wilson’s disease • Hepatocerebral degeneration • Hypoxic encephalopathy – Vascular Disorders – Trauma – Neoplasm – Infectious diseases *********************************************************************************** Apraxia of Speech “A neurologic speech disorder that reflexts an impaired capacity to plan or program sensorimotor commands necessary for directing movements that result in honetically and prosodically normal speech. It can occur in the absence of physiologic disturbances associated with the dysarthrias and in the agsence of disturbance in any component of language.” (Duffy, 2013, p. 4) • Apraxia of speech is secondary to a disturbance of the motor programming system. – Central impairment – Can occur without muscle impairment – Normal function is apparent • High variability • The motor speech programmer executes the motor movements/sequences necessary to convey language – Speech ‘vs’ Language • Primarily left hemisphere lesions – Motor speech area – Brocca’s area – Supplementary motor cortex – Insula • Variability in lesion locations Julie A.G. Stierwalt, Ph.D. Mayo Clinic Page 15 Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016 – Dronkers, 1993 Etiologies • AOS is secondary to primarily focal lesions – vascular – Tumors – Focal/discrete trauma • Surgical • Other • Degenerative conditions – Occasionally have focal effects Clinical Characteristics • May exhibit right sided weakness – May also have sensory deficits • Hyperactive reflexes • Limb apraxia • Concomitant aphasia – Brocca’s type • Can exist in a “pure” form – Few documented cases Assessment findings • Oral mechanism – May have rt. weakness • May result in dysarthria that is not the same as AOS – Nonverbal oral motor apraxia • Difficulty performing oral tasks. – Sequential AMRs • Most sensitive task to the effects of AOS. Specific Speech Characteristics • Slow rate • Prolonged consonants/vowels • Many pauses Julie A.G. Stierwalt, Ph.D. Mayo Clinic Page 16 Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016 – Inter/intrasegmental • Disruptions in prosody • Equal stress • Decreased pitch/intonation contours • False starts • Effortful/laborious speech • Repetitions *********************************************************************************** Factors that influence speech production Injurious Falls Walking One-third of Americans aged 65+ fall each year. Every 14 seconds, an older adult is treated in the E.R. for a fall, every 29 minutes an older adult dies after a fall. Annually, falls result in more than 2.4 million injuries in emergency departments, resulting in over 772,000 hospitalizations and over 21,700 deaths. In 2012, the costs related to falls was over $36 billion, with an expectation to reach over 59 billion annually by 2020. Aging Affects gait patterns Change in skeletal structure Reduced muscle mass/strength Results in a higher incidence of neuropathology. Often with deleterious cognitive and motor effects. Increasing incidence of falls Fear of falling Multitasking Bombarded today by competing stimuli Cell phones Talking or texting Music Environment Walking while talking Sharing tasks may become more difficult when systems become compromised. Julie A.G. Stierwalt, Ph.D. Mayo Clinic Page 17 Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016 Statement of the Problem Injurious falls are a major medical concern. Individuals with neurologic compromise may be at a greater risk. There are known factors that contribute to fall risk. Physical decline Cognitive decline Pharmacological effects Environmental factors What other factors may be influential? Cognitive load… GAITRite™ System Analysis of gait conducted using the GAITRite™ System 14’ portable carpet 16,128 embedded sensors to capture footfalls instantly Measures include temporal and spatial parameters Procedures Each of the groups completed the following: Montreal Cognitive Assessment Beck Depression Index Gait Measures Baseline (walking, no talking) Low load (counting by ones) Medium load (subtracting by 3s) Originating number varied/attempt High load (alpha-numeric sequence) D-7, E-8, F-9… Gait conditions were counterbalanced to account for order effect. Each walk was completed twice to control for learning The average was used for analysis. Dependent measures Functional ambulation profile (FAP) Julie A.G. Stierwalt, Ph.D. Mayo Clinic Page 18 Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016 Ratio of step length to leg length to step time; FAP score is derived from a formula that includes several critical gait parameters found to be highly related to fall risk. (Nelson et. al, 1999) Velocity Centimeters/second Stride length Centimeters Double support time The percentage of time per ambulation cycle with both feet on the ground. Parkinson and Healthy Elderly Twenty six participants with Parkinson Disease: Peak medication time Age: Mean = 67.44 (41-91) Hoehn & Yahr Stage: 22-Stage 2, 3-Stage 3, 1-Stage 4 Thirteen healthy elderly participants Age: Mean – 68.07 Matched for education level No significant differences across groups Stride length or Velocity Data were collapsed and a condition effect was revealed Baseline > High load A significant difference and interaction was revealed for Double Support The healthy adult group significantly increased their Double Support time The group with PD did not High vs. Low Medication State We recruited the same twenty six participants several months later. We asked that they be within 30 minutes of their next medication administration. The same procedures were followed, and we added the Functional Ambulation Profile (FAP) score as a predictor of fall risk. No differences between conditions or High/Low medication states Step velocity Step length Double support FAP Julie A.G. Stierwalt, Ph.D. Mayo Clinic Page 19 Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016 Dopaminergic replacement medication did not alleviate the effect of cognitive load. These results were shared at the World Congress on Parkinson Disease in Paris 2009 Current Study A double blind, randomized control study to investigate the effects of cognitive enhancing medication on performance in individuals with Parkinson disease. Participants were randomly assigned to a drug (Rasagiline vs. Placebo). After 30 days, participants received an increased dose Participants receiving Rasagiline were given a higher dosage for the next 30 days. Participants receiving the placebo received additional placebo tablets. Prior to taking the drug, baseline measures were collected on all experimental tasks (Pre-treatment). Gait Additional measures After 60 days, final data collection occurred (Post-treatment). Gait Additional measures Walking while talking Individuals with neurological compromise are at an increased risk for falls during the multitask of talking while walking. Automatic speech doesn’t carry as great a risk. Increased cognitive load will have deleterious effects especially in high fall risk conditions Low light Descending stairs Giving directions Mental calculations Tracking conditions Obstacles Environmental variations Julie A.G. Stierwalt, Ph.D. Mayo Clinic Page 20 Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016 Cranial Nerve Information Sheet Cranial Nerve I – Olfactory Type Function Sensory Smell II – Optic Sensory Vision III - Oculomotor Motor Eye movement IV - Trochlear Motor Eye movement (superior oblique) Facial sensation – 3 branches Sensory V - Trigeminal VI - Abducens Opthalamic Maxillary Mandibular Anterior tongue sensation Motor Muscles of mastication Motor Eye Movement - lateral rectus Sensory Taste - anterior 2/3 tongue Motor Facial expression VII - Facial Hearing VIII - Vestibulocochlear Sensory Balance Sensory Pharyngeal sensation Motor Pharyngeal muscles Sensory Pharynx, larynx, esophagus Motor Muscles of palate, pharynx, and larynx Motor Shoulder, head movement IX - Glossopharyngeal X - Vagus XI- Spinal Accessory Julie A.G. Stierwalt, Ph.D. Mayo Clinic Page 21 Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016 XII - Hypoglossal Motor Tongue movement For the purpose of screening, the functions listed above are the primary functions of the cranial nerves. This is not meant to serve as an exhaustive list of cranial nerve functions. © Stierwalt, J.A.G., (2003) Cranial Nerve Information Sheet Julie A.G. Stierwalt, Ph.D. Mayo Clinic Page 22 Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016 Cranial Nerve Screening Cranial Nerve Function Screening Task I – Olfactory Sensory - Smell odors II – Optic Sensory - Vision vision chart/acuity III- Oculomotor Motor – Eye movement "follow the moving finger" IV - Trochlear Motor – Eye movement (superior oblique) look at the nose V - Trigeminal Sensory - facial sensation/anterior tongue Have the individual close their eyes: touch the face Motor - muscles of mastication Palpate muscles that clench the teeth VI - Abducens Motor - lateral rectus look to the side VII - Facial Sensory - taste sweet, sour, bitter, salt Motor - facial expression smile, raise the eyebrows Sensory - hearing a tuning fork balance look for vertigo Sensory - pharynx sensation gag reflex Motor – pharyngeal muscles gag reflex Sensory –pharynx, larynx, esophagus Check phonation VIII Vestibulocochlear IX - Glossopharyngeal X - Vagus Julie A.G. Stierwalt, Ph.D. Mayo Clinic Assess vocal quality Page 23 Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016 Motor - muscles of palate, pharynx, and larynx XI- Spinal Accessory Motor – Shoulder, head movement shoulder shrug and/or turning the head to resistance XII - Hypoglossal Motor - tongue movement Assess tongue movement © 2003 Julie A.G. Stierwalt, Ph.D. Bibliography Ball, L. J., Bernthal, J. E., & Beukelman, D. R. (2002). Profiling communication characteristics of children with developmental apraxia of speech. Journal of Medical Speech-Language Pathology, 10, 221-230. Ball, L. J., Beukelman, D. R., & Pattee, G. L. (2002). Timing of speech deterioration in people with amyotrophic lateral sclerosis. Journal of Medical Speech-Language Pathology, 10, 231-236. Barkmeier, J., Jordan, L. S., Robin, D. A., & Schum, R. L. (1991). Inexperienced Listener Ratings of Dysarthric Speaker intelligibility and Physical Appearance. In C. A. 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