Right Hemisphere Disorder ACD FINAL PDF

RIGHT HEMISPHERE DISORDER Left hemisphere - Consider the unique flower of human evolution - Broca and Wernicke’s discoveries led to centuries of exploration of left hemisphere abilities Right hemisphere - Considered subordinate, minor, unconscious - Largely ignored until advent...

RIGHT HEMISPHERE DISORDER Left hemisphere - Consider the unique flower of human evolution - Broca and Wernicke’s discoveries led to centuries of exploration of left hemisphere abilities Right hemisphere - Considered subordinate, minor, unconscious - Largely ignored until advent of corpus commissurotomy in 1960s - Corpus commissurotomy - cutting of corpus callosum to relieve seizures - Allowed the study of each cerebral hemisphere’s independent functions Normal right hemisphere functions - Nonlinguistic elements of communication - Prosody - suprasegmental melody - Facial expression - Body language - Emotion - The patient's grammar, articulation, and understanding is good but something is missing - Math/Visuospatial skills - Perception of depth, distance, shaped - Brain creates depth not the eyes - Localizing targets in space - Identifying figure ground relationships - This is true for people who are left hemisphere dominant in language which is often seen in right handed people and some left handed people - Processing melody of music occurs mainly in right hemisphere - Assembling small details for perception of a larger picture - macrostructure/gestalt - Ability to see and understand the bigger picture Right hemisphere disorders - Group of deficits or changes that may occur following insult to a person’s right cerebral hemispheres - will not have aphasia but different communication disorder - cognitive communication disorders - Usually not involved with language related deficits - Right hemisphere strokes may leave intact functional language abilities if left hemisphere is untouched - However, powerful nonlinguistic cues processed in the right hemisphere are necessary for social pragmatic communication abilities - language use Etiology of right hemisphere disorders - Most common - Stroke - can occur in one hemisphere - Seizure disorders - start primarily in right temporal lobe - Other etiologies - Disease - Trauma - Infection  - Toxicity - Level of deficit or disorder depends on the location and extent of damage - Ex: a small focal stroke may produce isolated deficits while a large stroke may produce deficits across all arenas of cognition Communication deficits of right hemisphere disorders - Manifest themselves in the realm of pragmatics - Areas of deficit which affect communication include - Facial recognition - facial blindness - Comprehension of facial expressions - Production of facial expressions - Comprehension of prosody - Production of prosody - Inferencing - Discourse - Able to recognize the person they are communicating with - able to describe details, no visions problems, cannot understand the bigger picture - hard for them to see and understand facial harmony Facial recognition - Prosopagnosia - Ability to process visual information of facial features and spatial relationships is a refined skill that can be lost - Visual agnosia is the inability to perceive visual stimuli due to damage to the CNS, not damage to the optic nerve or eyes - Agnosia - some knowledge missing - Ability to recognize faces is important in discriminating familiar from non-familiar faces - Prosopagnosia - inability to recognize faces in the absence of other visual agnosia Prosopagnosia - Not due to difficulty with the eyes, but with the brain - Damage to visual association areas in the occipital lobe that are used to process/interpret visual information from the eyes - Individuals with prosopagnosia may not recognize others visually by their face, but they may recognize them by voice, smell, clothing, or other distinctive features - Individuals with prosopagnosia are able to recognize other objects, just not faces Fusiform Gyrus - Specialized area of the brain located in the right hemisphere that is responsible for recognizing faces - It is the location of damage in patients with prosopagnosia Comprehending facial expressions - Right hemisphere allows us to evaluate facial expressions - Those with right hemisphere deficits are less able to interpret facial expressions and identify emotions conveyed on the faces of speakers - Facial expression may be used to reinforce or alter the meaning of verbal utterances - Inability to process the emotions expressed by facial expressions restricts individuals to a less informed and more literal interpretation Prosodic deficits - There are two components to speech - Linguistic → aphasia - Language - Prosodic → RHD - Pitch, stress, timbre, cadence, tempo - Infuses words with emotions - Individuals with right hemisphere disorder may have difficulties processing (both comprehending and producing) prosodic components of speech - May be unable to identify emotions associated with an utterance, constraining these individuals to literal interpretations of verbal language - Misinterpretations of sarcasm and figurative language negatively impact communication - Difficulty using prosody to express emotion - Patients will experience emotion but will not be able to convey it through prosody - They will sound monotone - Individuals with right hemisphere deficits may seem monotone and emotionless, through they still possess the full range of emotions - May be experiencing higher levels of negative emotion due to right hemisphere disorder, though may not be able to convey those emotions with prosody of speech Inferencing deficits - Ability to take previous knowledge and experience and apply it effectively to the interpretation of small details - Allows for perceptions of macrostructure (gestalt impression) - Inability to read facial expressions may be due to inability to infer meaning of facial expressions - Not understanding nonliteral language - Inappropriate perception of humor and sarcasm may be due to inability to interpret nonliteral language and infer the true meaning of language Discourse deficits - The exchange of communicative information from speaker to listener - Most common discourse deficits in those with rights hemisphere deficits include - Lack of sensitivity to shared knowledge - A person would not give background information in a story when it is necessary for the other person to understand the message - Difficulties with turn taking - Constant interruptions - Not responding to questions - Difficulties with topic maintenance - Will jump from topic to topic with no segways in between Visuospatial deficits - Prosopagnosia - Simultagnosia - Inability to visually perceive multiple details at one time, often due to a lesion at the parietal-occipital area  - Individuals may perseverate on details of an object but cannot perceive the object as a whole - May be able to make an accurate guess of what the object is by visually assessing the object’s distinctive features or accessing the object using another sense - Cerebral achromatopsia - Rare loss of color vision due to trauma or damage to the cortex - Also known as color agnosia - Individual only sees the world in shades of gray Attentional deficits - Neglect - Inability to attend to sensory stimuli from - One side of their body (body neglect) - Environment (hemispatial neglect) - Side unattended to or unrecognized is the side of the body/environment that is contralateral to lesioned hemisphere - Most commonly neglected side of the body/space is the left side due to the right hemisphere lesion - Body neglect - Official name is somatophrenia when the individual is unable to perceive their own body parts as being - they see the limb but does not recognize it as a part of their body - Neglected body parts often display hemiparesis (weakness) - Motor function may remain intact for neglected limbs though the limbs may remain unutilized - Motor neglect is diminished use of a neglected limb despite being motorically intact - Hemispatial neglect - Mild cases of hemispatial neglect may be known as extinction - Individuals may be able to attend to the neglected side with prompting - In severe cases of neglect, individuals may be unable to recognize the existence of the neglected world via vision, auditory, and olfactory information - Involves multiple sensory modalities - Selective and sustained attention deficits - Necessary for attending, processing, and understanding language, important social cues, and social interactions - Deficits in selective and sustained attention may cause individuals with right hemisphere lesions to miss relevant information, be distracted by irrelevant stimuli, and further lose track of what is being spoken of - Can not selectively focus on 1 stimulus and inhibit the surrounding stimuli Neuropsychiatric disorders - It is important to understand and recognize disorders which may present alongside and interact with deficits and disorders that more highly concern SLPs - Anosognosia - Depression - Capgras delusion  - Fregoli delusion - Visual hallucinations - Paranoid hallucinations DEMENTIA Components of memory - Storage for short time period - Short term memory - Working memory - Storage for a long time period - Declarative memory - Semantic memory - Lexical memory - Episodic memory - Procedural memory Dementia - Acquired global loss of brain function with slow insidious onset - It is progressive with beginning symptoms not very noticeable - Only one type of dementia does not have a slow onset - Caused by a variety of diseases - It is a syndrome, not a disease itself - DSM IV defines dementia as memory loss plus one additional deficit in an area that affects activities of daily living (ADLs) - verbal/written expressive and receptive language - recognition/identification of objects - Inability to execute motor activities - Abstract thinking, judgement, and executive of complex tasks (executive functions) Mild cognitive impairment - not a dementia because it is not severe enough - Changes that are significant enough to not be within normal spectrum of changes with age, but not severe enough to affect ADLs - Symptoms include - Decreased ability to concentrate - Decreased word finding abilities - Decreased short term memory - Difficulty following detail heavy conversations/writings Allzheimer’s disease - Cortical dementia (cerebral cortex neuron death) that is the most common cause/etiology of dementia - Progressive and fatal disease with no known treatments to stop or slow progression - Onset usually after age 65 - Neuropathy includes presence of - Neurofibrillary tangles - TAU from microtubules separates and combines to form tangles destroying the microtubule - Amyloid plaques  - fatty substances develop outside of neuron resulting in communication breakdown between neurons and eventually neuron death - Granulovacuolar degeneration results from these plaques - General neural atrophy - shrinkage of cortex and widening of ventricles - Results from neuron death - Will have more fluid in skull space - Atrophy in areas of language and the hippocampus Stages of Alzheimer’s - Early stage - Motor function retained - Short term memory loss, word finding difficulties, comprehension of verbal language deficits, and personality changes - Will have deficits in receptive and expressive language - Early stage lasts 2 years on average - Mid stage - Negative impact on ADLs and reliance on others - More severe memory loss, attention deficits, dramatic personality changes, visuospatial and visuoconstructive deficits, and expressive language deficits - All dementia patient’s personality will change for the worse - they will become meaner - May experience wanderlust, sundowner syndrome, disorientation, and confusion - Mid stage lasts from 4 to 10 years - Severity of early symptoms increase and new symptoms arise - Late stage - Loss of motor function - loses procedural memory - May become non ambulatory, bedridden, incontinent, and unresponsive - Memory, cognition, and expressive language deficits are profound - May cause muteness and dysphagia Frontotemporal dementia - Degeneration of frontal and temporal lobes - Parietal and occipital lobe are typically spared - 3 related diseases, ⅔ have aphasia as earliest and most severe symptom - Pick’s disease - Progressive nonfluent aphasia - Semantic dementia - Will have both receptive and expressive language deficits, executive functioning deficits, and motor deficits Pick’s disease - Dementia resulting from progressive degeneration of frontal and temporal lobes - Insidious onset and progressive time course - Characterized by personality changes, antisocial and inappropriate behavior, and memory loss in absence of language deficits (no language deficits) - Neuropathy includes - Pick bodies - proteins in neurons that should not be there - Ballooned neurons - what results for the pick bodies in the neurons, destroys cell - Differentiated from Alzheimer’s disease early by: - Notable behavior, emotional, and personality changes (occur earlier) that occur as a result of frontal lobe degeneration  - These early changes in the absence of significant language deficits are also used to differentiate Pick’s disease from progressive nonfluent aphasia and semantic dementia, which present primarily as changes in modalities of language Semantic dementia - Typical progression of brain atrophy in semantic dementia - Mostly occurs in left hemisphere in the anterior temporal pole - Anterior temporal pole is important for semantic memory/conceptual knowledge of the world Progressive nonfluent aphasia - Typical pattern of brain atrophy in progressive nonfluent aphasia - Damage is greater on the left than the right - Also has memory issues Huntington’s disease - Subcortical dementia - Progressive terminal illness characterized by distinctive involuntary erratic body movements - May cause changes in personality, cognition, language, and emotion - May be diagnosed with hyperkinetic apraxia - Neuropathology includes production of mutant Huntington protein that creates degeneration of basal ganglia and hippocampus Vascular dementia - Mixed dementia (can have symptoms from any of the dementias) caused by small ischemic strokes within the cortex, subcortex, or both - Acute onset of symptoms - Characterized by multiple cognitive deficits - Memory loss, aphasia, apraxia of speech, difficulties with executive functioning that occur more suddenly - Hyperactive reflexes and weakness (spasticity) are present - Acute onset follow by stepwise progressions of degeneration - Each stroke creates a “step” of symptoms making the dementia worse - Neuropathology includes presence of small or unnoticed ischemic strokes - Multi-infarct dementia is cause by many, usually small, infarts to various areas of the brain - Cortical multi-infarct dementia is the result of small recurrent ischemic strokes to cortex - Lacunar state is the result of multiple subcortical thrombotic ischemic strokes in the brainstem, basal ganglia, and other subcortical structures Lewy body disease - Results in neuropathological changes in the brain due to the presence of lewy bodies in the cell body of neurons - Subcategorized into parkinson’s disease and dementia with lewy bodies Dementia with ley bodies - Combination of overall decrease of volitional movements and difficulty initiating motor movement alongside cognitive deficits - Neuropathology is result of deterioration of cortex and subcortex due to lewy bodies