Right Hemisphere Dysfunction (right CVA) Flashcards
Hemispheric Asymmetry
the right and left hemispheres of the brain are anatomically and functionally asymmetrical
differences are greatest in certain areas surrounding the sylvian fissure
- sylvian fissure is slightly longer in the left hemisphere than on the right
- planum temporale is a part of the superior surface of the superior temporal gyrus; this area is larger on the left than the right for most people
- left temporal opercular region is larger and more infolded on the left than on the right; region is aka Broca’s area
Hemisphere Connections
the two hemispheres are well connected via the corpus callosum
contains more than 300 million axons aka commissural fibers
Right Brain
uses feeling “big picture” oriented imagination rules symbols and images present and future philosophy and religion can “get it” (meaning) believes/appreciates spatial perception knows objects function fantasy based present possibilities impetuous and risk takers
Left Brain
uses logic detail oriented facts rule words and language present and past math and science can comprehend knowing/acknowledges order/pattern perception knows object name reality based forms strategies practical and safe
Left Hemisphere
Language: Speaking Aloud; Auditory Comprehension; Naming; Reading Comprehension; Reading Aloud; Writing
Constructions: Internal Detail
Calculation: Arithmetic Processing
Memory: Verbal
Miscellaneous: Praxis
Right Hemisphere
Language: Auditory Comprehension; Reading Comprehension; Prosodic Expression
Prosodic Comprehension
Constructions: External Configurations
Calculations: Spatial Arrangement
Memory: Visuospatial
Miscellaneous: Facial Recognition
Right Hemisphere Functions
The right brain is seemingly responsible for:
- arousal, orientation and attention
- visual perception
- emotional experience and expressions
Arousal
(right hemisphere is dominant for)
general readiness to respond to external stimuli; alert; ready to react
Orientation
(right hemisphere is dominant for)
directing one’s attention to a specific stimulus, event, or location; know where you’re going
Vigilance
(right hemisphere is dominant for)
sustained attention used to detect changes in the stimulus
Selective Attention
(right hemisphere is dominant for)
ignoring some stimuli while paying attention to certain specific stimuli
Sustained Attention
(right hemisphere is dominant for)
prolonged periods of attention to a task; focused attention
Right Hemisphere appears to process: (visual perception)
holistic, gestalt-like stimuli
geometric and spatial information
facial recognition
body image
Right Hemisphere is dominant for:
arousal
orientation
vigilance
selective attention
sustained attention
Holistic; Gestalt-like Stimuli
looking at big picture; grasping meaning of total picture
Geometric Spatial Information
understanding or recognizing spatially organized shapes or figures
Facial Recognition
responsible for recognizing familiar faces; 4-10 month old infants will show interest in their mother’s faces (high amplitude sucking)
Body Image
helps maintain proper body image and what’s acceptable socially based on life experience, etc.
Right Hemisphere is dominant for: (emotional experiences/expression)
emotions
perceptions of temporal order
perception of musical harmony
certain aspects of communication
Emotions
the expression of being angry, happy, sad, etc. (all the different emotions); understanding how the emotions impact you based on the stimuli you’re receiving from the environment (amygdala—fight and flight responses, etc); where that info is stored—what it means to be happy, sad, etc.
Perceptions of Temporal Order
dominant for perceiving the temporal order or sequence of events; understanding of serial-ness of events
Perception of Musical Harmony
music and processing of acoustic signals; generic music; understanding harmonies, etc.
Certain Aspects of Communication
slide with blue chart
Communication Functions of the Right Hemisphere
- possible interplay b/w the right and left hemispheres with regards to discourse comprehension and production
- right hemisphere may be less efficient in understanding verbs than nouns
- right hemisphere may help make inferences implied in verbal exchanges
- communicative efficiency and specificity may be centered in the right hemisphere
- understanding alternative and ambiguous meanings
- understanding or expressing emotional tone of verbal expression
Communicative Functions of the Right Hemisphere Cont…
- understanding or expressing prosodic aspects of speech
- understanding contextual information of verbal expression
-managing pragmatic communication skills: turn-taking topic maintenance social appropriateness of communication eye contact
Etiologies (NEuropatholgies)
CVA, tumors, head trauma and various neurological disease processes
Individuals who sustain RHD secondary to posterior lesions do not have motor disabilities; those with frontal lobe damages will have motor disturbances
Grouped Symptoms Pts w/RHD might exhibit
perceptual and attention deficits
affective deficits
communication deficits
Perceptual and Attention Deficits
left-neglect
visuospatial impairments
forms of disorientation
Left Neglect
Reduced sensitivity to stimuli, reduced awareness of space or absence of previously learned responses from stimuli in certain visual fields:
- neglect can result from damage to any lobe
- neglect can be right or left dominant
- right parietal lobe damage produces left-neglect in most pts
Left Neglect Characteristics
Right focus: stimuli on right side of patient seems to capture and hold attention of patient; left neglect and right focus
Difficulty shifting attention from right-to-left
Failure to perceive left-sided tactile or perceptual stimuli: touch: pinprick, etc on left side; don’t perceive it; may or may not perceive pain on left side, but not something we’d do
Failure to copy the left side of a picture or a geometric design: clock draw
Disownership of left body parts or belongings
Denying illness (anosagnosia)
Left-neglect in reading/writing: starts in the middle and only read right half
Prosopagnosia (Facial Recognition Deficits)
Prosopagnosia:
- seen in Pts with posterior right hemisphere damage
- difficulty recognizing familiar faces
- difficulty choosing pictures of faces just shown
- problems naming the pictures of faces of famous persons
Constructional Impairments
- problems constructing block designs
- difficulty reproducing two-dimensional stick figures
- errors in drawing or copying geometric designs
Often seen in Pts with all kinds of brain damage
- with left hemisphere involvement: Pt will draw w/difficulty but make fewer mistakes; drawings are better w/models than without
- with right hemisphere involvement: Pt will draw hastily, make many mistakes, add unnecessary lines to correct mistakes, do not show improvements w/models
Attentions Deficits
reduced state of arousal: Pt’s w/RHD are described as hypoaroused
difficulty in sustaining attention: Pt’s attention wanders from task to task or from stimuli to stimuli
difficulty paying selective attention: Pt may find it difficult to focus on a particular stimuli in the presence of multiple stimuli
Topographic Disorientation
- the inability to orient in the surrounding as a result of focal brain damage
- may result from the inability to make use of selective spatial information (e.g., environmental landmarks) or to orient by means of specific cognitive strategies such as the ability to form a mental representation of the environment, also known as a cognitive map
- It may be part of a syndrome known as visuospatial dysgnosia.
Geographic Disorientation
??
Reduplication Paramnesia
is the delusional belief that a place or location has been duplicated, existing in two or more places simultaneously, or that it has been ‘relocated’ to another site
although rare, is most commonly associated with acquired brain injury, particularly simultaneous damage to the right cerebral hemisphere and to both frontal lobes.
Visual-Perceptual Deficits
- difficulty recognizing line-drawn pictures or incomplete drawings
- drawings that distort the representation by showing unusual size, dimension or orientation
- drawings that are superimposed on other drawings
Affective Deficits
Pts with RHD tend to be emotionally indifferent:
- difficulty understanding emotions
- difficulty stating the emotions depicted in pictures
- problem recognizing emotions expressed in isolated spoken sentences
- difficulty understanding emotional tone of voice
- difficulty expressing their own emotions correctly
Memory Deficits
Nonverbal Amnesia:
- references impaired recall of nonverbal visual material
- ex: impairment in the retention of complex visual patterns and faces
Neuropsychiatric Disorders: Visual Hallucinations
- claims to see something that the observer cannot see
- may occur as part of a seizure or may be associated w/visual field deficits
- most common form of hallucination in persons w/dementia
Neuropsychiatric Disorders: Mania
-elated and/or irritable mood lasting at least one week and combined with any of the following: hyperactivity flight of ideas grandiosity diminished sleep distractibility lack of judgment rapid speech
Communication Deficits are different than those associated with left-hemisphere damage:
Communication problems are found in about 50% of individuals who have RHD
RHD: no word-retrieval issues
RHD: no significant circumlocutions or paraphasias
RHD: speak in grammatically accurate sentences
RHD: have good comprehension
pts w/RHD do exhibit: prosodic deficits; impaired discourse; semantic problems; pragmatic deficits
Prosodic Deficits
prosody references: stress patterns, intonation, rhythm, melodious qualities of speech that convey meaning
output may be:
monotone
impaired in stress patterns; may change intensity levels
reduced rate of speech
devoid of emotion
impaired in prosodic comprehension; difficulty understanding the emotional tone heard
Impaired Discourse
Discourse is a set of social communication skills; may involve narration, procedures, expository discourse
Pts with RHD exhibit:
- difficulty distinguishing significant from irrelevant information
- difficulty understanding implied meanings, abstract words, metaphors, irony and humor
- premature and incorrect inferences
- confabulation and excessive speech
Semantics
left hemisphere: active in promptly and quickly understanding concrete meanings of words
right hemisphere: involved in understanding or producing words w/complex, abstract, metaphoric, and multiple meanings
Semantic Difficulties
pts w/RHD exhibit:
- difficulty understanding implied, alternative or abstract meanings
- failure to grasp the overall meaning of situations, events, stories or pictures (miss the central message)
- difficulty understanding idioms, proverbs and metaphors
- difficulty naming abstract categories in contrast to the names of individual items in a category
- difficulty w/irony, humor, and sarcasm
- problems in understanding logical errors in sentences
Pragmatic Difficulties
Pragmatic language problems could include:
- difficulty in conversational turn-taking
- difficulty with topic maintenance
- difficulty in maintaining eye contact
- insensitivity to communicative contexts: assume too much about what their listeners know about the topic of conversation
Associated Language Difficulties
Right hemisphere’s receptive language capabilities:
-disturbance in comprehension of logical syllogisms (ex. all trees have root systems; all root systems need nitrogen; therefore, all trees need nitrogen)
-pictorial interpretations of metaphors (ex.it’s raining cats and dogs)
-concrete interpretation of proverbs/idioms; abstract verbal tasks pose problems
(ex. the greatest talkers are the least doers;
a heavy heart)
