COSI 357: Right Hemisphere Syndrome

Compare right hemisphere stroke to left hemisphere stroke.

• incidence numbers between left and right hemisphere strokes are similar

• but RHS deficits are often neglected and undiagnosed

  • deficits are much more subtle

  • “just not the same”

  • relatively little attention in basic and clinical research

• just like left hemisphere deficits, right hemisphere deficits can significantly impact everyday life

What impairments are associated with right hemisphere strokes?

• attention deficits

• neglect

• visuoperceptual deficits

• cognitive communication deficits

• affective and emotional deficits

what is a cognitive communication disorder?

• Cognitive-communication disorders are communication impairments resulting from underlying cognitive deficits due to neurological impairment.

• These are difficulties in communicative competence (listening, speaking, reading, writing, conversation and social interaction) that
  result from underlying cognitive impairments (attention, memory, organization, information processing, problem solving, and executive functions).

• These disorders are distinct from other neurological communication disorders (e.g., aphasia, dysarthria etc.) and require specific techniques

What is attention?

• Attention

  • Fundamental to cognitive processing

  • Responsive but not overwhelmed

  • Aware but not distracted

• Basic assumptions:

  • Limited capacity to represent events

  • Attention protects this limited capacity

  • Attention is a limited resource

  • Different types of processing required different levels of attention

  • Attention may be unitary/not unitary

What is arousal?

• Arousal

  • The neural and behavioral readiness to respond

  • Fundamental to all other attentional operations

What is orienting?

• Orienting
   Directing attention toward a stimulus or location

what is vigilance?

a state of alertness necessary to processing intermittent stimuli; pre-stimulus mode of attention

what is maintenance?

sustaining attention over time; can occur without vigilance

what is selective attention?

capacity to selectively attend to some, but not other, stimuli

what are the 5 types of attention?

• arousal

• orienting

• vigilance

• maintenance

• selective

What types of arousal and orienting deficits can occur with right hemisphere syndrome?

• Arousal and orienting
  • “hypoaroused”
  • Reduced and restricted interaction with the
  environment
  • Need more intense stimuli and more time to prepare to attend

What types of vigilance and sustained attention deficits can occur with right hemisphere syndrome?

• Vigilance and sustained attention
  • May not be able to sustain attention over a period of
  time
  • Failure to process crucial information

what type of selective attention deficits can occur in right hemisphere syndrome?

requires adequate arousal, orienting, and vigilance

What is neglect?

• Neglect - a “hallmark” sign
• Related to attentional impairments
• Pt. fails to report, respond, or orient to stimuli on the
contralateral side
• More long lasting and severe than in LHD
• Most often occurs in lesions on the frontal, temporal,
or parietal cortex
• Can occur with subcortical lesions
• Most commonly seen in the visual modality

-denial or neglect is common due to the reduced awareness of the the deficit

-may disrupt motor sequence (eye movement)

-may be related to difficulty in shifting and disengaging attention

What is somatoparaphrenia?

body neglect

• Somatophrenia is when the individual is
  unable to perceive their own body parts as
  being part of themselves

  • Neglected body parts often display hemiparesis

• 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

what is hemispatial neglect?

• Mild cases of hemispatial neglect may be known as extinction
• Individuals may be able to attend to 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

what are commonly observed left neglect behaviors in RHD patients with moderate to severe neglect?

• responding to people and objects to the left of their body midline

• attending to the left while conducting self care activities (grooming, bathing, eating, dressing)

• moving, attending to, and recognizing left limbs

• navigating through halls and doorways without bumping into left sided walls

• reading the left half of printed materials

• appropriate use of margins and spacing when writing

• following presentations in films, videos or on TV

• localizing sounds emanating from the left

• insight into and awareness of deficits including hemiplegia and neglect

• actively participating in the rehabilitation process

what are visuoperceptual deficits?

• Visuoperceptual deficits
  • Visual attention
  • Visual integration
  • Visual memory
  • Spatial orientation
  • Topographical orientation

what are cognitive communication deficits of RHD?

• Cognitive-communication deficits
• Reduced discourse comprehension and production
• Reduced communicative efficiency and specificity
• Reduced capacity to process alternative and ambiguous
meanings
• Reduced sensitivity to contextual information
• Reduced sensitivity to emotional tone
• Reduced use of prosodic information
• Reduced appreciation of shared knowledge (social cognition
• Reduced reflection (shallow responses)

what is the heart of communication deficits in RHD?

• Discourse

  • Heart of communication deficits in RHD

  • Procedural, expository, narrative, conversational

  • Involves a speaker, listener, and a situational context

  • To be successful:

    • Awareness of the general topic

    • Purpose of the exchange

    • Limits of shared knowledge

    • Cultural rules

    • Means of repairing a communicative breakdown

what are the comprehension aspects of discourse deficits?

• Comprehension

  • Gist of written and spoken narrative

  • intended and implied meanings

  • New information and revision of old information

  • Emotional content

  • Paralinguistic info

  • Shared knowledge

  • Conversational rules and
    conventions

  • Setting, purpose and role
    of communication

what are the production aspects of discourse deficits in RHD?

• Production

  • Impaired ability to generate a macrostructure

  • Reduced level of information content

  • Reduced specificity

  • Reduced flexibility

  • Reduced ability to generate alternative
    meanings

  • Reduced use of conversational conventions

  • Excessive speech output

  • Unelaborated speech output

what are the comprehension aspects of prosodic deficits in RHD?

Comprehension

• Emotional

  • Discriminate mood in neutral context or without support

  • Incongruent message/prosody

• Linguistic

  • Parts of speech based on stress

  • Auditory discrimination

  • Appropriate stress in sentences

  • Determining sentence type from prosodic information

what are the production aspects of prosodic deficits in RHD?

Production

• Emotional

  • Flat, robotic, monotone

  • Matching prosody to emotion

  • Use of pitch variability to

  • Increased reliance on semantic information rather than prosody

  • Linguistic

  • Minimal use of emphatic stress

  • Reduced ability to alter fundamental frequency to delineate sentence type

what are some affective and emotional deficits found in RHD?

• Affective and emotional deficits
  • Reduced use of facial expression to convey emotion
  • Reduced sensitivity to facial expressions of others
  • Reduced use of prosody to convey emotion
  • Reduced comprehension of emotional prosody
  • Can have delirium, agitation, psychosis (rare)

what is simultagnosia?

• Inability to visually perceive multiple details at one time often due to lesion at parietal-occiptal area
• Individuals may perseverate on details of an object
but cannot perceive 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 (e.g. feeling the object, smelling the
object, etc..)

what is 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

what neuropsychiatric disorders are commonly associated with RHD?

• 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

what is anosognosia?

An individual’s inability to recognize/realize they
have deficits.
• Anosognosia: To not know that you don’t know
• These patients usually are calm and assured that if
there is a problem it does not have anything to do
with them
• May blame performance or problems on SLP,
caregivers, or explain away failures by refusing to
acknowledge possibility of deficits

Discuss depression and neurogenic disorders.

• Common in any population following disease,
surgery, stroke, or trauma
• May go unnoticed or masked by other deficits in
those with right hemisphere disorders
• Expression may not be indicative of emotional state
• If depression is suspected, SLP must refer to
appropriate mental health authorities

what is capgras delusion?

• Belief that loved ones, significant others, or family members have been replaced by imposters who look and sound like the original person
• May present in those with epilepsy, TBI, stroke, or acute lesion to right hemisphere
• Current explanation involves the disconnection of the area of brain responsible for processing faces and the area of the brain responsible for producing the normal
emotional response in reaction to seeing the face

what is the fregoli delusion?

• The delusional belief that a familiar person is able to take on the guise of another person, at times many other people, and assumes their exact appearance
• Often accompanied by a degree of paranoia

what are visual hallucinations?

• When an individual is perceiving something visually that does not exist
• Due to lesions or seizure activity usually in posterior right hemisphere among visual processing areas
• Nature of hallucinations vary widely and unpredictably between individuals

what are paranoid hallucinations?

• Visual and/or auditory
• Perceived as threatening, ominous, or
foreboding