1. Right Hemisphere Disorders (RHD)

2. In 1974, William O. Douglas, Associate Supreme Court Justice suffered a stroke  He recovered quickly, checked himself out of rehab.  In court he dozed and asked irrelevant questions and rambled on. He was asked to resign------ “he came back to his office, buzzed for his clerks and asked to participate in, draft, and even publish his own opinions separately; and he requested that a tenth seat be placed at the Justices’ bench.” (Gardner, 1982)

3. Ok, the history  Historically, non-dominant hemisphere strokes were not referred to slp clinics  Mainly because the primary disorders are related to nonverbal cognitive systems  Don’t display word-finding and grammatical deficits associated with aphasia

4. Zoom to today, (history lesson is done!!)  Non dominant strokes now referred usually for:  Pt has a swallowing problem or motor speech deficit  Pt has an old RHD recently suffered a left hemisphere stroke  Pt has communicative difficulties caused by right hemisphere stroke---as with Justice Douglas

5. Language Evaluations  We might typically begin with an aphasia assessment tool, but:  RHD pts are most often not aphasic in that they can normally process most words and sentence in isolation

6. Language Comprehension  Sometimes perform as poorly as aphasic subjects  Can display good word comprehension, with mild deficit when presented with up to 4 semantically similar picture options  Not usually deficient short term memory span  Can follow directions (Token Test)

7.  Difficulty arranging words into a grammatical sentence  Problems with sentence comprehension with thematic roles in passive sentences  Subtle!

8. RHD: Language Production  Tend to name common objects effectively  Word finding problems occur on divergent thinking (expansion) tasks  Tend to generate fewer words (fluency)  More problems with lexical semantics than with phonology and syntax  Errors increase with processes that are “less automatic”

9. RHD: language production  May score similarly on clinical tests but for different reasons!  Because RHD pts have impaired attention, perception and organizational skills  So let’s look at the primary cognitive impairments caused by right hemispheric stroke

10. RHD: awareness of deficits  Anosognosia: lack of awareness or recognition of disease or disability  “lack of insight” or “imperception of disease”  Essentially, pts are unable to become aware of the neurological dysfunction  But, denial of impairment is a psychological defense mechanism---a pt who is strictly in denial is considered to be capable of awareness of deficit

11.  Anosognosia is usually observed as lack of awareness of paralysis  Self awareness of deficits was not correlated with actual task performance (Pendley and Ramsberger, 19960

12. Visuospatial Functions  WAIS scores show a pattern that is reversed relative to aphasia  RHD pts are likely to have a discrepancy score in which the Performance IQ (requires visuospatial recognition and reasoning skills) is lowered relative to the Verbal IQ

13.  Left neglect is more common that right neglect--- pts with posterior RHD bump into things on their left, leave food on the left side of a plate, dress only the right side, draw on the right side of an object  Wheel chair accidents!  Crossing Out Test, Line cancellation Test, etc.

14. Auditory-Vocal Modalities  Auditory agnosia: impaired ability to recognize sounds despite adequate hearing  May refer to deficient recognition of nonverbal or environmental sounds (auditory sound agnosia)

15. Emotion  Complex relationship between the limbic and the autonomic nervous systems---a message recognized in the cognitive cortex  Although both hemispheres are involved, the RH is dominant for emotion  RHD pts may display flat affect or indifference that accompanies left neglect  Hypoarousal to emotional pictures

16. Attention and Reading  RHD: tend to misread the beginning of words,  Some omit or misread words on the left side of the page  Some have both of these problems  Misreading the left side of words or left side of a page indicates neglect dyslexia

17. Emotion and Prosody  Aprosodia:  Flat contour or monotone  Failure to identify emotional tone in mundane sentences  Unable to detect happy, sad or angry faces

18. Interpreting Situations  RHD: difficulty recognizing emotion or humor in pictured scenes; unlike aphasics!  RHD: difficulties with sorting implicit themes like “love” from explicit themes like getting a hug  Suggests that RHDs have a problem with inferring the nature of situations when it is not concrete or obvious

19. Metaphor comprehension  “Metaphor is a pragmatic convention used for studying comprehensions of speaker-meaning that differs from literal content” (Marquart, 2000)  Inference is presumed to be a necessity  Interpreting idioms like “bury the hatchet” or “shoot the bull”

20. Discourse  RHDs recall main ideas better than details and explicit information  Tend to “miss the point”