Dual Stream Model of Language Processing

• The dual stream model describes two primary pathways in language processing:
  • Ventral Stream: Involved in semantic processing (meaning of words).
  • Dorsal Stream: Involved in phonological processing (sound aspects of language).
• Question: Which stream has bilateral components (right and left hemispheres)?
  • Answer: Both streams have bilateral elements.

Semantic and Phonological Processing

• Semantic Lexical Processing: Refers to the perception of the meaning of spoken words.

  • Occurs via the ventral stream.

• Phonological Processing and Motor Speech Preparation: Concerned with analyzing sounds and planning speech.

  • Occurs via the dorsal stream.

Primary Progressive Aphasia (PPA)

• Typical Degeneration Patterns:
  • Associated with various forms of PPA:
  • Agrammatic PPA: Characterized by telegraphic speech.
  • Semantic PPA: Involves loss of meaning.
  • Logopenic PPA: Marked by word-finding difficulties and phonologic errors.
  • Graphic PPA: Associated with writing difficulties but less common.

Cerebral Arteries and Language

• Major Cerebral Arteries Supplying the Left Hemisphere:
  • Critical for language and speech are:
  • Left Middle Cerebral Artery (LMCA): Most significant in language functions.
  • Other arteries include:
    • Left Posterior Cerebral Artery (L PCA)
    • Left Anterior Cerebral Artery (LACA)
    • Right Middle Cerebral Artery (RMCA)

Aphasia Syndromes and Jargon

• Jargon: A hallmark feature of specific aphasia syndromes, particularly:
  • Wernicke's Aphasia: Characterized by fluent but nonsensical speech.
  • Transcortical Sensory Aphasia: Similar to Wernicke's but with preserved repetition.

Global Aphasia

• Language Impairments in Global Aphasia:
  • Severely Impaired:
  • Auditory and written comprehension
  • Verbal and written expression
  • Common features include:
  • Stereotyping as primary verbalization.

Broca's Aphasia

• Language Impairments in Broca's Aphasia:
  • Mildly to Moderately Impaired:
  • Auditory comprehension
  • Difficulty processing complex syntax
  • Notable features of expression include:
  • Agrammatism
  • Anomia
  • Phonemic paraphasias
  • Circumlocutions

Differentiation of Types of Aphasia

• Transcortical Sensory vs. Wernicke's Aphasia:

  • A primary differentiation is in repetition ability.
  • Wernicke's patients have poor repetition.
  • Transcortical Sensory patients can repeat well.

• Aphasia with Gradual Onset:

  • Primary Progressive Aphasia is characterized by a gradual, not sudden, onset.

Phonemic Paraphasia

• Definition of Phonemic Paraphasia:
  • A type of language error where incorrect sounds are used in place of the correct ones.
• Example: Saying "bake" instead of "cake."

Phonemic Perseveration

• Definition: The inappropriate repetition of sounds or words.
• Example: Repeating "cat" when trying to say "hat."
  • This shows a perseveration because the sound from the earlier word affects the current word.

Semantic Paraphasia

• Definition of Semantic Paraphasia:
  • A language error where a wrong but related word is used.
• Example: Saying "door" instead of "window."

Unique Language Behaviors

• Naming Familiar Objects:

  • Example: Correctly naming "cup," "shoe," and "belt," then saying "cup" when pointed to a "book."
  • Behavior described as semantic perseveration.

• Open Fridge and Cheerios Example:

  • Phrase: "white cold drink."
  • Described as circumlocution: trying to describe rather than name.

• Overly Fluent Spoken Language:

  • Referred to as logorrhea or jargon.

• Conduit Approach:

  • Type of language error where a speaker attempts to correct wording but ends up mixing correct with incorrect terms.
  • Observed in individuals with conduction aphasia due to difficulty retrieving words.

Assessment of Aphasia

• Western Aphasia Battery Revised (WABR):

  • Assessments include:
  • Participation in life situations
  • Language impairment in verbal expression, auditory comprehension, reading, and writing.

• Confounding Factors in Assessments:

  • An example would be evaluating auditory comprehension using a pointing response format; factors such as environmental noise or visual recognition can confound results.

• Task from WABR for Word Finding:

  • Example: Naming tasks that require spontaneous verbal responses, allowing identification of anomia if responses are absent or delayed.

Living with Aphasia (ALA) Assessment

• "Wall Question" Explanation:

  • The question aims to gather insight into a person’s language use and perception of their ability to communicate.

• Ways to Populate Circle:

  • Self-ratings from ALA 2 regarding speaking, understanding, and writing.

Questions on Communication Experience

• Example Questions:

  • Questions that elicit information about communication and language environments include inquiries about frequency of communication with others and contexts where they face difficulties.

• Impact of Aphasia on Participation:

  • Questions regarding how aphasia affects the individual's daily life activities, participation in work or social events, and emotional well-being.