Neural basis of language Flashcards
Where is Broca’s area? Lobe and Hemisphere?
Left, prefrontal areas - part of inferior frontal gyrus
Who was Broca’s patient called and why?
Patient Tan: he could only say one word, “tan”
Where is Wernicke’s area?
left temporal lobe
Where did Ludwig Lichtheim (1880s) find lesions in his patients who had impairments repeating words?
lesion in the area that connects Broca’s and Wernicke’s area -articula fascius
Norman Geschwind (1960s) model said what about different brain areas?
The model described different areas playing different roles: Language network involving multiple areas
Comprehension extracted in Wernicke
Transferred to Broca’s
Broca translates it into speech
Importance of arcuate fasciculus for transfer of information from comprehension to production
Which hemisphere dominates for language in most right handed people?
Left
What is alexia?
Alexia is a term describing a partial or complete inability to read.
What is agraphia?
Agraphia is an impairment or loss of a previous ability to write.
The 3 types of fluent aphasia?
Fluent: speech production is fluent but there are problems in speech comprehension
Wernicke’s aphasia
Conduction aphasia
Transcortical sensory (isolation)
The 3 types of non-fluent aphasia?
Non-fluent: speech comprehension is spared, but speech production is non-fluent.
Broca’s aphasia
Global aphasia
Transcortical motor
Characteristics of Broca’s aphasia?
Difficulty in planning and organising spontaneous speech (effortful speech), motor planning of the articulation, associated with paralysis of the right upper limb and buccofacial apraxia, Telegraphic speech due to agrammatism, Patients show fewer difficulties when they are not required to spontaneously initiate speech (e.g., recognising correct vs incorrect sentences), Repetition might be less impaired than spontaneous speech, but still poor.
What is agrammatism?
difficulties in using syntax to determine the relationships between words (subject-object)
What is buccofacial apraxia?
difficulty in moving mouth and face
Characteristics of Wernicke’s Aphasia (fluent)?
Difficulty in auditory comprehension
Difficulty in repeating back
Patients hear sounds but are not able to attach meaning to them
Production of language is spared (fluent aphasia), however speech does not make sense -> Semantic impairment
Use of neologisms (newly coined words or expressions) – jargon aphasia
Patients can be oblivious to their errors
What is a neologism?
neologisms (newly coined words or expressions)
What is the arcuate fasciculus and which aphasia where there’s a lesion here?
arcuate fasciculus = white matter pathways that connect Broca’s and Wernicke’s areas Conduction Aphasia (fluent)
Characteristics of conduction aphasia (fluent)?
Problem with repetition
Some problems with production
Unlike some of Wernicke’s aphasic patients, they can monitor their speech (aware of their errors)
Conduit d’approche: after a few attempts, patients produce the right word -> reveals preserved knowledge of how the word should sound
Good comprehension
The 2 types of Transcortical aphasias?
Transcortical Sensory Aphasia (TCSA) (fluent)
Transcortical Motor Aphasia (TCMA) (non-fluent)
What are both types of transcortical aphasia characterised by?
intact repetition
3 characteristics of Transcortical Sensory Aphasia (TCSA) (fluent)?
Disorder of comprehension
Production is filled with neologisms
Lesions near junction of temporal, parietal and occipital lobes