Introduction
- (Wash your hands), introduce yourself, and ask for permission (consent) to examine.
- Assessment of speech can be a tricky examination. The key is to be systematic yet quick, and to assess as many 'types' or 'qualities' of the speech as rapidly as possible in order to get a rough idea of what kind of pathology you are dealing with.
- Remember that you are testing several features: the quality of the speech (dysarthria, dysphonia), the content of the speech (expression - Broca's area), and the patient's understanding of your commands (receptive function - Wernicke's area).
Types of Dysphasias
Broca (expressive):
- Difficulty in expression of speech. Caused by a lesion in at the inferior frontal gyrus (on language dominant hemisphere).
- Speech is slow and 'forced', and features short phrases. Comprehension is usually intact. Repetition of both auditory and visual stimuli is usually impaired.
Wernicke's (receptive):
- Difficulty in comprehension. Caused by a lesion in at the posterior part of superior temporal gyrus (on language dominant hemisphere).
- Speech may appear quite fluent, although may not necessarily make sense. Repetition of both auditory and visual stimuli is usually impaired.
Conduction aphasia:
-Difficulty in repetition. Caused by a lesion in the arcuate fasciculus (inferior parietal lobe of language dominant hemisphere - connects Wernicke's to Broca's areas).
Transcortical aphasias:
- Arcuate fasciculus intact, so repetition spared. 3 types:
- Mixed: Both Broca's and Wernicke's areas are damaged, leaving little comprehension/expression of language, however repetition is possible.
- Sensory: Like Wernicke's, but with a lesion either posterior or superior to Wernicke's area, leaving repetition spared.
- Motor: Like Broca's, but with a lesion either anterior or superior to Broca's area, leaving repetition spared.
- NB: Global aphasia is loss of all three - Broca's, the arcuate fasciculus and Wernicke's areas, resulting in a total language disturbance.