The Neuropsychological Organisation of Language

Question 1

What is language?

Answer 1

The ability to encode ideas into signals.

Question 2

How do we know that language is primarily processed in the left hemisphere?

Answer 2

The Wada test. This is where one hemisphere at a time is anaesthetised (by injecting a drug into either the left or the right carotid artery)

- If the left hemisphere is anaesthetised, language is disrupted in most people
- If the right hemisphere is anaesthetised, language is largely intact in most people

Question 3

The left carotid artery supplies…

Answer 3

the left ACA and MCA

Question 4

The two main areas involved in language processing are…

Answer 4

Broca’s area and Wernicke’s area

Question 5

Wernicke’s area is specialised for…

Answer 5

Language comprehension (input)

Question 6

Broca’s area is specialised for…

Answer 6

Language production (output)

Question 7

To have Broca’s aphasia does the damage need to be directly to Broca’s area?

Answer 7

You can have Broca’s aphasia without damage directly to Broca’s area.
Broca’s aphasia is named after the neurologist who discovered the area that was damaged in relation to the symptoms.
We have better imaging now so we can be more accurate about where the damage is; not necessarily damage to that specific area —> can be damage deeper to the insula cortex.

Question 8

Where is Wernicke’s area?

Answer 8

Wernicke’s area lies in the superior temporal lobe, posterior to primary auditory cortex.

Question 9

Where is Broca’s area?

Answer 9

Broca’s area is in the frontal lobe, anterior to the region of primary motor cortex that controls the movements of facial expression and speech.

Question 10

Wernicke’s and Broca’s areas are joined by a bi-directional pathway (white matter tract) called the..

Answer 10

arcuate fasciculus.

Question 11

What is an aphasia?

Answer 11

Aphasia = Acquired language disorders

Question 12

Name the 6 types of aphasia.

Answer 12

1. Wernicke’s aphasia
2. Broca’s aphasia
3. Conduction aphasia
4. Transcortical sensory aphasia
5. Transcortical motor aphasia
6. Global aphasia

Question 13

Name the aphasia:
Fluent speech
Impaired comprehension
Impaired repetition
Impaired naming
No motor impairment

Answer 13

Wernicke’s aphasia

Question 14

What does Wernicke’s aphasia sound like?

Answer 14

They speak at a normal pace but the content doesn’t make sense

Question 15

To have Wernicke’s aphasia does the damage need to be directly to Wernicke’s area?

Answer 15

No, there are regions heading into the parietal lobe which can cause Wernicke’s.

Question 16

Do Wernicke’s patients have much insight into their condition?

Answer 16

Many Wernicke’s patients don’t seem to have much insight into what their disabilities are.

Question 17

Name the aphasia:
Non-fluent speech
Good comprehension
Impaired repetition
Impaired naming
May have right hemiplegia (more likely arm than leg)

Answer 17

Broca’s aphasia

Question 18

Do Broca’s patients have much insight into their condition?

Answer 18

Tend to be more aware of difficulties and can get frustrated.

Question 19

Conduction aphasia is a __________ syndrome.

Answer 19

Disconnection

Question 20

Name the aphasia:
Fluent speech
Good comprehension
Impaired repetition
Impaired naming

Answer 20

Conduction aphasia

Question 21

Name the aphasia:
Fluent speech
Poor comprehension
Good repetition
Impaired naming

Answer 21

Transcortical sensory aphasia

Question 22

Name the aphasia:
Non-fluent speech
Good comprehension
Good repetition
Poor naming

Answer 22

Transcortical motor aphasia

Question 23

Where would expect the lesion to be for transcortical sensory aphasia?

Answer 23

Posterior to Wernicke’s area

Question 24

Where would expect the lesion to be for transcortical motor aphasia?

Answer 24

Anterior or superior to Broca’s area

Question 25

Name the aphasia:
Non-fluent speech Impaired comprehension
Impaired repetition
Impaired naming
Right hemiplegia

Answer 25

Global Aphasia

Question 26

Name two disorders of language processing (reading and writing), that often parallel aphasia.

Answer 26

Alexia is the loss of the ability to read as a result of brain damage.
Agraphia is the loss of the ability to write as a result of brain damage.

Question 27

Patients with aphasia usually also have…

Answer 27

Agraphia, as normal writing requires intact functioning of the entire language apparatus. Thus, patients with alexia typically also have agraphia.

Question 28

Diagnosis?
The patient is able to see and understand language, but is unable to read.
Why can this patient see and understand language?

Answer 28

Alexia without Agraphia.
The patient is able to see because the visual area in the right hemisphere are intact.
The patient is able to understand language because the language areas in the left hemisphere are intact.

Question 29

Why is it that a patient with Alexia without Agraphia can’t read?

Answer 29

The patient is unable to read because the visual information from the intact right hemisphere visual cortex is disconnected from the language areas because there’s damage to the splenium of the corpus callosum.

Question 30

Which arteries irrigate the occipital lobe and splenium?

Answer 30

The left and right posterior cerebral arteries.