10. Language and cognition

Question 1

What is cognition?

Answer 1

The acquisition, retention and use of information that allow successful behaviour on our complex and changing environment
Encompasses concepts such as:
-Attention
-Perception (not sensation)
-Memory and learning
-Emotion and social cognition
-Symbolic representations (language etc)
-Reasoning and problem solving

Question 2

Describe the areas of the cortex that are involve in cognition within a sensory modality?

How does this allow the appreciation of music, detection of danger, integration of other peoples behaviour?

Answer 2

Primary areas: Receive unprocessed modality data

Association areas + sub-cortical components: Determine the perceptual qualities of the modality

Allows the appreciation of music, detection of danger, integration of other peoples behaviour….
Modal qualities from the higher cortex (e.g. For hearing pitch, volume, timbre, harmonics) are integrated with themselves and information from other sensory modalities (e.g. sound and vision)

Question 3

How are multiple sensation integrated in order to come to a conclusion of a situation?

Answer 3

The 3 sensory modalities (Vision, auditory and somatosensory) arrive in the cortex mantel at 3 primary locations.

The sub-cortical structures and association fibres move the information through the associated cortices for processing and integration to become either a reflex or cognitive state

Question 4

What events must occur prior to the motor output in multi-sensory integration?

Answer 4

1. Sensory information about the environs and body project to the primary cortical areas (visual, somatosensory, auditory)
2. Processed and unprocessed information is then passed to the sensory association areas in the parietal lobe and the temporal lobe for integration.
3. From there integrated information is shared with the supplementary motor cortex (which is processing information about intent in association with other frontal lobe areas) & thence to the pre- & motor cortex to allow incorporation of sensory input into planned integrated motor events

Question 5

What is synaesthesia?

Answer 5

The conflation of sensory experiences from one sensory domain with another sensory experience from a different sensory domain. (or the mixing of two modalities of the same sensory domain)
E.g. Colour-graphemic synaestesia where specifc black and white shapes are perceived in colour.

Question 6

Which areas of the brain are stimulated when speaking words?

Answer 6

Primary motor cortex

Broca’s areas (sentence construction and syntax)

Question 7

Which areas of the brain are stimulated when hearing words?

Answer 7

Auditory cortex

Wernicke’s areas: Word comprehension

Question 8

Which hemisphere is speech dominent?

Answer 8

Left

in Wada Test

Question 9

What is aphasia?

Answer 9

the partial or complete loss of language abilities following brain damage

Question 10

Which areas of the brain are stimulated when “you say written words”?

Answer 10

Seeing: Primary visual cortex

Speaking: Motor cortex and Bronca’s area

Hearing: Auditory cortex and wernicke’s area

Complex language integration: Angular gyrus

Question 11

Location and function of the angular gyrus?

Answer 11

The angular gyrus is a region of the brain in the PARIETAL lobe, that lies near the superior edge of the temporal lobe, and immediately posterior to the supramarginal gyrus

Function: Processes related to language, number processing and spatial cognition, memory retrieval, attention, and theory of mind

Question 12

Describe the Wernicke-Geschwind model in reading aloud?

Why does conduction occur?

Answer 12

• Visual information is passed to Wernicke’s area via the angular gyrus, and so on to Broca’s area etc.
• The visual cortex can pass information directly to Broca’s area but the path remains elusive

•A form of aphasia (conduction) occurs when the link between the two areas (the arcuate faciculus) is damaged, and is typified by a reduced ability to repeat spoken words.

Question 13

What is the neurological bases for hearing, understanding and repeating spoken words?

Answer 13

1. Afferent information arrives at the auditory cortex and Wernicke’s area (left temporal lobe).
2. Wernicke’s area comprehends the words and passes the information to Broca’s area for sentence construction and syntax.
3. Broca’s area stimulates the motor cortex to control the lips & tongue etc.
   The spoken word is repeated.

Question 14

Action of Wernicke’s area?

Answer 14

Comprehends the words and passes the information to Broca’s area

Question 15

Action of Broca’s area?

Answer 15

Has the motor programs for generation of language and sentence construction.

Stimulates the motor cortex to control the lips and tongue etc

Question 16

What is Wernicke’s aphasia?

Answer 16

Speech flows but is often gibberish because the patient has reduced comprehension of speech (there own or others) consequently sentence construction is very poor.

Associated symptom: Hearing/understanding malfunction. Sufferers do not understand their OWN speech. Hence are unconcerned they do not make sense.
ALSO inability to undersand written words.

Remember: Wernicke’s area is responsible for word COMPREHENSION

Question 17

What is Broco’s aphasia?

aka Motor or non-fluent aphasia

Answer 17

Patients have difficulty speaking e.g. stuttering.
Unlike Wernicke’s aphase:
- They are aware they aren’t making sense
-Are able to respond to spoken or written word.

Question 18

Link between Broca’s and wernickes area?

Answer 18

Arcuate faciculus

Question 19

What is syntax?

Answer 19

the arrangements of words and phases to make a well constructed sentence

Question 20

Comparison between Broca's and Wernicke's aphasia:
Speech characteristics?
Grammar
Syntax?
Word structure?
Repetition?
Compehension?

Answer 20

Broca's:
Speech characteristics: Jumbled with breaks/halts
Grammar: Poor
Syntax: Poor
Word structure: Jumbled
Repetition: Yes
Compehension: Maintained

Wernicke's:
Speech characteristics: Fluent but non-sensical
Grammar: Good
Syntax: Good
Word structure: Wrong/ inverted
Repetition: No
Compehension: Lost

Question 21

Aprosodias?

Answer 21

When a person is unable to interpret or convey language with an emotional content (such as pitch, rhythm)

Question 22

Note that the right side of the brain is able to contribute to emotional content of language, so dysfunction of areas approximating to Broca’s and Wernicke’s result in aprosodias, which causes…..

Answer 22

which causes robotic or monotonic speech patterns

Question 23

Congenitally deaf patients with damage approximating to _____ brain language centres show signing deficits and comprehension deficits.
Those with damage to the ______ brain areas lack emotional colouring in their signing

Answer 23

Congenitally deaf patients with damage approximating to left brain language centres show signing deficits and comprehension deficits.
Those with damage to the right brain areas lack emotional colouring in their signing

Question 24

Hemispheric dominance:
Writing hand?
Language production / speech comprehension?

Answer 24

NOTE: Not all cortical functions are bilateral e.g. language processing.

•Most RIGHT handed people (95%) have a dominant LEFT hemisphere
(Left handed people are more likely to have a dominant right hemisphere)

Language is produced and speech comprehended by the DOMINANT side of the brain (mostly the left)

Question 25

Hemispheric dominance and anaesthetics and speech relationship?

Answer 25

• One side of the brain is anaesthetized via the appropriate internal carotid and the subject tested for speech.
• If the dominant side remains awake, speech is unaffected.

Question 26

How do split brain patients prove that the left side of the brain in language production and speech comprehension?

Answer 26

A. Split brain patients cannot verbally identify objects felt behind the screen with the left hand as it is controlled by the right brain (no language), however objects in the right hand can be identified verbally
B. Split brain patients cannot verbally identify objects seen with only the left visual field as it cannot communicate with the right brain (no language), however objects seen in the right visual field can be identified verbally
In both cases however, the right brain can communicate what it knows independently by drawing (visual task) or holding up fingers (if the hidden task was counting)

Question 27

How can cortical function be confirmed and information be refined through non-invasive imaging?

Answer 27

1. Using PET (positron emission tomography)
   - Requires cycloton
   - Poor spatial resolution
   - Can localise NT system
2. CT
   - Narrow bands of X-rays passed through patients
   - Transverse cut
   - Identifies white and grey mater, and ventricles
3. MRI
   - Sagital cut
   - Using radio waves given off by hydrogen atoms when tapped with radio impulses
   - Good spatial resolution
   - Variations in H density provide the tone of the image
4. fMRI (functional MRI)
   - By varying the radio pulse and magnetic field gradient parameters, grey and white matter can be filtered out revealing clear images of the vascular system. Variations of this allow monitoring of blood flow
   - Works by imaging blood flow based on amount of haemoglobin / oxyhaemoglobin detected within an area.