Unit 3: Cognitive Processes

Question 1

What is aphasia?

Answer 1

Aphasia is the impairment of language caused by damage to the brain (usually stroke).

Question 2

What is Broca’s aphasia?

Answer 2

Broca’s aphasia is a result from damage to Broca’s area (located in the left frontal lobe) and often surrounding areas that leads to difficulty in expressing messages in words or sentences but the ability to comprehend speech is largely unaffected. Typically, little speech is produced and what is tends to be slow, generated with considerable effort and poorly articulated.

Question 3

What is the corpus callosum?

Answer 3

The corpus callosum is the thick band of about 200 million nerves fibres connecting the right and left hemispheres

Question 4

What is our left visual field?

Answer 4

Our left visual field is the visual stimuli on the left hand side of the stationary point that the person’s eyes are fixated on.

Question 5

What is the optic chiasm?

Answer 5

The optic chiasm is the point at the base of the forebrain where the optic nerves from each eye meet and cross over.

Question 6

What is the optic nerve?

Answer 6

The optic nerve is the two tracts of neurons that transmit visual information from the eyes to the occipital lobes of the brain

Question 7

What are photoreceptors?

Answer 7

Photoreceptors are w layer of specialised nerve cells that detects visual stimuli. They make up the retina located at the back of the eye and converts (transduces) visual light energy (electromagnetic radiation or light waves within our visual spectrum) into electrochemical energy (nerve impulses).

Question 8

What is pseudoneglect?

Answer 8

Pseudoneglect is a tendency to display a leftward attentional bias (the left side of space tends to be looked at for longer than the right) that is found in most normally functioning people.

Question 9

What is a retina?

Answer 9

A retina is a layer of photoreceptors located at the back of the eye that detect visual stimuli

Question 10

What is a right visual field?

Answer 10

A right visual field is the visual stimuli on the right hand side if the stationary point in which a person’s eyes are fixated.

Question 11

What is spatial neglect?

Answer 11

Spatial neglect is a disorder in which the person affected systematically ignores stimuli on one side of their body. Spatial neglect occurs after brain damage usually in the posterior region of their right parietal lobe and results in the person ignoring stimuli on their left side.

Question 12

What is split brain?

Answer 12

Split-brain occurs after brain surgery in which the corpus callosum is severed. The two sides of the brain are still connected at the subcortical (deeper) level but the two hemispheres are separated and cannot communicate with each other

Question 13

What is Wernicke’s aphasia?

Answer 13

Wernicke’s aphasia results from damage to Wernicke’s area, located in the left temporal lobe near the parietal lobe boundary, that causes difficulty in understanding written and spoken language and producing written and spoken language that makes sense to others. Speech is fluent but does not make sense.

Question 14

Which type of aphasia is also known as expressive aphasia?

Answer 14

Broca’s aphasia

Question 15

Which type of aphasia is also known as receptive aphasia?

Answer 15

Wernicke’s aphasia

Question 16

Which type of aphasia is also known as fluent aphasia?

Answer 16

Wernicke’s aphasia

Question 17

What are the characteristics of Broca’s aphasia?

Answer 17

Non-fluent speech
Partial or complete loss of the ability to recall names
Difficulty finding and naming the right words
Words may be mispronounced
Speech lacks grammar (usually only nouns and verbs are spoken)
Difficulty with writing
Mild comprehension difficulties (words other than nouns and verbs can be ignored in sentences)

Question 18

Why can some patients with Broca’s aphasia sing and swear with relative ease?

Answer 18

These phrases are typically spontaneous or well-memorised and require little, if any, conscious effort

Question 19

Why is the the term receptive aphasia inaccurate?

Answer 19

The difficulty is not just limited to understanding language. Their speech may be fluent but what they say does not make sense.

Question 20

What are the characteristics of Wernicke’s aphasia?

Answer 20

Speech is fluent
Partial or complete loss of the ability to recall names
Nonsense words are used
Difficulty understanding both written and spoken language
Difficulty producing written and spoken language that makes sense to others

Question 21

What are some limitations to aphasia case studies?

Answer 21

Our brains are unique and the precise location of Broca’s and Wernicke’s area varies (sometimes considerably) between people
Brain scans have revealed that many areas of the brain are associated with language use
The extent of the brain injury varies between people, and is often widespread and affects several areas of the brain so the effects on language will be different in different peopl

Question 22

What part of the brain is usually damaged if a person is suffering from spatial neglect?

Answer 22

Posterior region of the right parietal lobe

Question 23

Who pioneered the work in split-brain studies?

Answer 23

Roger Sperry and Michael Gazzaniga

Question 24

What is the procedure of split-brain studies?

Answer 24

1. Split brain patients are presented with words to their left or right visual field and asked to report what they had seen
2. Split brain patients are presented with different words on each side of the screen at the same time and then asked to report what they had seen
3. Split brain patients are presented with a picture of an object to their left or right visual field and asked to verbally identify the object or reach under the screen and select the object by touch

Question 25

What happens when split brain patients are presented with words to their right or left visual field and asked to report what they had seen?

Answer 25

When words are presented to the right visual field and therefore processed in the left hemisphere, patients were able to read and report the words verbally.
When words were presented to the left visual field and therefore processed in the right hemisphere, patients were unable to report the words verbally. They were able to select the item by touch from behind the screen with their left hand but were unable to say why they had selected the item.

Question 26

What happens when split brain patients are presented with different words in each side of the screen at the same time and then asked to report what they had seen?

Answer 26

The patients are able to read and verbally report the word presented to the right visual field (processed in left hemisphere)
The patients were unable to verbally report the word presented to the left visual field (processed in the right hemisphere)

Question 27

What happens when split brain patients are presented with a picture of an object to their right or left visual field and asked to verbally identify the object or reach under the screen and select the object by touch?

Answer 27

When a picture, say a hammer, was flashed to the left visual field (right hemisphere), the patient was unable to verbally name the object but could grasp the hammer with their left hand. The patient often denied seeing anything at all.
When a picture, say an apple, was flashed to the right visual field (left hemisphere), the patient could easily name it verbally.

Question 28

What could be concluded from Sperry and Gazzaniga’s split-brain studies?

Answer 28

The left hemisphere can identify words and picture and name them
The right hemisphere can identify and process words (and identify pictures by touch) but cannot name them
The left hemisphere appears to make the executive decision concerning whether an item was present or not

Question 29

Mandy fell off her bike and suffered some mild brain damage. Doctors tested her and found that Mandy could pronounce the word ‘accident’ but she was unable to give a meaningful verbal description of her accident.
Which part of Mandy’s brain was affected?

Answer 29

Wernicke’s area

Question 30

What structures are found in the medial temporal lobe?

Answer 30

Amygdala

Hippocampus

Question 31

Which part of the brain contains almost three-quarters of the brain’s total neurons?

Answer 31

Cerebral cortex

Question 32

Memory of sounds of words is found in what section of the brain?

Answer 32

Wernicke’s area

Question 33

Spatial neglect is usually caused by damaged to the association areas of which two lobes?

Answer 33

Frontal and parietal