🟢 Biopsychology - Localisation of Function

Question 1

What is localisation of brain function

Answer 1

Certain areas of the brain have particular functions

Question 2

What is the outer layer of both hemispheres called and how thick is it

Answer 2

Cerebral cortex, 3mm thick

Question 3

Areas of the brain to remember

Answer 3

Motor, somatosensory, visual, auditory and the language centres (brocas and wernickes)

Question 4

What was franz gall’s theory

Answer 4

Theory of phrenology, looking at the structure of the skull to determine a persons character

Replaced by localisation of function

Question 5

Where is the motor cortex located

Answer 5

Back of the frontal lobe

Question 6

Responsibility of the motor cortex

Answer 6

Generation of voluntary motor movements

Question 7

Is the Motor cortex on both hemispheres

Answer 7

Yes

Mortar cortex on right controls muscles on left side of the body. Motor cortex on left controls muscles on the right side of the body

Question 8

What can damage to the motor cortex cause

Answer 8

Loss of control over fine movements

Question 9

Arrangement of motor cortex

Answer 9

Different parts of the motor cortex controls different parts of the body, these are arranged logically. For example the region controlling the foot is next to the region that controls the leg. Meaning of damage occurs in mc, may only damage particular part of the body

Question 10

Where is the somatosensory cortex located

Answer 10

In the parietal lobe, next to motor cortex

Question 11

Role of somatosensory cortex

Answer 11

Detects sensory events from different regions of the body

Question 12

What separates the motor area and the somatosensory cortex

Answer 12

‘Valley’ called central sulcus

Question 13

Process used by the somatosensory cortex

Answer 13

Uses sensory information from the skin to produce sensations such as touch pressure, pain, temperature which is then localised to specific body regions

Question 14

How does the amount of somatosensory area in a particular body part affect sensivity

Answer 14

The amount of somatosensory area devoted to a particular body part denotes its
sensitivity. For example receptors in our face and hands occupy over half of the
somatosensory area.

Question 15

Is the Somatosensory cortex in both hemispheres

Answer 15

Yes, The cortex on one side of the brain receives sensory info from the opposite side of
the body

Question 16

Where are visual centres located

Answer 16

Back of brain in occipital lobe

Question 17

Role of visual centres

Answer 17

Process visual information

Question 18

Process of processing visual information

Answer 18

1. Begins at Retina, light enters and strikes the photoreceptors
2. Nerve impulses from retina travels to areas of the brain via the optic nerve
3. Some travel to areas of the brain involved In coordination of circadian rhythms . Most terminate in the thalamus which acts at a relay station passing info to visual cortex

Question 19

Information about visual fields and cortex

Answer 19

Each eye sends visual information from the right visual fields to the left visual cortex and then from the left visual field to the right visual cortex

Question 20

Does the visual cortex contain different areas

Answer 20

Semantic and episodic memories reside in died

Question 21

Where are the auditory centres located

Answer 21

In temporal lobes on both sides of the brain

Question 22

Process of processing auditory information

Answer 22

Begins in cochlea in inner ear, sound waves are converted to nerve impulses. Pit stop at the brain step where basic decoding happens, then onto thalamus which acts as a relay station and carries out further processing of auditory stimulus. Then via the auditory nerve to the auditory cortex. Sound has already been largely decoded by this point and in the auditory cortex it is recognised and results in an appropriate response

Question 23

What does damage to the auditory centre causes

Answer 23

Produce partial hearing loss, the more extensive the damage, the more extensive the hearing loss

Question 24

One case study for the localisation of function

Answer 24

Phineas Gage (1848)

Question 25

Who was Phineas gage and what was his accident

Answer 25

Foreman of a railway construction gang. On September 13th 1848 an accidental explosion of a charge he has sent blew his tamping iron through his head. The tamping iron was 3 feet 7 inches long and weighed 13 1/2 pounds. Went in point first under his left cheek bone and completely out through the top of his head. Landing about 25 to 30 yards behind him

Question 26

Why was Phineas gage Significant?

Answer 26

First patient from whom we learned something about the relation between personality and the function of the front parts of the brain.

Question 27

Characteristics of Phineas gage before the accident

Answer 27

- well capable and efficient foreman - well balanced - shrewd, smart businessman - sociable

Question 28

Characteristics of Phineas gage after the accident

Answer 28

-, disrespectful - impatient and stubborn - unable to create and stick to future plans - “no longer gage”

Question 29

What does the Phineas gage case study show

Answer 29

The localisation of function, how different functions. Damage to the frontal lobe affected his decision-making and social interactions, but other functions (like movement and memory) remained intact.

Question 30

Study against localisation of function

Answer 30

Karl Lashley (1950)

Question 31

Conclusion of the Karl Lashley study

Answer 31

Higher cognitive functions such as processes involved in learning are not localised but distributed in a more holistic way in the brain

Question 32

Process of Karl Lashley study

Answer 32

Lashley trained rats to navigate mazes, then lesioned (damaged) different areas of their brains to see if memory was lost. No single area was responsible for memory loss, suggesting that memory is distributed across the brain.

Question 33

Limitations of Lashley research

Answer 33

He only studied rats so his findings make not be applicable to humans. Later studies showed that memory functions are localised (tulving)

Question 34

Limitations of Gage’s case study

Answer 34

1. Lack of scientific control: no control group to compare his behaviour before and after, report on accounts rather than observations 2. No brain scans: damage may have been less extensive than originally thought 3. Some same that Gage recovered and later lived a relatively normal life 4. Small sample size, findings cannot be generalised to everyone

Question 35

What did tulving et al (1994) reveal

Answer 35

Semantic and episodic memories reside in different parts of the prefrontal cortex

Question 36

What is the Broca’s area

Answer 36

An area of the frontal lobe of the brain in the left hemisphere , responsible for speech production

Question 37

What is the wernicke’s area

Answer 37

An area of the temporal lobe, in the left hemisphere responsible for language comprehension

Question 38

Who was Paul broca

Answer 38

1880s Surgeon who identified area in the left frontal lobe responsible for speech production

Question 39

What does damage to the Broca’s area cause

Answer 39

Broca’s aphasia

Question 40

What is Broca’s aphasia

Answer 40

Trouble with speech production, speech consists of small simple sentences, mainly verbs and nouns. Reading and writing not affected

Question 41

Paul Broca’s research

Answer 41

Treated a patient called ‘Tan’ who was unable to speak other than this one word but didn’t understand language. In 1861, through a post-mortem examination, Broca discovered that Tan had a lesion in the left cerebral hemisphere caused by syphilis. This area of the brain became known as Broca’s area Also studied 8 other patients who had similar language deficits along with damage in their left and right frontal hemisphere. Found damage in left hemisphere had problems with speech, right hemisphere had problems no problems with speech

Question 42

Where is the wernickes area

Answer 42

Temporal lobe on the left hemisphere only

Question 43

Dronkers et al 2007 study

Answer 43

VS LOCALISATION OF FUNCTION Conducted MRIs scans on Tan’s brain, to try to confirm Broca’s findings. Although lesion in Broca’s area, there was evidence to suggest other areas may have contributed to the failure in speech production . Suggests that Broca’s area may not be the only region responsible for speech production and the deficits found in patients with Broca’s aphasia could be the result of damage to other neighbouring regions

Question 44

Karl Wernickes research and findings

Answer 44

Had patients who could speak but had severe difficulties understanding it. Wernicke identified an area in the temporal lobe as being responsible for language comprehension • Patients who have Wernicke’s aphasia would often produce nonsense words (neogogisms) as part of the content of their speech. Wernicke proposed that language involves separate motor and sensory regions located in different cortical regions. The motor region, located in Broca’s area, is close to the area that controls the mouth, tongue and vocal cords. The sensory region, located in Wernicke’s area, is close to regions of the brain responsible for auditory and visual input.

Question 45

What is wernickes aphasia

Answer 45

Trouble with speech comprehension. Can’t produce meaningful sentences but can string words together but why they say is nonsensical

Question 46

Turk et al 2002

Answer 46

patient JW who suffered damage to the left hemisphere but developed the capacity to speak in the right hemisphere . Eventually leading to the ability to speak about the information resented to either side of the brain. Suggests that perhaps localisation is not fixed and that the brain can adapt following damage to certain areas