Biopsychology advanced info

Question 1

AO1: Localisation of function

Outline what is meant by localisation of function

Answer 1

the principle that specific functions such as language, memory hearing) have specific locations within the brain

Question 2

AO1: Localisation of function

Outline the role of the motor, somotorsensory, visual and auditory centres

Answer 2

The brain has two hemispheres, the right and left.

• The cortext is further divided into four lobes
• These are frontal lobe, temporal lobe, occipital lobe and paratneial lobe

Auditory cortex
Found near the temporal lobe
Its role is to control auditory information. Damage may produce hearing loss
Somatosensory cortex
- In the parietal lobe, it is separated from the motor cortex by the central sulcus. Responsible for sensory information from skin
Motor cortex
- found in the frontal lobe and is contralateral
-controls muscle movement
Visual cortex: part of occipital lobe and receives and processes viusal information

Question 3

AO!: Localisation of function

Outline the role of language centres in the brain

Answer 3

Brocas area: Situated in left frontal lobe. After studying patients with similar language deficits, an example being Tan who could only express one syllable ‘tan’. Damage can lead to Broca’s aphasia (speech can sometimes lack fluency etc.

Wernickes area: Doscoreved by german neurolgist. Situated In left temporal lobe and is responsible for being able to understand speech.Damage to this area can lead to wernickes aphasia, which is when there is no problem producing language but difficulty it. The language produced is fluent but meaningless

Question 4

Evaluation of localisation of function:

There is supporting evidence from case studies

Answer 4

Strengths
Case studies like show how the loss of certain functions is due to damage caused in that area
-for example: The case of Gage suggests that personality and temperament are located in the frontal lobe. Damage to this area of the brain led to a negative change in Gage’s characters
Suggests that damage to certain areas of the brain show some functions are localised
Counterpoint: Gage, people’s observations of his change may have been subjective, also Early studies of brain damage especially were poorly controlled and lack the objectivity of later brain scans.
Therefore studies supporting earlier studies supporting localisation may lack validity

Question 5

AO3 : Evaluation of localisation: evidence for neurosurgery

Answer 5

Strength
P: damage linked to mental disorders
E: Dougherty et al found 30% of 44 people had met criteria for a full recovery
14% were partial when undergoing cingulotomy
Success shows that behaviours may be localised

Question 6

Evaluation of localisation of function brains scans

Answer 6

Strength
Point: supports everyday functions are localised
E: buckner and Peterson found semantic and episodic memories are in different parts of prefrontal cortex
E: shows how parts of everyday life are localised, futher support from case studies
L:

Counterpoint: Lashley found that higher cognitive processes such as learning are not localised and memory are not localised. By the way he removed parts of rats brains and made them do a maze

Question 7

AO3: Conflicting evidence about the role of language centres

Answer 7

Dronkers et al. (2007) re-examined the preserved brains of two of Broca’s patients, Louis Leborgne (Tan) and Lazare Lelong.
-MRI imaging in order to identify the extent of any lesions in more detail.
The MRI findings revealed that other areas besides Broca’s area could also have contributed to the patients’ reduced speech abilities.
-although lesions to Broca’s area alone can cause temporary speech disruption, they may not result in severe disruption of spoken language.
-This study suggests that language and cognition are far more complicated and may involve networks of brain regions rather than being localised to specific areas

Question 8

AO1: Hemispheric lateralisation

Outline hemispheric lateralisation

Answer 8

hemsipheric laterlisation: Each hemisphere of the brain is specialised to perform different functions
-In language the two main centeres are in the lef hemsiphere so they are lateralsied
however, some functions like vsison and motor are not lateralsied.
-The motor cortex is contralateral because the RH controls the left side of the body and the LH controls movement on the right
-Vison is Ipsilateral and contralateral (so it’s opposite and same sided.
For example light is received the left visual field and the right visual field.
The LVF of both eyes is connected to the right hemisphere and the opposite is true for the RVF.
This enables the visual areas to compare slightly different perpectives which adds depth

Question 9

AO1: Split-brain research (hemispheric lateralisation)

What is it
Who done it
What was the procedure
What was the finding

Answer 9

What is it?
Surgical procedure to reduce epilepsy
When you cut corpus colosseum

Who done it
Sperry conducted a study on patients who had this done

Procedure

• 11 people were studied
• image was shown to a Ppts RVF and the same or different image would be shown to LVF. Participants were asked to pick up the image, say what the image was etc

Findings
When image was shown to RVF (linked to LH) ppt could describe what was seen but not when shown in LVF (linked to RH) because language centres are located in LH. Often they would say there’s nothing there

Ppts could select the object when it was shown LVF. They could select objects using left hand linked to RH.

Conclusion
Show how functions are lateralised
And how LH verbal and RH silent but emotional

Question 10

evaluation of lateralisation

Connected brains and Cp that RH is syntesier and :LH is analyser

Answer 10

Fink et al used PET scans to identify parts of brain that were active during a visual processing task
When looking at pictures of a whole forest RH was more active
When asked to focus on finer details LH tended to dominate
Suggests lateralisation is a feature of a connected brain as well as as split brain

CP Limitation is the idea that RH is synthétiser and LH is analyser may be wrong
Nielson et al suggests that people don’t have a dominate side
Analysed brain scans of over 1000 people and did find that people used different hemispheres for different tasks
But no evidence of a dominant side (so a mathematicians brain or an artists brain)

Question 11

AO3: Lateralisation can be adaptive, CP: neural plasticity can also be seen as adaptive

Answer 11

Having a lateralised brain can be adaptive as two tasks can be performed simultaneously with greater efficiency
Rogers found that ‘lateralised chickens’ could find food whilst watching for predators but normal couldn’t
However neural plasticity could be seen as adaptive
Some functions can be taken over by non specialised areas. Language may switch sides (Holland et al)

Question 12

AO3: lateralisation changes with age

Answer 12

Lateralisation of function does not to stay the same throughout an ones lifetime, but changes ageing.
Lateralised patterns found in younger individuals tend to switch to bilateral patterns in healthy older adults.
Szaflarski et al. (2006) found that language became more lateralised to the left hemisphere during childhood but after the age of 25, lateralisation decreased with each decade of life.

Question 13

Evaluation of split brain research

Support for split brain research

Answer 13

Gazzinga showed split brain Ppts perform better than connected ones on certain tasks
For example they were faster at identifying the odd one out.
In normal brain LH cognitive strategies are watered down by RH (Kingstone)
-supports sperry findings of left and right brain

Question 14

Evaluation of split brain research

Hard to generalise findings

Answer 14

-Andrew says that many studies on split-brain research had 1 to 3 participants
as a result, casual relationships are hard to establish
Although in Sperry’s research behaviour was compared to a control group
None of the Ppts had epilepsy which was a major confounding variable
This means that unique features may have been due to the epilepsy

Question 15

AO1: Plasticity

What is plasticity and why do we need it as humans

Answer 15

• Plasticity is how the brain adapts to change as a result of experience or new learning
• at the ages of 2 and 3 there are 15,000 connections were synapse, but as we grow older those connections are strengthened or deleted and this is known as synaptic pruning
• Our brain adapts because we need to learn new skills as result of developmental changes, due to direct trauma to the area of brain or due to indirect trauma such as a stroke

Question 16

AO1: Plasticity

Outline the findings of the key study into plasticity

Answer 16

Maguire et al
Found significantly more grey matter in posterior hippocampus of London taxi cab drivers than in a matched control group
Also found longer they been in job the more different hippocampus was

Supporting evidence
Draganski: took brain images of med students before and after exams and found changes in brains occurred three months after exams as a result of learning

Question 17

AO1: Plasticty

What is functional recovery and what are the different types

Answer 17

• Functional recovery is when Healthy areas of brain compensate for lost neuronal pathways after trauma
• neuroscientist say this can happen quickly after trauma which is called spontaneous recovery but then slow down after, after this point patients may require rehbaliative treatment
• This can happen in a variety of different ways for example

-Axonal sprouting: growth of new nerve endings which connect undamaged nerve cells to form new neuronal pathways

Denervation supersensitivity: occurs when axons do a similar job but become aroused to higher level to compensate for ones lost (can be negative and cause pain)

Recruitment of homologous areas: Specific tasks can be performed but by other parts of the Brain. For example if Broca’s area was damaged (left hemsohere) then the right hemisphere would compensate for this

Question 18

Evaluation for plasticty

There is supporting evidence from animal studies

Answer 18

Research support from animal studies
Kempermann et al. (1998) suggested that an enriched environment could alter the number of neurons in the brain.
Compared neurones of rats in laboratory and rats in complex environments
Found rats in complex environments showed an increase in neurons in the hippocampus,
This shows evidence of the brain’s ability to change as a result of experience, which supports idea of plasticity

Question 19

Evaluation for plasticity: Negative plasticity

Answer 19

P: negative behavioural consequences
E: Médina et al found that adaption to prolonged drug use leads to poorer cognitive function in later life and a risk of dementia
E2: phantom limb syndrome, 60-80% of amputees known to develop phantom limb syndrome, people develop pain due to cortical reorganisation in the somatosensory cortex (Hirstein)
E: shows how brains adaptions may not always be functional and can result in pain, or negative implications in later life

Question 20

Evaluation for plasticity: Age

Answer 20

P: life long
E: bezzola et al found 40 hours of golf training produced changes in neural representation. Fmri showed increased motor cortex
E: shows how this gives hope for people
L: demonstrates of how plasticity can be positive

Question 21

Evaluation of plasticity: real-life application

Answer 21

P: can be used to help patients recover
E: constraint-induced therapy Is used with stroke patients
E: can help healthcare professionals, makes people’s lives better, can help the economy etc
L: shows how understanding plasticity can contribute to cultivating new neuroréhabilitation techniques

Question 22

Evaluation of plasticity: supporting evidence for functional recovery

Answer 22

P: supporting evidence to for functional recovery
E: EB had a hemispherectomy on left side of brain (removed left side), fmri scans showed the RH followed a ‘left- like blueprint’ for language
E: shows how even in cases extreme trauma the brain can recover

CP: could argue things like age being a factor as children recover quicker
Elbert et al.
Found that the capacity for neural reorganisation is much greater in children than in adults

Question 23

Evaluation of plasticity: individual differences in recovery

Answer 23

P: limitation as level of education can affect recovery rates
E: schinder et al found more time people were in education the more cognitive reserve they had, greater chance of disability free recovery
CP: can be damaging to people’s recovery rates,
40% with DFR had 16 years of education
Link: implies people with less CR less likey to recover

CP: socially sensitive research, people may lose hope in recovering due to research like this (may create self fulfilling profecy) also could lead to people in healthcare spending less effort with people with lower cognitive reserves

Question 24

What is post mortum dissection (AO1) and what are the advantages and disadvantages of it (A03)

Answer 24

What is it?
When you dissect brains of people who suffered trauma and mental disorders and compare them to neurotypical brains. Example brocas area

Advantages

• Spatail resolution: can study brain in microscopic detail down to neurons
• technique has significant historical development of psychs understanding language centers
• able to see deep brain structures like hypothalmus

AO3

Harrison (2000) claims that post-mortem studies have played a central part in our understanding of the origins of schizophrenia.
-suggests that as a direct result of post-mortem examinations, researchers have discovered structural abnormalities of the brain and found evidence of changes in neurotransmitter systems, both of which are associated with Sz

Disadvantage
-Problem with causation, after death means that you can’t see the brain in action, hard to make a correlation to damage in brain to behaviour seen in life. There also may be confounding variables that caused a change in brain structure like drugs

Ethical issues: people may not be able to provide consent (like HM )

Question 25

What is fMRI and what are the advantages and disadvantages

Answer 25

What is it
can detect blood flow in brain. When doing a task there will be more blood flow to part of brain that controls it (haemodynamic response)
This then produces a 3D image showing parts of brain involved

Advantages

• Has good spatial resolution, so it can identify areas of brain involved when doing a task
• non invasive as it uses magnets, so better than PET scans, beneficial to econmey as people can recover quicker

Disadvantages

• low temporal resolution: 1 image can be taken every few seconds, so it would be hard to study brain processes that are very fast
• as it only measures blood flow, it cannot tell you what individual neurones are involved, so hard to tell what’s being shown, may be misinterpreted
• machine is expensive to build and operate, EEG is cheaper and captures more

Question 26

What is an EEG and what are the advantages and disadvantages

Answer 26

What is it
an electroencephalogram, you were a cap with electrodes that measures activity. EEG readings are used In sleep studies and can detect Alzheimer’s and epilepsy

Advantages

• has good temporal resolution
• Has medical applications as it can diagnose epilepsy and Alzheimer’
• non invasive as there are no instruments inserted into brain
• cheaper than fMRI and is able to use in experiments when subjects are moving

Disadvantges

• lack of spatial resolution: only detects activity of cortex and not brain structures deep within
• Lack of spatial resolution hard to pinpoint exactly which area is producing activity. Cannot notice differences in activity between 2 areas near each other
• uncomfortable for ppt, which could result in a reading that is unrepresentative due to the discomfort triggering a result

Question 27

What is an ERP and what are the advantages and disadvantages

Answer 27

What is an ERP
ERP’s are small voltage changes in the brain triggered by specific events or stimuli measured using an EEG. Stimulus is shown repeaditly as voltages can be hard to pick out from electrical activity of brain.

Advanatages

• Allows for changes to the stimulus can be directly recorded, as there is a measure of neuronal activity
• Good temporal resolution
• non invasive

Disadvantages

• only monitor activity in outer layers of brain so poor spatial resolution
• hard to control variables electrical activity may not even be due to stimulus
• lack of standardisation in methodology