11/01/20 psychology contemporary

 Learning objectives

Define and apply at least 5 key terms

Recall an outline of the contemporary study using the APRC framework and provide the background to the study

Evaluate the contemporary study using the GRAVE framework

Work collaboratively in pairs/groups to form ideas and critique the study

Shmock et al -Brain damage in patient H.M (Henry Malaison)

Background:

Investigated a group of patients who had all experienced brain damage and loss of memory. (amnesia)

Most famous patient in the study was H.M - 1926-2002

Had brain surgery for his epilepsy in 1953 -  involved the removal of the hippocampus and suffered amnesia as a result.

Important parts to focus on H.M brain - Hippocampus, temporal lobe and amygdala

Epilepsy notes-

It is a neurological condition - affects brain and nervous system.

over 500,000 people in UK suffer from epilepsy. 1% so 1 in 100 people

Also a physical condition due to seizures, 40 types of seizures

3% of people with epilepsy will be affected by flashing lights 

H.M would recall information so long as it was in his STM, but then forgot it within seconds

Could not create new episodic memories. However, he still remembered some things from before his brain damage.

Compare H.M to other patients with similar brain damage - see if a precise link could be made between brain structure and semantic memory.

H.M underwent brain surgery in 1953 

Side effects:

He was unable to encode new LTM

Even though H.M lost his episodic memory, he still had procedural memory

Could encode new procedural memories (learnt to play tennis but he couldn't remember being taught it)

Hippocampus - declarative memory

His brain was preserved for future studies

14 patients in total - matched pair designs (age and education)

Each healthy person paired with damaged brain patient

They all had different types of brain damage

3 (including him) had brain damage to the hippocampus (part of the medial temporal lobe or MTL) from surgery or other injuries

3 had brain damage from viral infections (herpessimplex encephalitis) and their brain damage was more widespread - these were called the MTL+ group

8 of them were controls who were healthy volunteers with no brain damage. They were matched with the patients in terms of age (70s) and education.

One of the probems with studying 'lesions' is that patients usually have lesions in several parts of the brain not just one.

The patients with viral brain damage had more extensive lesions than the patients like H.M who had received surgery in just one part of the brain, the hippocampus

H.M had more widespread lesions than the other MTL but not as widespread as the MTL+ patients.

Brain lesions - any type of abnormal tissue in or on brain tissue

Hippocampus and epilepsy-

lying in the middle of the brain

Small organ located within the brains medial temporal lobe (MTL)

Forms an important part of the limbic system - region that regulates emotions.

If the hippocampus is damaged it can cause epilepsy in some people.

Epilepsy is not just one condition, but a group of many different 'epilepsies' with one thing in common: a tendency to have seizures that start in the brain.

Causes - 

different epilepsies are due to many different underlying causes. The causes can be complex, and sometimes hard to identify. A person might start having seizures because they have inherited epilepsy from one or both parents, a new change in a person's genes, a structural change in a person's brain or changes to the brain from certain conditions.

Facts and statistics - 

Over half a million people with epilepsy in the UK, so around 1 in 100 people.

Other conditions that can look like epilepsy include fainting, very ow blood sugar in some people being treated for diabetes

Greek philosopher Hippocrates (460-377 BC) was the first person to think that epilepsy starts in the brain

one in 20 people will have a one off epileptic seizure at some point in their life

one in 50 will have epilepsy at some point in their life

around 87 people are diagnosed with epilepsy everyday

Myths- 

flashing lights causes seizures in everyone with epilepsy

you can restrain someone during a convulsive seizure and put your finger in their moth

the only side effects of a seizure are tiredness and being confused

Diagnosing -

Doctors gather lots of different information to access the causes of seizures

Testing - 

brain scans

MRI

ECG

Medial temporal lobe - MTL

Structures that are critical for long term memory include the hippocamous

medial - closer to the midline 

lateral farther away from the midline

APRC

Aim - 

To find out if semantic TM is linked to a particular part of the brain

If so, patients with lesions in that part of the brain should underperform at tests of semantic LTM.

Shmolck focused on damage to the medial temporaral lobe (MTL) and the hippocampus and looked in detail at H.M

Purposes of study - 

To assess the relation between test performance and the extent of damage to lateral temporal cortex and:

to determine whether any aspects of H.Ms performance were unique among the patients tested - Heike Schmolck

IV-

3 patients with damage to hippocampus/MTL only

3 patients with damage to MT and the temporal cortex too (THE MTL+ GROUP)

Control group with no brain damage

In addition, Shmolck used different types of cognitive tests on the patients. The type of cognitive test is repeated measures design

Since H.M also had more widespread brain damage than the other hippocampus 

DV- 

Scores on 9 separate tests of semantic LTM

Methodology-

14 pps

8 male controls

2 patients with lesions limited to the hippocampal formation (amnesic patients with damage limited to the hippocampal formation (HF)

Procedure - 

9 tests for semantic LTM functions. There were 8 catergories (6 in each)

These pictures were grouped in sixes - 

6 domestic land animals 

6 foreign land animals

6 water creatures 

6 birds

6 electrical household items

6 nonelectirical household items

6 vehicles

6 musical instruments

all were based on a set of 48 drawings, half of animals and half of objects

Some examples 1/4- 

pointing to picture (cue name)

Pps were given the name of each of 48 items as a cue and were asked to identify the appropriate picture from among eight pictures in the same catergory.

2/4-

category fluency -

PPs were asked to give as many examples as possible from each of the 8 categories within a minute

3/4 -

category sorting-

PPs given all 48 pictures and asked to sort them into living or man made

Then they sorted the 24 items from each of these two categories into narrower categories

- sory the living items into land animas, birds, or water creatures

- Sort the manmade things into household items, vehicles etc

4/4 - 

Definitions- 

PPs were shown the picture of each of the 24 least common items and asked to define

A line drawing of the item was in view

Additional tests -

Dr Shmock aso used additional tests that are used with dementia patients. for example..

Procedure - recording and checks-

PPs were tape recorded and their responses transcribed (typed up)

.....

Results-

1/3 -

Controls got all the answers right when asked to point to the picture of a names object (as did those with hippocampus damage) only HM scored 98% for living creature and 100%

2/3 -

MTL+ patients performed badly in most of the tests including when pps:

were shown a picture and asked to name it

were given a verbal description of an object and has a name on it

3/3 - 

MTL+ patients 

........

Conclusions-

Clear relationship between how well the PP did and damage to the lateral temporal cortex (particularly for HM and the 3 MTL+ patients

Seems

....