topic 4 - the brain and neuropsychology

label the diagram of the brain

function of the frontal lobe

important role in decision-making, problem-solving skills and impulse control

the motor cortex is located towards the back of the frontal lobe and is responsible for the voluntary movements of the human body

function of the temporal lobe

helps with hearing and understanding sound as well as creating and understanding speech

said to contain the auditory cortex (controls our hearing)

function of the parietal lobe

helps with the ability to understand the world around us (perception) and it gives us the ability to recognise faces

function of the occipital lobe

deals with our ability to see and process visual information from our eyes so that we can understand what we are seeing

function of the cerebellum

plays a vital role in movement, coordination and balance (motor skills)

takes information from different senses and combined them to coordinate behaviour

lateralisation of function

the different jobs that are done by each half of the brain

asymmetrical function

the two hemispheres of the brain are not equal in terms of what they do

role of the left hemisphere

plays a big role in the processing of language

an area in the left hemisphere known as the Broca’s area controls the production of speech

role of the right hemisphere

plays a large role in our spatial awareness

controls our ability to recognise and perceive faces

often referred to as more creative

corpus callosum

a thick bundle of nerve fibres connecting the two hemisphere of the brain so that they can communicate with each other

sex differences in brain lateralisation

there is evidence that females have a thicker corpus callosum meaning they may use both sides of their brain to do some tasks

males tend to show dominance for one hemisphere for the same tasks with more activity in one hemisphere than the other hemisphere

strengths of lateralisation as an explanation of sex differences between males and females

Harasty et al. (1997) suggested that parts of the brain that process and produce language are slightly bigger in females compared to males

Rilea et al. (2005) found that males were better at spatial tasks

the experiments conducted have strong control over extraneous variables and are highly reliable

weaknesses of lateralisation as an explanation of sex differences between males and females

Rilea et al. (2005) found that males did not always perform better than females on spatial tasks

Sommer et al. (2004) suggested that there was no strong evidence that females used both hemispheres for language tasks

neurone

a nerve cell that transmits information

synapse

a gap between two neutrons that allows messages (in the form of neurotransmitters) to pass from one cell to another

neurotransmitters

chemicals released from neurons that pass messages from one neuron to another across a synapse

synaptic transmission

when messages are passed through the nervous system from one neuron to the next

central nervous system (CNS)

made up of the brain and the spinal cord

helps the brain and body communicate with another by passing messages forwards and backwards between them

neurological damage

refers to any kind if damage to parts of the nervous system

visual agnosia

the inability to recognise things that can be seen

a person can see perfectly well but cannot understand what that are seeing

this occurs as a result of damage to the parietal lobe because it is a disorder of perception

symptoms of visual agnosia

not being able to recognise the colour of an object

not being able to recognise objects and name them

not being able to recognise places you are familiar with

prosopagnosia

the inability to recognise faces

can be caused by damage to the back of the temporal lobe known as the fusiform face area

symptoms of prosopagnosia

difficulty in identifying people from their faces

seeing all faces as the ‘same’ and not being able to tell them apart

impact of damage to the pre-frontal cortex

the pre-frontal cortex helps us control our impulses and keep our emotions balanced

if it becomes damaged, a person may become aggressive and impulsive

Adrian et al. (1997) found that murderers had less activity in their pre-frontal cortex than a normal person, making them more aggressive and impulsive

background of Damasio et al. (1994)

in 1848, Phineas Gage was working in a railway line in the USA when an explosion caused an iron rod to pass through his head

it cause serious damage to his face and the frontal lobe of his brain

his personality underwent permanent damage

before the accident, he was described as calm and responsible but after the accident, he was described as aggressive and rude

aims of Damasio et al. (1994)

wanted to build a model of Gage’s brain to figure out how the rod passed through his head

wanted to discover if any other parts of his brain had also been damaged

procedure of Damasio et al. (1994)

began by taking pictures and measurements of the skull of Phineas Gage

then they built a 3D replica model of a skull that matched the measurements of Gage’s skull

in total, 20 different entry points and 16 different exit points were tested

results of Damasio et al. (1994)

there was likely to have been damage in both the right and the left hemispheres of the frontal lobe

the damage was likely to have only affected the frontal lobe and no other parts of the brain

the iron bar would have passed through the left eye socket and upwards through the head

there was likely to have been more damage to the underlying white matter in the left hemisphere than in the right frontal lobe

the damage in both hemispheres seemed to be worse in the middle of the underside (ventromedial region)

conclusion of of Damasio et al. (1994)

the ventromedial area of the frontal lobes seems to be important for making sensible decisions and controlling our impulses around people

it also seems to be important for the control of emotions

this knowledge can be used to predict the behaviour of someone who suffers brain damage in these areas in the future

strengths of Damasio et al. (1994)

researchers were able to use modern-day technology which made the results more scientific

we can now make predictions about what changes to behaviour we might expect if someone has damaged their frontal lobes

weaknesses of Damasio et al. (1994)

based on results that were originally gather 150 years ago which may make the information inaccurate and unreliable

holistic so there is a problem in generalising the results because it can only be applied to a certain individual

background of Sperry’s (1968) study

some patients with severe epilepsy who had not responded to treatment were offered surgery to help reduce their seizures

the surgery involved cutting down the corpus callous to disconnect/separate the right and left hemispheres

aims of Sperry’s (1968) study

what effects could be seen in split-brain patients by monitoring how they processed information

procedure of Sperry’s (1968) study

group of 11 participants who had their corpus callosum cut

they were each given various tasks to test how they processed different types of information

results of Sperry’s (1968) study

tasks involving reading words or selecting objects:

when words were shown to the right visual field, the patients had no problem

when they were shown the word to their left visual field, people had trouble saying what they had seen

if a word or picture was shown to the left visual field, participants had little trouble

when the word or picture was shown to the right visual field, the participants struggled to point to the correct object

when objects were presented to each hand:

when objects were felt by the right hand, they could name the object

when objects were felt by the left hand, it was more difficult

when two different objects were given to the participant and they were then asked to find it in a pile of objects, they could only identify each item with the hand that originally held it

conclusions of Sperry’s (1968) study

each hemisphere is perfectly capable of working well without being connected to the other side

the left hemisphere seems to be better at naming items using words when they had been held by the right hand

the right hemisphere was better at identifying objects by feeling for them with the left hand

the left hemisphere controls more language abilities and the right hemisphere controls more spatial abilities

strengths of Sperry’s (1968) study

gathered a lot of detailed information which made the study more reliable

data was gathered in a reliable way

weaknesses of Sperry’s (1968) study

the sample of 11 participants is too small to generalise the results

the results lacked ecological validity because the tasks down in the lab were in an artificial environment

how has psychology changed over time?

‘born’ in 1875 when William Wundt opened a laboratory in Leipzig, Germany to study people’s thoughts

studying the brain at that time could only be done post-mortem

in 1924, Hans Berger developed the EEG as a way to measure brainwave activity in a living brain

then, the MRI and PET scans were developed to show detailed pictures of what the brain looks like or how active different parts of the brain are at different times