Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Psychology All Papers Revision > Biopsychology > Flashcards

Biopsychology Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Psychology flashcards Psychology 101 flashcards GRE® Psychology flashcards
1
Q

What is the nervous system?

A

A network of cells in the human body, the body’s primary internal communication system.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the function of the nervous system?

A

To collect, process and respond to information from the environment. It controls organs and cells in the body.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the CNS made up of?

A

The brain and spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the PNS made up of?

A

Autonomic nervous system——> sympathetic branch and parasympathetic branch

Somatic nervous system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Function of the brain

A
  • Receives and processes information from the senses e.g. visual cortex processes visual info.
  • The centre of conscious awareness
  • Responsible for higher mental functions
  • Generates emotion and thoughts
  • Initiates responses
  • Stores memories
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Function of the spinal cord

A
  • Conducts signals (sends messages) to and from the brain
  • Connects nerves to the PNS
  • Controls reflex actions e.g.
    removing a hand when it touches a hot plate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Function of autonomic nervous system

A
  • Responsible for involuntary responses for vital functions e.g. breathing, digestion and the stress response, heart rate
  • Controls smooth and cardiac muscles and glands
  • ANS control centres are in the brain stem.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the function of the sympathetic branch

A

Fight or flight response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Function of parasympathetic branch

A

Conserve & restore body energy when relaxed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Function of somatic nervous system

A
  • Responsible for voluntary movements such as walking.
  • Controls skeletal muscles
  • SNS carries commands from
    (controlled by) the motor cortex.
  • Connects the CNS and the sense
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are higher mental functions

A

The human ability to take knowledge and learning and use it to create new ideas, things and concepts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Function of PNS

A

Sends messages to and from the central nervous system via neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Outside message of a neuron

A

Chemical message

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Inside message of a neuron

A

Electrical message

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the structure of a neuron

A

Dendrites
Cell body
Axon
Myelin sheath
Nodes of ranvier
Terminal button

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the function of a dendrite

A

Where neurotransmitters are found
Once the receptor and neurotransmitter bind, it causes a new electrical impulse to occur

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the function of a cell body

A

Has the nucleus which contains genetic material of the cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the function of an axon

A

Send a nerve impulse through the neuron to transmit a message to the next neuron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the function of a myelin sheath

A

Protects the axon and helps to speed up the transmission of the message

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the function of nodes of ranvier

A

Speeds up the transmission of impulse by forcing it to jump across the gaps along the axon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the function of a terminal button

A

End of a neuron
Sends the information through to the next neuron through the release of neurotransmitters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Where is the sensory neuron located, what is its function and what is the structure

A

Location:
The PNS in clusters known as ganglia

Function:
These send information from the sense towards the brain
Receptors found in eyes, ears, tongue, skin

Structure:
They have long dendrites and short axons
Cell body is in the middle of the axon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Where is the relay neuron located, what is its function and what is the structure

A

Location:
In the brain and the visual system and spinal cord
Found in the CNS

Function:
Carry nerve impulses between neurons allowing sensory and motor neurons to communicate
Analyse sensations from these neurons and decide how to respond

Structure:
Short dendrites and short axon, no myelin sheath

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Where is the motor neuron located, what is its function and what is the structure

A

Location:
Cell body are found in the CNS but the long axons form part of the PNS

Function
Send information via long axons from the brain/ spinal cord through to effectors such as muscles or glands

Structure:
They have short dendrites and long axons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is the role of neurotransmitters

A

Their role is to transmit information from one neuron to another so that a person performs an action

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the process of synaptic transmission

A

Beginning:
1) action potentials are sent down the axon in the presynatic neuron until they reach the presynaptic terminal

Middle:
2) this causes neurotransmitters which are stored in vesicles and are only located in the pre synaptic neuron to be diffused into the synaptic gap
3) neurotransmitters diffuse across the synaptic gap (high to low conc) and bind with specific receptor sites that are only located on the post synaptic neuron

End:
4)once enough neurotransmitters attached there are two outcomes:
Next neuron is ready to fire an impulse depending on if inhibitory or excitatory effect
OR
Neurotransmitters are recycled in presynaptic neuron in a process called reuptake

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Excitatory neurotransmitters e.g. adrenaline

A

1) When excitatory transmitter binds to post synaptic receptor the post synaptic cell becomes positively charged
2) more likely to fire an impulse down the axon
3) increases the brain activity in the CNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Inhibitory neurotransmitters e.g. serotonin

A

1) when the inhibitory neurotransmitter binds to the post synaptic receptor sites the post synaptic cell becomes negatively charged
2) prevents the likelihood that the post synaptic cell will fire and impulse
3) this decreases the brain activity in the CNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is summation

A

1) This occurs when inhibitory and excitatory neurotransmitters influences are added together
2) if it is mainly inhibitory so is negatively charged and reduces the likelihood that the next neuron will fire
3) If it is mainly excitatory it becomes positively charged and the impulse will fore a impulse down the axon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Impulses only go in one direction because…

A

Neurotransmitters are only located in the pre synaptic neuron
Receptors are only present on the post synaptic neuron
High to low concentration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is a hormone

A

Chemical message released by glands into the blood stream

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What is a gland

A

An organ that secretes specific hormones for use in the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is the function of the endocrine system

A

Regulate the activity of cell and organs in the body
Slower than the nervous system but effects are more widespread and powerful
Send chemical messages called hormones which are released by glands to regulate many bodily function

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is the function of the pineal gland

A

Secretes melatonin
Which is involved in regulating the sleep wake cycle and making the person fell tired so they can be ready for sleep

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is the function of the adrenal gland

A

Release adrenaline
Which causes physiological changes involved in the flight or fight response
Such as increased blood flow to transport oxygen to the brain for rapid response planning

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is the function of the pituitary gland (master gland)

A

Secretes many different hormones that controls the functions of the other glands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What are two examples of hormones that the pituitary gland releases

A

Ovaries:
Pituitary gland releases LH and FSH which encourages ovaries to release oestrogen and progesterone to regulate the female menstrual cycle and prepare body for reproduction

Testes:
Pituitary gland releases LH and FSH which encourages testicles to release testosterone which is involved in production of sperm and male characteristics

38
Q

Which 2 parts play a major role in the flight or fight response

A

Autonomic nervous system ——-> sympathetic branch
Endocrine system

39
Q

What is the process of the flight or fight response

A

A stressor (stress stimuli) is identified by the hypothalamus
Activates the pituitary gland which triggers activity in the sympathetic branch of the ANS
Adrenaline is released by adrenal medulla into blood stream
Flight of fight is produced, preparing the body for sudden physical action
This produces physiological reactions such as increased respiration and reduced saliva production and digestion
This is immediate and automatic
The parasympathetic branch returns the body back to normal once the stressor has been removed.

40
Q

Flight or fight response A03:

A

Another issue is that it does not explain the stress response in females. For example, research has found that women are more likely to protect their offspring (tend) and form alliances with other women (befriend) than to fight or run away. This suggests there is a gender bias as the fight or flight response assumes that men and women respond in the same way to a threatening situation prior to this research, limiting the explanation of the fight or flight response.

One issue with the fight or flight response is that human behaviour is not limited to two responses. Some psychologists argue that the first response to danger is to avoid confrontation altogether through a ‘freeze’ response. During the response humans consider the best course of action for the threat they are faced with. This suggests that the fight or flight response does not consider other factors such as thought processes.

41
Q

What is localisation of function

A

Specific ares of the brain are specialised for certain jobs
E.g. the motor cortex is responsible for voluntary movements.
Only this area of the brain is responsible for this job.

42
Q

What is hemispheric lateralisation

A

The brain is spilt into two symmetrical halves called the left and right hemisphere.
The idea that the two different hemispheres are responsible for different mental processes
E.g. left hemisphere is responsible for language and the right hemisphere is responsible creativity ad recognition

43
Q

What is the holistic theory

A

Holistic Theory
Before investigations into localisation and lateralisation, scientists believed that ALL parts of the brain worked together when processing information

44
Q

Name all the parts of the brain and which hemisphere they are located in

A

Motor cortex - both hemispheres
Somatosensory cortex - both hemispheres
Visual cortex - both hemispheres
Wernickes area - left hemisphere
Auditory cortex - both hemispheres
Broca’s area - left hemisphere

45
Q

What is the function of the motor cortex and what happens if there is damage to this area

A

1) responsible for voluntary movements
2) each hemisphere controls the movement of the opposite side of the body

Damage:
1) loss of control of fine movements on opposite side of the body e.g picking up small objects

46
Q

What is the function of the somatosensory cortex and what happens if there is damage to this area

A

1) processes information fro the senses in the skin. 2) Such as touch, pressure, pain and temperature from all areas of the body

Damage:
1) produce problems in perceiving touch, failure to recognise object by touch

47
Q

What is the function of the visual cortex and what happens if damage is caused to this area

A

1) receives information directly from the eyes RVF- LH and the LVF-RH
2) it processes information such as colour and shape

Damage:
1) can produce blindness, hallucination or inability to see colour or motion

48
Q

What is the function of the wernicke’s area and what happens if there is damage to this area

A

1) involved with the understanding of language

Damage:
1) cause wernickes aphasia where ppl can not understand spoken language
2) or a person produces nonsense words as part of their speech

49
Q

What is the function of the auditory cortex and what happens if this area is damaged

A

1) associates with analysing speech based information such as hearing pitch and volume

Damage:
1) produce partial hearing loss or full hearing loss

50
Q

What is the function of the broca’s area and what happens when damage is caused to this area

A

1) involved in the production of spoken and written language

Damage:
1) broca’s aphasia where a person will show slow speech that lack fluency
2) or complete absence of speech
3) or short meaningful speech that requires great deal of effort

51
Q

AO3 for localisation of the brain

A

Moreover , research to support localisation of function in the brain was by Broca. He reported the case study of man who lost the ability to speak, except for one word ‘Tan’, even though he could understand language. Post mortems showed damage in one area in the left hemisphere, which is now named Broca’s area. This shows that language production is localised to one specific brain area as the theory predicts.

Research to contradict localisation of function further comes from a case study on a patient named EB. EB suffered from brain damage that resulted in the removal of his left hemisphere and therefore his language centres. Despite this, after some time EB managed to regain some of his language ability that would not be possible if the language centres were completely localised to the left hemisphere. This demonstrates that language must be in more areas than just the left hemisphere, arguing against localisation of language centres in the brain.

However both case studies lack population validity. It may not be appropriate to generalise the findings on the localisation of function to the typical population, as these are unique case studies where brain dam,age may have affected the way in which the brain functions and some individuals may be able to process language in other areas of the brain. Therefore suggesting that more research is needed with more diverse samples before firm conclusions on the localisation of language areas are possible.

52
Q

What is the left hemisphere responsible for

A

Language as the 2 main language centres located here. Broca’s area, responsible for language production and wernicke’s area responsible for speech comprehension

53
Q

What is the right hemisphere responsible for

A

Recognition of faces, places and objects and creativity and can only produce basic simplistic words and phrases but contributes to emotional context of what was being said.

54
Q

What is the corpus collosum

A

Bundle of fibres in the brain that enables corresponding regions of the right and left hemispheres to communicate

55
Q

Hemispheric lateralisation AO3

A

Research to support hemispheric lateralisation was conducted by sperry using split brain patients who had a severed corpus collosum. He found that when ppts were shown an image of an object in their RVF the patient could verbally name was at the object was however when they were presented an object in there LVF they could not name the object verbally but could identify the object by pointing at it. This supports that the brain is lateralised and that the hemispheres are responsible for different functions such as left being responsible for language abilities. Therefore, spilt brain research supports the theory of hemispheric lateralisation.

Moreover, research to contradict hemispheric lateralisation of the brain comes from a case study on a patient named EB. EB suffered from brain damage that resulted in the removal of his left hemisphere and therefore his language centres. Despite this, after some time EB managed to regain some of his language ability which would not be possible if the brain was completely lateralised. This demonstrates that language must be in more areas than just the left hemisphere, arguing against lateralisation of function in the brain.

However, the case study of EB lacks population validity. It may not be appropriate to generalise the findings on lateralisation of function to the population, as these are unique case studies where brain damage may have affected the way in which the brain functions and some individuals may be able to process language in the right hemisphere. For example some research has suggested that language is not entirely lateralised to the left hemisphere but is found in the dominant cerebral hemisphere which is usually the opposite to dominant handedness. Therefore, suggesting that more research is needed with more diverse samples before firm conclusions on the lateralisation of language is possible.

56
Q

What is split brain patients

A

Patients who have had surgery, to treat epilepsy, to cut the area that connects the two hemispheres of the brain (corpus collosum)

57
Q

Outline spilt brain research

A

Aim: to investigate the effect of severing the corpus collosum on functioning / lateralisation of function

Method: natural experiment (naturally occurring IV)

Participants: 11 individuals who has their corpus collosum severed

Procedure:
1) Ppts had to fix their gaze on a spot in the middle of a screen.
2) They were then presented with an image in either they RVF or LVF for 1/10th of a second (so not enough time to switch between visual fields)

Results:
1) Objects seen in RVF could be verbally identified. 2) Objects seen in LVF could only be identified through pointing not verbally.

Conclusion
1) The two hemispheres have different abilities and functions but only left can produce language
2) right hemisphere can recall and identify but not verbalise.

58
Q

Spilt brain research AO3

A

A strength of the research into hemispheric lateralisation is that it uses scientific methods. This is because it is based on objective and empirical techniques such as controlled laboratory settings. These are used in order to identify which hemisphere of the brain is responsible for which task, for example the split brain patients were only able to say what they saw when the image was presented to the right visual field, which suggests the left hemisphere is activated during language tasks. Arguably, this increases the overall internal validity of hemispheric lateralisation research, therefore, raising Psychology’s scientific status.

One limitation of the research is individual differences in the participants, in relation to how lateralised their brain was. The degree to which the corpus callosum was severed for each participant varied greatly with some having a greater disconnection between the two hemispheres than others. This is a weakness because the research may not be measuring the effects of lateralisation effectively which reduces the internal validity of the research.

Moreover, research to contradict hemispheric lateralisation of the brain comes from a case study on a patient named EB. EB suffered from brain damage that resulted in the removal of his left hemisphere and therefore his language centres. Despite this, after some time EB managed to regain some of his language ability which would not be possible if the brain was completely lateralised. This demonstrates that language must be in more areas than just the left hemisphere, arguing against lateralisation of function in the brain.

59
Q

What is plasticity

A

The brain’s ability to change and adapt its structures and processes as a consequence of experience and new learning

60
Q

What is synaptic pruning

A

As we age the connections that are not used as regularly are deleted and ones we use regularly are strengthened.

61
Q

Outline research investigating plasticity

A

1) Conducted by Maguire et al
2) Studied the brain of London taxi drivers
3) Found there was greater volume of grey matter in the hippocampus (responsible for spatial and navigational skills) in those who had been a taxi driver for a long time compared to those who had been taxi drivers for shorter time.
4) this difference was due to the greater knowledge of the roads which suggests the structure of their brain has been altered by their experience which is what plasticity predicts.

62
Q

What is functional recovery

A

This is a type of plasticity and refers to recovery of abilities and mental processes such as (movement or language) that has been affected as a result of brain damage or disease

63
Q

2 ways in which functional recovery works by creating a number of structural changes in the brain

A

Axonal sprouting
Recruitment of homologous areas

64
Q

What is axonal sprouting

A

The growth of a new nerve endings which connect with other undamaged nerve cells to form new neuronal pathways.

65
Q

What is recruitment of homologous areas

A

Areas from the opposite side of the brain take over the function of the damaged area of the brain e.g. if Broca’s area was damaged in the LH, the right side would carry out its functions

66
Q

What are factors that affect functional recovery

A

Use the acronym PAGES

P- perseverance - take a great deal of effort to recover from trauma. Lose function if person is not trying

A- age - younger people are more likely to recover than older individuals. As there is a deterioration of the brain in old age which can affect the extent and speed of recovery

G- gender - some research suggests that females are more likely too recover than males

E- education - more time people with a brain injury had spent in education the greater their chance of recovery

S- stress and alcohol - can make it more difficult to regain the ability to function. Links to perseverance

67
Q

AO3 for plasticity and functional recovery

A

Research to support comes from a case study on a patient named EB. EB suffered from brain damage that resulted in the removal of his left hemisphere and therefore his language centres. Despite this, after some time EB managed to regain some of his language ability, which would not have been possible if the brain was completely lateralised. This suggests that EB’s brain has experienced recruitment of homologous areas and demonstrates the brain can adapt to produce language even when the left hemisphere is not present or functioning, therefore supporting the idea of plasticity and functional recovery.

However, this research lacks population validity as the case study only involves one participant, EB who had severe brain damage. This is an issue as it may have caused unique changes in the brain that may have influenced the plasticity and functional recovery of the brain. This limits how well the research can be generalised to the wider population as different genders or age groups may experience different levels of plasticity in the brain. Thus, this lowers the external validity of the research into plasticity and functional recovery.

A strength of the research investigating plasticity and functional recovery is that it has practical applications. This is because the principles of the theory that it is possible for an individual’s brain to recover from damage through axonal sprouting has led to the development of neurorehabilitation. This is where the patient practices repeatedly using the affected side of the body e.g. an arm, whilst restraining the unaffected arm. Therefore, this is an important area of applied psychology as it helps to treat people in the real world.

68
Q

What are the four ways to studying the brain

A

fMRI
EEG’s
ERP’S
Post-mortem

69
Q

How does fMRI’s work

A

Identifying changes in oxygen levels that occurs due to brain activity in that area
When a brain area is more active more oxygen ad increase in blood flow to this area
FMRI produces a 3d image showing part of brain that are active. Called activation map
Used to identify which specific parts of the brain are active in particular mental processes

70
Q

What does spatial resolution mean and what does temporal resolution mean

A

Where specifically in the brain
How quickly you can see the brain activity occur

71
Q

AO3 for fMRI

A

fMRI is a much safer technique to measure brain activity
As it is non invasive and doesn’t use radiation to identify the difference in brain areas
Unlike the use of PET scans which uses radiation
Therefore, fMRI is a more appropriate technique to use that could reduce the risk of potential harm to individuals

fMRI have higher spatial resolution than EEG and ERP
Which is an important feature of brain scans because it can accurately identify specific brain areas involved in behaviour, depicting detail by the millimetre and providing a clear image of how the brain is localised

However, fMRI have poorer temporal resolution as there is around a 5 second time lag behind the image on the screen and the initial firing of the neuronal activity . Therefore fMRI’s may not represent moment to moments brain activity.

72
Q

How does EEG’s work

A

EEG’s is a brain scanning technique that works by:
Placing electrodes on the scalp using a skull cap
They detect small electrical changes from the activity
The electrical signals are graphed over period of time to see a persons general brain activity
EEG’s are used to detect sleep patterns and states such as sleep or arousal
Helps diagnose brain tumours and epilepsy

73
Q

AO3 for EEG’s

A

A strength of the use of EEG is that it had high temporal resolution
This enables the researcher to take a real time recording of the brain activity rather than a still image of the brain unlike the use of fMRI or post-mortem
This means that researcher can gain a more accurate measure of the brain activity.
Therefore providing a greater insight into the processes of the brain such as the activity of the brain during sleep, increasing its validity as a way of studying the brain

However a limitation of the use of EEG is that it is low in spatial resolution,
Therefore can only provide information on general activity in the brain
It cannot pinpoint exact source of neural activity that is involved in behaviour, unlike fMRI which enables a researcher to identify specific brain activity during certain mental processes
Therefore findings may be less valuable in developing understanding than by usuing alternative ways of scanning the brain such as fMRI’s.

74
Q

How does ERP’s work

A

Electrodes placed on the scalp
Shows general brain activity of a specific event
A stimulus is presented and brain activity is measured in the same way as EEG
All extraneous brain activity from the original EEG recording is filtered out leaving only responses that link to presentation of the stimulus

75
Q

AO3 for ERP’s

A

ERP’s also have high temporal resolution, especially when compared to an fMRI.
This means ERP’s can identify brain activity every millisecond so researchers can see brain activity in real time.

However ERP’s have poorer spatial resolution than fMRI as they can only detect brain activity in general brain areas rather than identify the specific location of the brain activity

It can be hard to obtain meaningful data from the use of ERP because they can be affected by external factors such as background noise
Which means that it can take many trials to obtain meaningful data as it is hard to control these other factors
This limits the internal validity of ERP’s as a means of studying the brain for a range of brain processses.

76
Q

How do post-mortems work

A

Brain of dead patient is examined and dissected to see if any abnormalities
Compare brain to brain that does not show this behaviour or mental process
Used on people with rare disorders

77
Q

AO3 for post-mortems

A

This is the only invasive way to study the brain
Which means that it is possible to get a more detailed examination of the brain than using only EEG’s or ERP’s brain scanning techniques
For example it has meant researchers have been able to study deeper areas of the brain such as hypothalamus
which has helped understand brain functioning in many different behaviours

It is hard to establish cause and effect worth post mortem studies as there are many confounding variables which cannot be easily controlled
Such as how long a person has had a particular disorder, age at time of death or whether they have received drug treatment.
Therefore it limits the internal validity of the findings of these studies and therefore the appropriateness of using post-mortem to study the brain.

78
Q

What is a biological rhythm

A

Physical, mental and behavioural changes over a period of time

79
Q

Difference between the rhythms

A

Circadian rhythm’s- cycle that lasts 24 hours e.g body temperature and the sleep wake cycle
Ultradium rhythms - cycle that lasts less than 24 hours e.g. stages of sleep which lasts approximately 90 minutes
Infradium rhythms - chelicerae that lasts over 24 hours e.g female menstrual cycle

80
Q

Describe the circadian rhythm

A

Sleep wake cycle
Controlled by the endogenous pacemaker - suprachiasmatic nucleus found in the hypothalamus

Eyes notice a change in light as it gets dark and less light is received by the retina
This sends information to the SCN which stimulates the pineal gland to release melatonin and promote sleep
When our eyes detect light (exogenous zeitgeber) the SCN is reset which maintains the sleep wake cycle to around 2r hours so that we can be in synchrony with the outside world

81
Q

AO3 for circadian rhythm

A

Research to support circadian rhythms lasting 24 hours was conducted by siffre. He isolated himself in a cage for 6 months where his biological clock (endogenous pacemaker) was able to be free running and unaffected by exogenous factors such as clocks and natural light. It was found that within a few days he had developed a consistent 25 hour cycle and continued to fall asleep and wake up ion a regular schedule. Therefore, this supports that the sleep wake cycle is a circadian rhythm which is mainly controlled by an endogenous pacemaker, the SCN, to maintain a circadian rhythm and lasts around 24 hours.

DISCUSSION: However one limitation of the research by Siffre is low population validity. It was conducted as a case study with Siffre as the only participant so it may not be appropriate to generalise findings on the sleep wake cycle beyond Siffre due to individual differences in the sleep wake cycle and circadian rhythms. For example, older people’s circadian rhythms may be slower and more easily influenced by exogenous zeitgebers, as even in one of Siffre’s later replications he found that his own circadian rhythm had slowed. Therefore, lowering the external validity of the research investigating circadian rhythms.

A strength of the research investigating circadian rhythms is that it has practical applications. This is because the basic principles of the theory, that a circadian rhythm is around 24 hours and maintained by endogenous pacemakers, has given researchers a better understanding of the negative consequences that can occur as a result of disrupting their rhythm. For example, night workers who experience shift work have a period of reduced concentration around 6am meaning mistakes and accidents are more likely. This can be used by employers to manage worker productivity, which consequently improves the economy. Therefore, this research investigating circadian rhythms is an important part of applied psychology.

82
Q

What is an infradian rhythm

A

Biological rhythms that last longer than 24 hours. One example is the female menstrual cycle that operates on a 28 day cycle

83
Q

Outline an example of infradian rhythms

A

1)The menstrual cycle is an endogenous system which typically lasts between 28-35 days

2)It begins on the first day of a womens period when the womb lining is shed to the day before her next period

3) In the brain the pituitary gland releases FSH which activates the release of oestrogen from the ovaries and causes an egg to mature

4)The increase of oestrogen increases levels of LH which promotes the release of an egg

5) Oestrogen envelops a lining of the womb and progesterone helps it to grow thicker, readying the womb for pregnancy

6)If pregnancy does not occur, the egg is absorbed into the body, the womb lining comes away and leaves the body and the cycle begins again

7) Although the menstrual cycle is mainly an endogenous system that maintains the infradian rhythm it can be affected by exogenous factors such as stress and pheromones (chemical scent given off my females and males)

84
Q

Infradian rhythms AO3

A

Research to contradict that infradian rhythms such as the menstrual cycle are mainly governed by an endogenous system was conducted by Russell. They asked a sample of women to wear cotton pads under their arm. The pads were then rubbed on the upper lip of 5 sexually inactive women.This process was repeated daily for five months. They found that 4 out of 5 women developed menstrual cycles that synchronised to within one day of the donor cycle. Therefore, suggesting that the infradian rhythm of the menstrual cycle can be affected by exogenous factors as well as controlled by endogenous factors which may influence the length of the infradian rhythm.

Discussion: However Russell’s research into the effect of exogenous zeitgebers on the menstrual cycle was a field experiment and so has low control over extraneous variables. The research took part in the participant’s natural environment, where other exogenous factors, such as light, changes in diet and stress, could also have affected the infradian rhythm. Therefore, it is difficult to establish cause and effect between the influence of pheromones on maintaining an infradian rhythm. This weakens the extent to which Russell’s research can contradict the importance of endogenous pacemakers on maintaining infradian rhythms.

However, despite the methodological flaws in infradian synchronisation studies the research findings can be explained by evolutionary psychologists. It would have been advantageous in our evolutionary past for a social group to synchronise pregnancies so that many women would be breast feeding at the same time so one mother could take over child caring for an orphaned child to improve chances of survival. Therefore, showing that synchronisation of infradian rhythms such as the menstrual cycle, is an adaptive strategy and supports exogenous factors influencing infradian rhythms.

85
Q

What is an ultradian rhythm

A

Biological rhythm that lasts less than 24 hours
Stages of sleep - lasts 90 minutes and consists of 5 stages and alternates between rapid eye movement and non rapid eye movement.
It is known as the sleep escalator, a person can experience up to 5 cycles per night that repeat in rhythmic pattern.

86
Q

What are the different stages of sleep

A

Stage 1 and stage 2 - this is a light sleep and the person can easily be woken - NREM
Stage 1 - experiences alpha waves
Stage 2 - alpha waves continue but occasional random changes in pattern called sleep spindles

Stage 3 and 4 - deep sleep - NREM
Stage 3 and 4 is knows as deep sleep or slow wave sleep
The brain waves are delta waves with lower frequency and higher amplitude.
It is difficult to wake someone at this point

Stage 5 - REM
The body is paralysed
Brain activity closely resembles that of the awake brain.
The brain produces theta waves an the eyes occasionally move around - this is called rapid eye movement
Dreams often experienced in this stage but may also occur in Deep sleep

87
Q

AO3 for ultradian rhythms

A

A strength of research investigating ultradian rhythms is that it has practical in understanding age related changes in sleep. The knowledge that growth hormone is produced during stage 4 of sleep (slow wave sleep) has been associated with sleep deficit in old age as research has found older people experience less stage 4 sleep. As a result of this research, medication and relaxation techniques have been developed to increase stage 4 sleep in older individuals and therefore, prevent some issues associated with old age such as reduced alertness. Therefore, research investigating ultradian rhythms is an important part of applied psychology.

In addition a further strength of research into ultradian rhythms is that it uses scientific methods. This is because it is based on objective and empirical techniques such as EEGs to measure brain activity and controlled lab settings. These scientifically measure the activity of the brain throughout the five stages of sleep to identify the length of rhythm and how many times the rhythm occurs throughout the duration of sleep whilst excluding extraneous variable that may affect sleep such as n Ouse and temperature. Thus, psychologists would argue that this increases the overall internal validity of research investigating ultradian rhythm, therefore, raising psychology’s scientific status

However, the research may have low ecological validity. Research on ultradian rhythms is conducted in an artificial setting and so the sleep experienced by participants in these studies may not reflect their genuine sleep patterns due to the unfamiliar surroundings and because they are attached to electrodes. This may alter the length of the ultradian rhythm, making it difficult to generalise findings to explain how ultradian rhythms work in real life

88
Q

Intro to essays on endogenous pacemaker and exogenous zeitgebers

A

Endogenous pacemakers are internal factors which help us to maintain our biological rhythms. It is also thought that are rhythms are entrained (synchronised) by exogenous zeitgebers (external factors) such as light and meal times

89
Q

What hat happens when our sleep wake cycle is disrupted?

A

Difficulty in sleeping (harder to sleep or falling asleep whilst driving)
Decreased attention which can lead to accidents
Digestive problems
Tiredness and poorer reasoning skills
Increased anxiety and irritability

90
Q

How could we maintain our sleep wake cycle?

A

Keep to local times for eating
Keep to local times for sleeping e.g. sleeping when it is dark and forcing yourself to get up when it is light.
Stimulate yourself during the day by being social and
active, such as talking and eating.
Use black out curtains at night to limit any artificial light
Not using phone later at night

Psychology All Papers Revision (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions