Biopsychology Flashcards
(121 cards)
1
Q
What is the nervous system?
A
A specialised network of cells in the human body and is our primary communication system
2
Q
What does the nervous system use?
A
Electrical signals via nerves
3
Q
Is the nervous system fast or slow?
A
Fast
4
Q
What are the two main functions of the nervous system?
A
- To collect, process and respond to information in the environment
- To co-ordinate thw working of different organs and cells in the body
5
Q
What two sub sections does the nervous system consist of?
A
- The peripheral nervous system
- The central nervous system
6
Q
What does the central nervous system consist of?
A
Brain and spinal cord
7
Q
What does the peripheral nervous system consist of?
A
The autonomic nervous system and somatic nervous system
8
Q
What is the autonomic nervous system responsible for?
A
The fight/flight response
9
Q
What is the endocrine system?
A
Works alongside the nervous system to control vital physiological processes
10
Q
What does the endocrine system use to deliver hormones to target sites in the body?
A
Blood vessels
11
Q
Is the endocrine system fast or slow?
A
It is slower and longer-lasting than the nervous system
12
Q
What are hormones?
A
Chemical messages that circulate the bloodstream, influencing different bodily processes
13
Q
What do hormones do?
A
Alter the probability of a behaviour occurring- so they influence behaviour
14
Q
What hormones does the pituitary gland release?
A
Anterior: ACTH
Posterior: Oxytocin
15
Q
What effect does the pituitary gland have on the body?
A
- Stimulates the adrenal cortex and the release of cortisol during the stress response
- Responsible for uterus contractions during childbirth
16
Q
What hormones does the adrenal gland release?
A
Cortisol, adrenaline, noradrenaline
17
Q
What effect on the body does the adrenal gland have?
A
-Located at the top of each kidney, produce hormones that help the body control blood sugar, burn protein and fat, react to stressors like a major illness or injury, and regulate blood pressure
18
Q
What hormones do the reproductive organs release?
A
Oestrogen and testosterone
19
Q
What effect on the body do the reproductive organs have?
A
- Responsible for the development and regulation of the female reproductive system and secondary sex characteristics
- Responsible for the sex drive, sperm production, muscle strength and secondary sex characteristics
20
Q
What is the pituitary gland regulated by?
A
The hypothalamus
21
Q
What is the pituitary gland divided into?
A
- Anterior lobe
- Posterior lobe
22
Q
What is the fight or flight response?
A
A sequence of internal processes that prepares the body for struggle or escape
23
Q
What two branches is the autonomic nervous system divided into?
A
The parasympathetic branch and the sympathetic branch
24
Q
What is the sympathetic branch responsible for?
A
The SAM respose to stress- physical arousal of the body
25
What is the parasympathetic branch responsible for?
Counteracting the SAM response to stress- relaxation and energy conservation
26
Are the sympathetic and parasympathetic branches fast or slow acting?
Sympathetic is fast and parasympathetic is slow
27
What physiological changes are occurring when the sympathetic branch is activated?
- Dilates pupils
- Inhibit salivation
- Accelerates heartbeat
- Dilate bronchi
- Inhibits digestion
- Stimulates glucose release
- Relaxes bladder
28
What physiological changes are occurring when the parasympathetic branch is activated?
- Constricts pupils
- Stimuates salivation
- Slows heartbeat
- Constrict bronchi
- Stimulates digestion
- Contracts bladder
29
What are the body's two stress responses responsible for?
- Acute stress (short term)
| - Chronic stress (long term)
30
What is responsible for the acute stress reponse?
Sympathetic Adrenal Medullary Axis (SAM)
31
What is responsible for the chronic stress reponse?
Hypothalamic Pituitary Adrenal Axis (HPA)
32
Outline the SAM response to acute stress e.g. falling down
- Activates the sympathetic branch of the ANS
- Neuronal messages are sent to the inner core of the adrenal gland called the adrenal medulla
- This results in the secretion of adrenaline and noradrenaline
- This leads to the fight or flight reponse and the physiological changes
33
Outline the HPA reponse to chronic stress e.g. multiple deadlines
- Releases Corticotrophin Releasing Hormone
- Activates the pituitary gland
- Causes the release of the ACTH stress hormone
- This stimulates the outer edge of the adrenal gland called the adrenal cortex
- Allows the production of glucocortoids (Glucose and Cortisol)
- Glucocortoids are released into the liver to release stored glucose
- Leads to the suppression of the immune system
34
Evaluate the fight/flight response
- Taylor et al found that females respond to stress differently- tend (protecting their young) and befriend (protecting alliances with other women) as fleeing too readily can endanger their offspring
- Response to chronic stress can be counterproductive in today's society- in modern life the stress response can be repeatedly activated which can lead to physical damage in blood vessels and eventually heart disease
- The freeze reponse challenges fight or flight- Gray argues that before fighting or fleeing most animals freeze to stop, look and listen in order to make the best response
35
What are neurons?
Cells that are specialised to carry neural information throughout the body
36
What are the three types of neuron?
- Sensory
- Motor
- Relay
37
What is the general structure of a neuron?
1. Cell body- control centre of the neuron
2. Dendrites- receive signals from other neurons or from sensory receptors
3. Axon- carries the electrical impulse away from the cell body down the length of the neuron
4. Myelin sheath- insulates/ protects the axon and allows the nerve impulse to be transmitted more rapidly along the axon
5. Terminal buttons- these are at the end of the axon and communicate with the next neuron across the synapse
38
What are sensory neurons?
- Carry nerve impulses from sensory receptors to the spinal cord and brain
- Convert information from senses into neural impulses
- When these impulses reach the brain they are translated into sensations
- Some neurons terminate in spinal cord to allow reflex actions
- They have long dendrites and short axons
39
What are relay neurons?
- Most neurons lie somewhere between the sensory input and motor output
- Allow sensory and motor neurons to communicate with each other
- Relay neurons lie wholly within the spinal cord and brain
- They have short dendrites and short axons
40
What are motor neurons?
- These neurons connext the central nervous system to muscles
- They form synapses with muscles and control their contraction
- When stimulated, motor neurons release neurotransmitters that bind to the muscle receptors to trigger a response
- This leads to muscle movement
- They have short dendrites and long axons
41
What is synaptic transmission?
When a nerve impulse passes across the synaptic cleft from one neuron to another
42
Outline the process of synaptic transmission
- Electrical impulse arrives at the pre-synaptic terminal
- This stimulates vesicles (sacs holding neurotransmitters)
- This releases neurotransmitters which diffuse across the gap between the two neurons, known as a synapse
- The neurotransmitters arrive at te postsynaptic receptors
- Postsynaptic effects are either excitatory or inhibitory
43
What are excitatory neurotransmitters?
- Neurotransmitters such as adrenaline are the system's on switches
- These cause excitation of the post-synaptic neuron by increasing its positive charge
- This makes it more likely to fire
44
What are inhibitory neurotransmitters?
- Neurotransmitters such as serotonin are the system's off switches
- These cause inhibition of the post-synaptic neuron by increasing its negative charge
- This makes it less likely to fire
- Inhibitory neurotransmitters are responsible for calming the mind and body
45
What is the likelihood of a cell firing determined by?
- Adding up the excitatory and inhibitory neurotransmitters binding to the post-synaptic neuron
- The net result of this calculation (summation) determines whether or not the cell fires
46
What is the localisation of cortical function?
The theory that specific areas of the brain are associated with different functions
47
What functions are associated with the brain stem?
Basic life functions such as breathing and heart rate
48
What functions are associated with the cerebellum?
Basic motor control, balance and some simple learning
49
What functions are associated with the cerebrum?
Higher functions such as emotion, complex perception and thinking
50
What is the location and function of Broca's area?
Location: Frontal lobe
Function: Speech production
51
What is the location and function of the motor cortex?
Location: Frontal lobe
Function: Coordinates voluntary movement
52
What is the location and function of the somatosensory area?
Location: Parietal love
Function: Interprets sensory input
53
What is the location and function of the visual cortex?
Location: Occipital
Function: Interprets visual information
54
What is the location and function of Wernicke's area?
Location: Temporal
Function: Speech comprehension
55
What is the location and function of the auditory centre?
Location: Temporal
Function: Interprets auditory information
56
What does damage to Broca's area result in?
Broca's aphasia- which is characterised by slow and laborious speech. Patients may have difficulty finding words and naming certain objects.
57
What does damage to Wernicke's area result in?
Wernicke's aphasia- patients produce nonsense words in speech
58
Evaluate localisation of function
CASE STUDIES PROVIDE SUPPORT: E.g. Phineas Gage, stroke victims with damage to Broca's or Wernicke's area
SUPPORT FROM BRAIN SCANS: e.g. Peterson et al was able to show activity in Wernicke's area during a listening talk and Broca's area during a reading task
ALTERNATIVE THEORY, EQUIPOTENTIALITY: suggests other parts of the brain are equally well-equipped to carry out specific cognitive functions following injury e.g. Lashley's rats (removed between 10% and 50% of the cortex in rats learning a maze and found no single area was more important than any other in terms of the rats learning the maze)
NEURONAL PLASTICITY IS A CHALLENGE: when one part of the brain is damaged and a function is lost the rest of the brain is able to reorganise itself to help to recover the function. Often seen in stroke victims.
59
What is lateralisation?
The idea that the two halves of the brain are functionally different and that each hemisphere has functional specialisations
60
What connects the two hemispheres?
The corpus callosum which is made of nerve fibres
61
What did Sperry and Gazzaniga aim to do?
To investigate the capabilities of split brain patients
62
Outline Sperry and Gazzaniga's procedure
- An image/word was projected to the patient's left visual field or the right visual field
- Many different talks were conducted
- In the describe what you see task the participant had to describe what they saw
- In the tactile task an object was placed in the patient's hand and they had to describe what they felt
- In the drawing task the participants had to draw what they saw
63
What did Sperry and Gazzaniga find?
- The left hemisphere is responsible for speech and language
- The right hemisphere specialises in visual and spacial processing and facial recognition
- This suggests that the connectivity betweent the different regions is as important as the operation of the different parts
64
What did Sperry and Gazzaniga conclude?
There are a number of key differences between the two hemispheres
65
Evaluate Sperry and the lateralisation theory
STRENGTH: increases neural processing capacity- when one hemisphere is carrying out one function the other is free to carry out another. For example, Rogers et al found that domestic chickens can find food and be vigilant for predators simultaneously so lateralisation has an evolutionary advantage
WEAKNESS: lateralisation changes with age. For exampe, Szalfarski et al found that language becomes more lateralised in the left hemisphere with increasing age in young people but after the age of 25 it decreases with each decade of life. Lateralisation cannot be generalised because age is an extraneous variable
WEAKNESS: Contradictory evidence has been found from more recent studies- evidence from case studies have shown that the brain can adapt and change. For example, J.W. developed the capability to speak out of the right hemisphere of the brain, meaning that he could speak about information presented to the left or right side of the brain
66
State the 4 ways of studying the brain
- EEG
- ERP
- Post mortem
- fMRI
67
What is EEG?
- Stands for electroencephalography
- Measures electrical activity
- The reading that is produced is of the brainwave activity occurring at that time
- E.g. alpha, beta, delta and theta
68
What are the advantages of EEG?
- Provides a recording in real time so can accurately measure a particular task or activity
- Useful in clinical diagnosis e.g. diagnosing whether someone experiencing seizures has epilepsy
69
What are the disadvantages of EEG?
- Cannot reveal what is going on in the deeper regions of the brain such as the hypothalamus as it is not ethically permissable to implant electrodes in humans
- Several electrodes can pick up electrical activity so it is not useful for pinpointing the exact source
70
What is ERP?
- Stands for event-related potential
- Electrical responses shown within an EEG
- The brain's response to a stimulus
- The stimulus is presented many times in order to rule out extraneous factors
- ERPs within looms are sensory and later ERPs are cognitive
71
What are the advantages of ERP?
- Provide a continuous measure so it makes it possible to determine how processing is affected by a specific stimulus
- Can measure the processing of stimuli even in the absence of a behavioural response- possible to monitor 'covertly'
72
What are the disadvantages of ERP?
- ERPs are small and difficult to pick out from other electrical activity so require a large number of trials to gain meaningful data
- Only sufficiently strong voltage changes are recordable- the generation of ERPs tends to be restricted to the neocortex
73
What is a post-mortem?
It involves looking at a body after death and is carried out by pathologists
74
What are the advantages of a post-mortem?
- Allows for a more detailed examination of anatomical and neurochemical aspects e.g. enables to reach deeper regions
- Harrison (2000) claims that post-mortem studies have played a central part in our understanding of the origins of schizophrenia
75
What are the disadvantages of a post-mortem?
- Factors can influence post-mortem brains e.g. variety of death cirumstances, post-mortem delay, varying stages of disease, drug treatments, age of death etc
- Retrosepctive as the person is already dead- unable to follow up on anything
76
What is fMRI?
- Stands for functional magnetic resonance imaging
- Measures brain activity
- Measures blood flow to and from specific areas of the brain
- Oxygenated blood has a different level of magnetism to deoxygenated
- Active areas recieve oxygenated blood
- Uses magnetic waves to measure brain activity
77
What are the advantages of fMRI?
- Non invasive and doesn't expose the brain to potentially harmful radiation
- More objective and reliable than verbal reports. Useful to investigate things that people are incapable of providing in verbal reports
78
What are the disadvantages of fMRI?
- It measures changes in blood flow so it is not a direct measure of neural activity in particular brain areas- not truly quantitative
- Overlooks the networked nature of the brain activity- it only focuses on localised activity. Critics claim communication is most critical to mental function
79
What is brain plasticity?
Brain plasticity is the idea that the brain has an ability to change and adapt as a result of experience. Recent research has shown that the brain continues to create new neural pathways and alter existing ones to adapt to new experiences outside of childhood
80
Name and explain two examples of brain plasticity
Video games- Kuhn et al compared a control group with a video game training group that trained for 2 months and found a significant increase in grey matter in various brain areas (cortex, hippocampus and cerebellum). This was not evident in the control group which shows the training resulted in new synaptic connections
Meditation- Davidson et al found that Tibetan monks had much greater activation of gamma waves whereas students only showed a slight increase which shows that meditation changes the workings of the brain in short term and produces permanent changes
81
What is functional recovery?
Functional recovery refers to the brain moving functions from a damaged area of the brain after trauma to other undamaged areas
82
What is neuronal unmasking?
Wall identified dormant synapses in the brain which are synaptic connections which exist anatomically but their function is blocked. When a surrounding area of the brain becomes damaged there is an increase in input to these synapses which opens these synapses and opens connections to regions of the brain not normally activated
83
What is the effect of stem cells in functional recovery?
Stem cells are unspecialised cells. If they are implanted directly into the brain they could replace dead or dying cells. Or, they could secrete growth factors which rescue injured cells. Also, transplanted cells can form a neural network which links uninjured brain sites where stem cells are made to damaged regions of the brain
84
Evaluate plasticity/ functional recovery
Plasticity:
Research support from animal studies- Kempermann et al found that rats in an enriched environment had more neuronal connections compared to rats in laboratory cages
Research support from human studies- Maguire found that London taxi drivers had a significantly larger posterior hippocampus compared to a control
Functional recovery
Individual differences- research suggests that age might influence speed of recovery and education may be a mediating factor. This means we might need to take a more holistic approach
Research support from animal studies- Tajiri implanted stem cells into one group of brain damaged rats and then left the control group with no stem cells. After 3 months the rats with the stem cell treatment showed clear development of neuron like cells in the area of injury which was not the case for the other rats
85
What are biological rhythms?
Cyclical variations that occur naturally within our bodies as a result of certain structures and chemical changes
86
What are the three main rhythms?
Circadian
Ultradian
Infradian
87
How long does a circadian rhythm last?
Approximately 24 hours
88
How long does an ultradian rhythm last?
Less than 24 hours
89
How long does an infradian rhythm last?
More than 24 hours
90
What are endogenous pacemakers?
Internal structures or chemicals that can regular our biological rhythms e.g. melatonin, our heart, our SCN
91
What are exogenous zeitgebers?
External factors that regulate biological rhythms e.g. social cues, sunlight
92
What is the SCN?
The suprachiasmic nucleus is the master circadian pacemaker in mammals
93
What is the role of melatonin?
- Melatonin is a hormone that regulates sleepiness and wakefulness
- Light from the SCN reduces melatonin production
- Darkness increases melatonin production, also triggered by the SCN
- Melatonin could be thought of as the hormone of darkness
94
Describe the role of core body temperature
- it also follows a circadian rhythm
- lowest at 4:30 am
- highest at 6pm
- most people experience a small drop in temperature between 2pm and 4pm making us feel sleepy
95
Describe the role of hormone production
- some hormones also show a circadian rhythm
- melatonin peak in the evening and troughs in the morning
- this causes us to feel sleepy or awake
- cortisol also follows a circadian rhythm
96
What did Michel Siffre aim to do?
To investigate circadian rhythms in the absence of exogenous zeitgebers
97
Outline Siffre's procedure
- He spent long periods of time underground (6 months)
- He had no external cues e.g. no daylight, clocks etc
- He woke, slept and ate when he felt it was appropriate to do so
98
What did Siffre find?
- His sleep-wake cycle was erratic at first
- On his second occasion his circadian rhythm settled to just over 24 hours
- On his final stay he found that his body clock ticked more slowly, stretching his circadian rhythm to 48 hours
99
What did Siffre conclude?
- Exogenous zeitgebers have a role in our circadian rhythms
| - We also have a strong natural internal biological rhythm
100
Evaluate research into circadian rhythms
WEAKNESS: Methodology- Research such as Siffre and Folkard presumes that sunlight is the main exogenous zeitgeber and artificial/ dim light has no effect. However research by Czeisler has shown that circadian rhytms can be entrained by both
WEAKNESS: Individual differences- Czeisler found that individual cycles can vary between 13 to 65 hours so we may be overly reductionist in applying one rule to all and we may need to take a more holistic approach
STRENGTH- Real life applications- Chronotherapeutics uses the principles of biological rhythms to identify optimum timings for administering medications. For example, cancer drugs have been found to be 50% more effective when given at a particular time
WEAKNESS- A lot of research into circadian rhythms uses case studies which are difficult to generalise as they lack population validity
101
Outline support for the role of the SCN
- Morgan bred a strain of hamsters so they had circadian rhythms of 20 hours
- SCN neurones from these abnormal hamsters were transplanted into the brains of abnormal hamsters
- The normal hamsters displayed the same abnormal circadian rhythms of 20 hours
- The transplanted SCN had imposed its pattern on the recipient's brain
- This has been further supported by a reverse experiment where SCN neurones from normal hamsters were planted into abnormal hamsters and this changed their circadian rhythms to 24 hours
102
Outline Folkard's research into circadian rhythms
- 12 participants lived in temporal isolation for 3 weeks
- This meant they were isolated from natural light and other time cues
- They agreed to go to bed at 11:45pm and get up at 7:45pm
- The clock initially ran to time but gradually quickened until it indicated a passing of 24 hours for 22 hours
- All but one participant continued to have a 24 hour cycle which shows that exogenous zeitgebers only have a limited effect
103
What does BRAC stand for?
Basic rest activity cycle
104
What is detected by EEG, EOG and EMG?
EEG- Brain waves
EOG- Eye movements
EMG- Muscle tension
105
What is detected by EEG, EOG and EMG in stage 1 of sleep?
EEG- Alpha and beta waves
EOG- Some tension
EMG- some tension
106
What is detected by EEG, EOG and EMG in stage 2 of sleep?
EEG- Alpha and beta waves
EOG- Slow rolling eye movements
EMG- some tension
107
What is detected by EEG, EOG and EMG in stage 3 of sleep?
EEG- Theta and delta waves
EOG- Still
EMG- Relaxed
108
What is detected by EEG, EOG and EMG in stage 4 of sleep?
EEG- Theta and delta waves
EOG- Still
EMG- Relaxed
109
What is detected by EEG, EOG and EMG in REM sleep?
EEG- Mixed brain activity
EOG- Rapid eye movements
EMG- Virtual body paralysis
110
What kind of biological rhythm is the sleep cycle and why?
An ultradian rhythm because it lasts for less than 24 hours. Each sleep cycle actually lasts for around 90 minutes
111
What is stage 1 and 2 of sleep known as?
Light sleep
112
What is stage 3 and 4 of sleep known as?
Slow wave sleep
113
What is REM?
- A separate stage of sleep (rapid eye movements)
- Usually occurs around 5 times a night for 5-15 minutes
- This is when dreaming occurs
- It is called paradoxical sleep because of the brain activity despite being asleep
114
Give three examples of research into ultradian rhythms
1. Dement and Kleitman- the first to study sleep stages objectively. Identified REM as our dream sleep
2. Ericsson indentified 90 minute performance cycles in various top performers/ experts. He found that violinists, chess players and top athletes all noted a preference for practising over a 90 min cycle which is evidence for daytime BRAC.
3. Friedman and Fisher found evidence for 90 min cycles in psychatric patients. This included eating, drinking, rest and activity which is further evidence ofr BRAC
115
What is an infradian rhythm?
A biological rhythm that lasts longer than 24 hours anc can be weekly, monthly or annually
116
What are the two main examples of infradian rhythms?
- Menstrual cycle
| - Seasonal affective disorder
117
What is the menstrual cycle?
- It occurs roughly halway through the cycle when the oestrogen levels are highest
- It is regulated by the hormones oestrogen, progesterone, FSH and LH
- After ovulation progesterone levels increase ready for possible embryoimplantation
- A typical cycle is approximately 28 days however there is a considerable variation (23 days to 36 days)
- FSH promps the egg to be released from the follicle
118
Outline McClintock and Stern's research into external control of menstrual cycles
- They followed 29 women who had had history of irregular menstrual cycles
- Sweat samples from the armpits of 9 of the women were collected, sterilised and dabbed onto the upper lip of the other twenty
- On 68% of occasions the recipients of the sweat donation had responded to the pheromones
119
What is the evolutionary advantage of external control of the menstrual cycle?
-Bentley found that synchronisation between women living in close proximity would ensure that the women would concieve and give birth around the same time and this would be beneficial because they can share breast feeding
120
What is SAD?
- Seasonal affective disorder
- At night low light levels stimulate the production of melatonin which triggers sleepiness
- The lower light levels in winter have a similar effect
- Linked to increase in depressive symptoms
- Mechanism is unknown but possibly related to serotonin regulation
121
Outline research evidence for SAD
- Terman et al researched 124 participants with SAD
- 85 were given 30 minute sunlight exposure to bright light, some in the morning and some in the evening
- Another 39 were exposed to negative ions
- It was found that 60% of the morning bright light group showed significant improvement compared to only 30% of those getting light in the evening
- Only 5% of the placebo group showed improvement
- The conclusion was that bright light administered in this way may be acting as a zeitgeber and resetting the body clock
