Biopsychology Flashcards
1
Q
What are the two main division of the nervous system?
A
Peripheral nervous system and the Central nervous system
2
Q
What are the two functions of the nervous system?
A
- To collect, process and respond to information in the environment
- To coordinate the workings of different organs and cells in the body
3
Q
What is the central nervous system made up of?
A
Brain and the spinal cord
4
Q
What is the peripheral nervous system?
A
Messages in the PNS are transferred from the
CNS to the rest of the body and from the body
back to the CNS via neurones
5
Q
What are the two divisions of the PNS?
A
Somatic nervous system and the Automatic nervous system
6
Q
What is the somatic nervous system?
A
- voluntary movement of skeletal muscles
- sensory neurons relay messages from our sensory receptors (eye receptors, touch, taste buds) to our brain
- motor neurons which carry
commands to our skeletal muscles from the brain throughout the body, allowing us to consciously move.
7
Q
What is the automatic nervous system?
A
- regulates involuntary actions and is largely done
unconsciously. - e.g. breathing, digestion
and heartbeat. - there are no sensory neurons, only motor neurons
8
Q
Comparison of SNS and ANS
A
SNS= voluntary, skeletal, motor and sensory, control centre is motor cortex
ANS= non-voluntary, smooth, motor, control centre is spinal cord
9
Q
What are the two divisions of the automatic nervous system?
A
sympathetic and parasympathetic systems
10
Q
What does the sympathetic division do?
A
stimulating effects by sending stimulating neurotransmitters to parts of the body. fight or flight
11
Q
What does the parasympathetic division do?
A
inhibiting effects by sending inhibiting neurotransmitters to parts of the body. rest or digest
12
Q
What is the endocrine system?
A
a network of glands that secrete hormones into the bloodstream
13
Q
Hormone secreted and function of the adrenal gland?
A
Hormone secreted: adrenaline
Function: deal with stress, fight or flight, force of skeletal muscle contraction
14
Q
Hormone secreted and function of testes gland?
A
Hormone secreted: testosterone
Function: plays a role in reproduction, growth and maintenance of a healthy body
15
Q
Hormone secreted and function of pineal gland?
A
Hormone secreted: melatonin
Function: initiates sleep when it gets dark
16
Q
What is the pituitary gland?
A
- the ‘master gland’ as it controls the release of hormones from all other glands by secreting a stimulating hormone (when triggered by the hypothalamus).
- the pituitary gland is located at the base of the brain which
connects the fast acting-nervous system to the slower-acting endocrine system
17
Q
Outline the flight or fight response
A
- A person enters a stressful/dangerous situation
- The hypothalamus activates the pituitary gland which triggers the sympathetic branch of the autonomic nervous system.
- ANS changes from parasympathetic state to sympathetic state.
- The adrenal medualla secretes the adrenaline into the bloodstream
- Adrenaline causes a number of physiological changes to prepare the body for fight or flight
- Once threat has passed, parasympathetic branch returns body to resting state
18
Q
Examples of how the physiological changes caused by the SNS help with fight or flight
A
Increased heart beat:
More blood and oxygen to skeletal muscles for physical action.
Dilation of pupils:
Take in light better, see threat or escape easier.
Dilates bronchi in lungs:
Breath in more oxygen which goes to the brain for more effective thinking and response planning.
Diverts blood away from digestive system:
Digesting food is not essential, blood is better used in the skeletal muscles.
Diverts blood towards the brain:
Increase in blood and oxygen leads to improved cognitive functioning.
Diverts blood towards skeletal muscles:
Help prepare them for physical action.
Increased sweating:
Helps humans to climb a tree more easily (sweaty palms)
To prepare for exercise required if fighting or fleeing.
19
Q
Structure and function of the SENSORY neuron
A
- sensory neurons are found in receptors such as the eyes, ears, tongue and skin
- carry messages from the PNS to CNS.
20
Q
Structure and function of the RELAY neuron
A
- found in the brain and spinal cord (CNS)
- they can connect to other relay neurons or between sensory
and motor neurons.
21
Q
Structure and function of the MOTOR neuron
A
- carry nerve impulses from CNS to effectors
22
Q
What is a cell body?
A
Includes a nucleus which contains genetic material of the cell. This is the control
centre of the neuron.
23
Q
What are dendrites?
A
Branch like structures which protrude from the cell body, they carry nerve impulses
from neighbouring neurons or sensory receptors towards the cell body.
24
Q
What is an axon?
A
This carries the impulse away from the cell body down the length of the neuron.
25
What is a myelin sheath?
Fatty layer that protects the axon and speeds up synaptic transmission.
26
What is a node of ranvier?
Gaps in the myelin sheath that speed up transmission of the impulse by forcing it to
jump across the gaps along the axon.
27
What is an axon terminal?
At the end of the axon, these communicate with the next neuron in the chain.
28
What is a synapse?
A gap between the pre- and post-synaptic neuron.
29
Length of dendrites and axons on motor neurons?
Dendrites: short
Axons: long
30
Length of dendrites and axons on relay neurons?
Dendrites: short
Axons: short
31
Length of dendrites and axons on sensory neurons?
Dendrites: long
Axons: short
32
Useful memory tool to remember neurons?
Motor - long like a motorway
Sensory - long fingers (dendrites)
Relay - 100m sprint - short short
33
What is the process of synaptic transmission?
1. Action potential arrives at the terminal button at the end of the neuron and it triggers the release of neurotransmitters from synaptic vesicles in the pre-synaptic neuron. These are chemical messengers that assist in the transfer of the impulse through a process called exocytosis.
2. Neurotransmitters diffuse across the synaptic gap and bind to specialised receptor sites on the postsynaptic cell dendrites. These receptor sites only recognise and are activated by particular neurotransmitters.
3. Is is the binding of the neurotransmitter to the receptor on the PSN that causes the chemical message to be converted back into an electrical impulse where signal is passed on to this neuron.
34
What are excitatory neurotransmitters?
More excitatory neurotransmitters (e.g. noradrenaline) = increase positive charge (depolarisation) = excitatory postsynaptic potential = more likely to fire
35
What are inhibitory neurotransmitters?
More inhibitory neurotransmitters (e.g. serotonin) = increase negative charge (hyperpolarisation) = inhibitory postsynaptic potential = less likely to fire
36
What is summation?
Adding up the excitatory PSP and inhibitory PSP.
37
What is localisation of function?
different parts of the brain perform different tasks and are involved in different parts of the body
38
What is the holistic theory?
all parts of the brain were involved in the processing of thought and action
39
What is the motor area?
- Located: front of head (frontal lobe)
- Voluntary movement in opposite side of body
- Damage is loss of control over fine movements on opposite side
40
What is the somatosensory area?
- Located: top of head (parietal lobe)
- Detects sensory information from the skin, e.g. touch, heat, pressure
- Size of sensory area denotes body part’s sensitivity – larger areas feel more sensitive
- Damage – reduced ability on the opposite side of the body in the detection of light touch and some difficulty identifying objects by touch.
41
What is the Visual Area?
- Located: back of head (occipital lobe)
- Processes visual stimuli entering from the opposite visual field
- Specialised regions that process things such as colour, spatial information, depth
texture and motion.
- Damage – loss of specific aspects of vision. damage to left visual area may cause blindness in right visual field.
42
What is the auditory area?
- Located: bottom of head (temporal lobe)
- Involved with detecting the volume and pitch of sound.
- Damage – Hearing loss, inability to understand speech
43
What is Broca's area?
- Located: Left frontal lobe
- Speech production
- Damage – Broca’s aphasia - slow, laborious speech and lacking in fluency.
- Patient 'Tan'
44
What is Wernicke’s area?
- Located: Left temporal lobe
- Speech comprehension
- Damage – Wernicke’s aphasia
- produce nonsense words
45
What are the strengths of localisation of function?
- damage to areas has been linked to mental disorders - OCD
- evidence from brain scans
46
What are the weaknesses of localisation of function?
- language may not be localised to broca and wernicke's areas
47
What is hemispheric lateralisation?
the theory that certain functions are controlled by one side of the brain and not the other
48
How does hemispheric lateralisation work?
- left hemisphere controls right side of the body
- right hemisphere controls left side of the body
49
What does the left hemisphere do?
speech, writing = analyser
50
What does the right hemisphere do?
creativity, artistic = synthesiser
51
What does the corpus callosum do?
bundle of nerves fibres that connects left and right hemisphere of brain. in split brain patients this is cut!
52
How do the visual fields work?
- left visual field goes to right hemisphere
- right visual field goes to left hemisphere
53
What happened in Sperry's 'describe what you see' experiment?
picture presented to either left or right visual field.
rvf = Lh = say what they saw cos left side has the lang centres
lvf = Rh = say saw nothing
54
What happened in Sperry's 'drawing' experiment?
(same as before but drawing)
rvf = Lh = can't draw
lvf = Rh = can draw
55
What are the strengths of hemispheric lateralisation?
- even in connected brains the hemispheres process info differently
- more split-brain research
56
What are the weaknesses of hemispheric lateralisation?
idea of LH as analyser and RH as synthesiser may be wrong
57
What is brain plasticity?
brain's ability to change and adapt, both functionally and physically throughout life. it's not fixed and static. brain can make new neural pathways.
58
What does the brain look like in infancy?
brain experiences rapid growth in synaptic connections peaking at 15,000 at age 2-3 where the connections are approximately twice as many as an adult's brain.
59
What is synaptic pruning?
rarely used connections are deleted and frequently used connections are strengthened
60
What is grey matter?
all the connections between neurons
61
What is white matter?
consists of axons connecting different parts of grey matter to each other.
62
What is the key research supporting brain plasticity?
Maguire et al. (2000)
Navigation-related structural change in the hippocampi of taxi drivers.
63
Method to the Maguire study?
structural MRI scans of 16 right-handed male London taxi drivers compared to 50 healthy right-handed males who did not drive taxis
64
Results to the Maguire study?
1. Increased grey matter was found in the brains of taxi drivers
2. Changes with navigation experience – A correlation was found between the amount of time spent as a taxi driver and volume in the right posterior hippocampus.
65
What are the strengths of brain plasticity?
life-long ability - novice golfers
66
What are the weaknesses of brain plasticity?
negative behavioural consequences
67
What is functional recovery?
where the brain recovers abilities previously lost due to brain injury. brain functions move from damaged area to undamaged area
68
What happens after brain trauma?
There is a degree of spontaneous recovery which happens very quickly. However, this slows down after several weeks or months and rehabilitative therapy is usually require to further recovery, such as electrical stimulation of the brain.
69
What is denervation supersensitivity?
- This occurs when axons that do a similar job become aroused to a higher level to compensate for the ones that are lost.
- However it can have negative consequences of oversensitivity to some messages such as pain
70
What is axonal
sprouting?
the growth of new nerve endings which connect with other undamaged nerve cells to form new neural pathways
71
What is Recruitment of homologous (similar) areas?
Similar areas on the opposite side of the brain to perform specific tasks.
E.g. if Broca’s area was damaged on the left hemisphere, then the right sided equivalent could carry out its functions.
72
What is the research support for functional recovery of the brain after trauma?
Danelli et al (2013) - The case study of EB
73
What was the trauma to the brain for EB?
Virtually all of the left hemisphere was removed
74
How did that initially affect EB?
Lost all linguistic abilities
75
What were the finding at age 5 and age 17 for EB?
5 = went to an intensive rehabilitation programme + language abilities started to improve
17 = functioning linguistically well
76
How does Danelli's study support recovery after brain trauma?
shows that if one side is damaged the other side can take over
77
What are the strengths of functional recovery?
real world application - stroke therapy
78
What are the weaknesses of functional recovery?
level of education may influence recovery rates
79
How do post-mortems work?
1. behaviour - study individual's behaviour whilst they're still alive
2. brain - study their brain after death, compared to normal brain
3. correlation - between abnormal behaviour of patient and a particular area of the brain
80
What are the strengths of post-mortems?
detail - study beyond cerebral cortex e.g. hippocampus
81
What are the weaknesses of post-mortems?
- no cause and effect
- no informed consent
82
How do fMRIs work?
1. blood flow = measures blood flow whilst a person performs a task
2. oxygen = if brain area is more active, requires more oxygen
3. magnetic = oxygen released making haem deoxygenated, different magnetic quality to oxygenated haem
83
What are the strengths of fMRIs?
- high spatial resolution
- no radiation
84
What are the weaknesses of fMRIs?
low temporal resolution
85
How do EEGs work?
1. electrodes = measures electrical activity of brain cells + neurons through electrodes attached to scalp
2. waves = electrical signals plotted on graph as waves
86
How do EEGs and ERPs differ?
EEG gives general reading of brain's activity, but this is brain's response to specific response
87
How do ERPs work?
measure very small voltage changes that are triggered by specific events
88
What are the strengths of EEGs and ERPs?
- eeg can diagnose brain disorders e.g. epilepsy
- both cheaper than fMRI
- both have high temporal resolution
89
What are the weaknesses of EEGs and ERPs?
both have low spatial resolution
90
What is temporal resolution?
how quickly the brain scan can detect changes in brain activity
91
What is spatial resolution?
how accurately it can show exactly which area of brain is active
92
What is a circadian rhythm?
takes 24 hours for a cycle!
e.g. S/W cycle
93
What is an endogenous pacemaker?
body's internal biological clock
94
How does the endogenous pacemaker work in S/W cycle?
suprachiasmatic nucleus is above optic chiasm, provides info from eye about light, regulates pineal gland with melatonin
95
What is an exogenous zeitgeber?
external changes in the environment
96
How does the exogenous zeitgebers work in S/W cycle?
light which influences SCN
97
What is research into investigating if the sleep/wake cycle is free-running?
Siffre - six months alone in a cave
98
What was the aim of Siffre's study?
To see what his 'natural' sleep-wake cycle was when deprived of external environmental cues.
99
What were the results of Siffre's study?
- the effects of dark and loneliness were severe- he was depressed due to his lack of freedom, became desperate for companionship, began to think about suicide.
- found we have an internal biological clock
- S/W cycle is closer to 25 hours
- shows the need for exogenous zeitgebers
100
What are the strengths of cirdadian rhythms?
- shift workers
- used to improve medical treatments
101
What are the weaknesses of cirdadian rhythms?
generalisations difficult to make
102
What is a infradian rhythm?
takes longer than 24 hours e.g. menstrual cycle
103
How long is the menstrual cycle?
time from first day of period to day before her next period. average length is 28 days
104
What happens in the menstrual cycle?
first half = oestrogen rises which causes ovary to develop and release an egg, lining of womb thickens
second half = progesterone rises which helps maintain lining of womb in prep for embryo
105
What is research into the menstrual cycle?
Synchronisation study: McClintock & Stern
106
What is the aim of the menstrual cycle study?
To show that the menstrual cycles between women may synchronise by pheromonal secretions from other women.
107
What is the sample of the menstrual cycle study?
20 females (20-35) with a history of irregular periods plus a control group of 9 other females who were at different stages of their menstrual cycle.
108
What is the method of the menstrual cycle study?
The control group of women wore a cotton pad in their armpits for at least 8 hours. The pads were then treated with alcohol and frozen. The pads were then rubbed on the upper lip of the 20 students so that the pheromones could be inhaled.
109
What were the findings of the menstrual cycle study?
On 68% of occasions the recipients of the sweat donation had responded to the pheromones, so exogenous zeitgebers could be pheromones
110
What are the strengths of infradian rhythms?
may be explained by natural selection
111
What are the weaknesses of infradian rhythms?
methodological shortcomings
112
What is an ultradian rhythms?
take less than 24 hours e.g. stages of sleep
113
What happens in stages 1 and 2 of sleep?
- light sleep where easily woken
- stage 1 = brain waves are high frequency and have short amplitude. alpha waves
- stage 2 = still alpha waves but random pattern changes called sleep spindles
114
What happens in stages 3 and 4?
- deep sleep where hard to wake
- lower frequency and higher amplitude
- delta waves
115
What happens in stage 5?
- body is paralysed, theta waves
- eyes occasionally move around, dreams
116
What are the strengths of ultradian rhythms?
- improved understanding of age-related changes in sleep
117
What are the weaknesses of ultradian rhythms?
- significant variation between people
