Biopsychology - Brain scanning and bio rythms left too do Flashcards
1
Q
What are the key facts about the nervous system?
A
- Is made up of billions of neurons
- The brain recieved sensory inputs from the bodys receptors mainly via the spinal cord
- The brain is connected to the muscles of the skeleton and controls internal organs
- It collects, proceses and responds to information from the enviroment
2
Q
What are all the parts of the nervous systems?
A
- Central nervous systems
- Peripheral nervous system
- Autonomic nervous system
- Somatic nervous systems
- Parasympathetic division
- Sympathetic division
3
Q
What is included in the central nervous system?
A
Brain and spinal cord
4
Q
Whats included in the peripheral nervous system?
A
Cranial nerves and spinal nerves
5
Q
Whats included in the autonomic nervous system?
A
Heart muscle, smooth muscle, glands
6
Q
Whats included in the somatic nervous system?
A
Voluntary skeletal muscles
7
Q
What does the parasympathetic division do?
A
- ‘Rest and digest’
- Slows the body down and reverses the effects of the sympathatic branch
8
Q
What does the sympathetic division do?
A
- ‘Active and alert’
- Prepares the body for the survival response ‘fight or flight’
- Active during sports
9
Q
How many major divisions in the nervous systems are there?
A
2
10
Q
What are the 2 major divisions of the nervous systems?
A
- Central nervous system
- Periphral nervous system
11
Q
What is the spinal cord responsible for?
A
Reflex actions such as movements and the reflex arc
12
Q
What is the brain the centre of?
A
Conscious awareness
13
Q
What are the 3 main parts of the brain?
A
- Cerebellum
- Cerebral cortex/cerebrum
- Brain stem, medulla
14
Q
What is the outer layer of the cerebrum?
A
Cerebral cortex
15
Q
How many lobes does the cerebral cortex have?
A
4
16
Q
What are the 4 lobes of the cerebral cortex?
A
- Frontal lobe
- Parietal lobe
- Temporal lobe
- Occipital lobe
17
Q
What is the function of the frontal lobe?
A
Motor movements, personality and deciision maker, Brocas area (production of speech)
18
Q
What is the function of the temporal lobe?
A
- Proccessing auditory information
- Wernickes area (understanding language)
19
Q
What is the function of the occipital lobe?
A
Proccessing visual information
20
Q
What is the function of the parietal lobe?
A
Processes sensory information
21
Q
Where are the 4 cortex’s in the brain?
A
- Motor cortex - frontal lobe
- Auditory cortex - temporal lobe
- Visual cortex - occipital lobe
- Somatosensory cortex - parietal lobe
22
Q
What does the peripheral nervous system connect to?
A
Connects central nervous system to the rest of the body
23
Q
What are the two parts of the peripheral nervous system?
A
- Somatic nervous system
- Autonomic nervous system
24
Q
What is the key information about the somatic nervous system?
A
- Controls voluntary movement in the skeletal muscles
- Contains sensory neurons and motor neurons
- Sensory neurons transmit signals from the body to the brain
- Motor neurons transmit signals from the brain to the body
25
What is the key information about the autonomic nervous system?
- Regulates involuntary functions
- Recieves signals from sensory neurones to create involuntary responses in caradic and smooth muscles to regulate function such as heart rate and digestion
26
What are the two sub divisions of the autonomic nervous system?
- Sympathetic nervous system
- Parasympathetic nervous system
27
What is the sympathetic nervous system?
Controls our responses when we are in an emergency/threatening situation to provide rapid energy - 'fight or flight' response
28
What is the parasympathetic nervous system?
Returns our body to its normal resting state after an emergency has passed, refered to as 'rest and digest'
29
What is the structure of neurons?
- Contails a cell body (soma) which contains a nucleus (stores genetic code)
- Dendrites branch our from the cell body and carry impulses to other neurons
- Axon projects away from the cell body and carries the signals recieved by the dendrites to other neurons
- Myelin sheath - a white fatty substance which insulates the axon and speeds the rate of conduction of signals
- Terminal - where a impulse can be transmitted to another neuron
30
What are the 3 types of neurons?
- Motor
- Relay
- Sensory
31
What is the structure of a motor neuron?
Short dendrites protrude directly from the cell body which is at one terminal, impulse carried away by long axon to another terminal
32
Where are motor neurons located?
Cell body is inside the Central nervous system
Axon is inside peripheral nervous system
33
What is the function of a motor neuron?
Controls muscles and organs (effectors)
34
What is the structure of a relay neuron?
Short dendrites carry impulse to cell body, impulse carried away to very short axon
35
What is the location of relay neurons?
Entire Neuron is inside central nervous system?
36
What is the function of relay neurons?
Allows motor and sensory neurons to communicate
37
What is the structure of a sensory neuron?
A long dendrite carries impulse to the cell body whic is at the side of a short axon (cell body has no dendrites itself)
38
Where is sensory neurons located?
Cell body is outside the central nervous system
Axon is inside the peripheral nervous system
39
What is the function of sensory neurons?
Carry nerve impulses
40
Describe the knee-jerk reflex
1) receptors on the skin (sense organ) detect the tap (stimulus)
2) Sensory neuron carries impulse to central nervous system
3) Impulse transmitted to relay neuron in central nervous system where sensation is proccesses
4) Impulse carried to the peripheral nervous system
5) Impulse transmitted to motor neuron
6) Receptors on muscles (effector) contract (response) - knee moves in response
41
What is synaptic transmission?
Refers to how neurons communicate with (transmit messages to) one another
42
What happens before action potential occurs in synaptic transmission?
The activated cell changes from its negative resting state to a positive activated state
43
What happens during synaptic transmission?
1) Action potential travels down the axon
2) Impulse travels down the axon on the pre-synaptic neurons, reaches the terminal buttons which triggers the release of neurotransmitters from the vesicles
3) Neurotransmitters diffuse through the synapse and bind to receptor sites on the post synaptic neurone
4) Stimulation off post synaptic receptors by neurotransmitters results in exicitation or inhibition of the post - summation
5) Leftover neurotransmitters is reuptake, broken down by enzymes or diffuses
44
What does the neurotransmitters contents at the synapse determine?
Whether the synapse is excitatory or inhibitory
45
What happens if the neurotransmitters is excitatory in synaptic transmission?
The post synaptic neuron is instructed to 'fire' (conduct a action potential)
46
What happens if the neurotransmitter is inhibitory in synaptic transmission?
The recieving neuron is instructed not to 'fire' (not to conduct action potential)
47
What happens when a post synaptic neuron recieves both inhibitory and excitatory inputs in synaptic tranmission?
It adds them together - where it fires or not depends on which is greater, this is known as summation
48
Describe excitatory neurotransmitters
- Are 'on switches'
- Increase the likelehood that a signal is sent to the post synaptic neuron
- This is then more likely to fire as it becomes positively charged - called excitatory post synaptic potential (EPSP)
49
Name two examples of excitatory neurotransmitters?
- Dopamine
- Noradrenaline
50
Describe inhibitory neurotransmitters?
- Are 'off switches'
- Decreases the likelehood that a signal is sent to the post synaptic neuron because it becomes more negatively charged
- This is called inhibitory post synaptic potential (IPSP)
51
Name two examples of inhibitory neurotransmitters
- GABA
- Serotonin
52
What does normal brain function and activity rely on?
A careful balance between excitatory and inhibitory functions
53
What can a imbalance of excitatory and inhibitory influences cause?
Neurological and mental disorders
54
What is the endocrine system?
- Works alongside the nervous system
- Is a network of glands within the body
55
What are glands?
- Secrete various hormones into the bloodstream, which then have an effect on organs that have cells with receptors for those hormones
56
What does glands effects on the organs influence?
Processes such as growth, metabolism and reproduction
57
Describe the pituitary gland?
- Known as the 'master gland'
- Secretes hormones itself but also controls the activity of all other glands in the body
- Sits just below the hypothalamus and can be divided into anterior lobe (front) and posterior lobe (back)
58
What is the anterior lobe responsible for in the pituarity gland?
- Releasing the hormone ACTH
- This hormone stimulates the adrenal cortex to release cortisol during times of chronic stress to give us energy
59
What is the posterior lobe of the pituarity gland resposible for?
- Releasing the hormone ocytocin
- Responsible for producing contractions in the uterus during childbirth
60
What is the hormone associated with the thryoid gland?
Thyroxine
61
Where is the thyroid land located?
Front of windpipe (trachea)
62
What is the function of the thyroid gland?
Regulate metabolic rate (turns food into energy)
63
What hormone is associated with the ovaries?
Oestrogen
64
Where are the ovaries located?
Behind the pelvis, above the uterus?
65
What is the function of ovaries?
Development of sex characteristics in women (breasts, pubic hair) and regulation of the menstrual cycle and fertility
66
What is the hormone associated with testes?
Testosterone
67
Where are the testes located?
Inside the scrotum
68
What is the function of testes?
Development of male sex characteristics (lowers voice, sperm production) and regulation of aggressive behaviours
69
What is the hormone associated with the adrenal medulla gland?
Adrenaline
70
Where is the adrenal medulla located?
Kidneys
71
What is the function of the adrenal medulla?
Prepares the body for fight/flight by increasing heart rate etc
72
What is the flight or fight response?
Describes the response to acute stress - a sudden threat or emergency. This activates a serious of events in the nervous system
73
What is the process of the fight or flight response?
- Hypothalamus is stimulated and detects acute stressor
- A signal is sent down the sympathetic branch of the nervous system
- A message is sent to the adrenal medulla that releases adrenanline and noradrenaline
- Adrenanline is released that prepares body for fight or flight
- The parasympathatic nervous system restores the body back to homeostasos - rest and digest
74
What two hormones are associated with fight or flight response?
Adrenaline
Noraadrenaline
75
What are the effects of the hormones adrenaline and noradrenaline in the fight or flight response?
- Blood being diverted away from the skin and too vital organs - increasing heart rate and blood pressure
- Rapid respiration to boost oxygen supply to the brain
- Pupils dilate
76
What are the physical responses of the fight or flight response intended to do?
To help a person survive a dangerous situation by preparing you to either run away or defend yourself
77
What are the weaknessses of the fight or flight response?
- Human behaviour is not limited to just two responses
- Doesnt explain stress response in females
- Can have a negative effect on health
78
79
Why is 'human behaviour is not limited to just two responses' a criticism of the fight or flight response?
Gray suggests that the first response to danger is to avoid confrentation alothether, which is shown by a 'freeze' response
During the freeze response, humans are hypervigilant while they appraise the situaton to decide the best course of action for that particular threat
80
Why doesn't the fight or flight explanation fully explain the stress response in females?
Taylor suggests that females have evolved a 'tend and befreind' response: tending to offpsring and befreinding other females for social support
Highlights beta bias in the area of psychology as we assumed females and males respond the same so it can be limitely applied to women
HOWEVER, has prompted recent research which has provided an alternate explanation that applies to females
81
Why can the fight or flight response have a negative effect on health?
The fight or flight response may of been a useful survival mechanism for ancestors that faced life threatening situations, modern day like rarely requires such a intense response
Fight or flight response can increase blood pressure, cause damage to blood vessels and contribute to heart disease - Therefire the theory is maladaptive
82
What is the largest part of the brain
Cerebrum
83
How thick is the top layer of the cerebrum
1 cm thick
84
What is the cerebrum known as?
Cerebral cortex
85
How many hemispheres does the brain have?
2 - left and right
86
What are the two hemisphers of the brain connected by?
Fibres called the corpus callosum
87
What does the brain being contralateral mean?
Areas in the right hemisphere recieve information from and are concerned with activities in the left side of the body (and vice versa)
88
What does localisation of funtion mean?
Different areas if the brain are responsible for different behaviours or processes
89
What is localisation of function also known as?
Cortical specialisation
90
What are said to be localised to specific areas of the cortex?
Functions such as language, visual perception and movement
91
If the brain is localised then what does it mean if a certain area is damaged?
The functions in that area will be affected
92
What are the 4 cortexs?
- Motor
- Somatonsensory
- Visual
- Auditory
93
Where is the location of the motor cortex?
Located in the frontal lobe
94
What is the specific function of the motor cortex?
Controls voluntary movement in opposite side of body - contralateral
95
What would be the consequence of damage to the motor cortex?
Loss of control in fine motor movements
96
Where is the somatosensory cortex located?
Located in parietal lobe
97
What is the function of the somatosensory cortex?
Collects sensory information from skin
98
What is the conseuqence of damage to the somatosensory cortex?
Decreased sensation
99
Where is the visual cortex located?
Occipital lobe
100
What is the specific function of the visual cortex?
Recieves and proccesses visual information - contralateral
101
What is the consequence of damage to the visual cortex?
Blindness and not being able to recognise objects
102
Where is the auditory cortex located?
Located in the temporal lobe
103
What is the specific function of the auditory cortex?
It analyses and processes acoustic information
104
What is the consequence of damage to the auditory cortex
deafness
105
Where is Brocas area located
In frontal lobe
106
What is the specific function of Brocas area?
Speech production
107
What is the consequence of damage to Brocas area?
Talking slowly
108
Where is Wernickes area located?
Located in temporal lobe
109
What is the specific function of Wernickes area?
Speech comprehension
110
What is the consequence of damage to Wernickes area?
Loss of meaningful speech
111
What case study can be used to demonstrate localisation of function?
Phineas gage - iron rod went through his skull destroying most of left frontal lobe. He survived the accident but personality changes massively - became aggressive, vulgar, impulsive etc
112
What is the supportive evidence for localisation of function for speech comprehension and production?
Peterson et al used brain scans to show Wernickes area was active during a listening task, whereas Brocas area was active during a speaking task
Suggested 2 areas were involved in different language functions
113
What is supportive evidence for localisation of function for different types of LTM?
Tulving et al found that episodic and semantic memories were located to the temporal lobe of the brain and was demonstrated by conducting MRI scans which showed the temporal lobe was more active when these memories were accessed
114
What evidence is there against localisation of function to do with speech production?
- More areas involved in speech production than we think
- Dronkers conducted an MRI scan on Tan's brain to confirm Brocas findings, although there was a lesion in Brocas area they found evidence to suggest other areas may have contributed to the failure in speech production
115
What is the contradcictory evidence for localisation of function?
lashley found that higher, complex cognitive processes are not localised to one area but are instead more widely distributed and involve every part of the cortex
Found this by removing areas of the cortex in raiys while they were learning a maze and found no area was more important
116
What is the definition of hemispheric lateralisation?
Certain functions are controlled by one hemisphere rather than the other
117
What hemisphere is language controlled by for most right handed people?
Left hemisphere
118
What was Brocas research?
- Original case was a brain damaged patient who could only speak one word ('Tan')
- Patient could understand others speech and follow verbal instructions
- Damage was found to be localised to the base of the left frontal lobe
- Syndrome was called expressive aphasia
119
What was Wernickes research?
- Studied cases of brain damaged patients who could not understand speech
- These patients could not follow verbal instructions
- Patients could produce fluent speech but was often bizzare and meaningless
- Autopsies revealed all patients had damage to top of left temporal lobe
- This syndrome was called receptive aphasia
120
What is the difference between left and right hemisphere?
- Left hemisphere = language and is the analytic side of the brain
- Right hemisphere = recognition and is the creative side of the brain
121
What are split brain patients?
Are those who have undergon surgery to cut the corpus callosum
122
Why did people have split brain surgery?
To relieve the symptoms of severe epilspey
123
What is the effect of split brain surgery?
In these patients their two hemispheres function completely seperately as independant brains
124
What is the corpus callosum?
A thick band of nerve fibers that divide the cerebral cortex lobes into right and left hemispheres
It connects the left and right sides of the brain allowing for communication between both hemispheres
125
What was the aim of Sperrys research?
To investigate hemispheric lateralisation in split brain patients who have surgically seperated hemispheres to see whether each hemipshere is responsible for seperate functioning
126
What was the procedure of split brain patients?
- 11 epileptic males were asked complete a series of tasks which included sitting in front of a screen
- Visual stimuli tests: asked to look at fixation point in middle of the screen and where then presented with words either to the left or right of the point for 1/10 sec
- Tactile stimuli tests: participants were presented to the left or right hand behind the screen
127
What was the findings of the visual stimuli tests in sperrys research?
If a participant is presented with the word key to the right visual field they would respond with the word verbally, if it was given in the left visual field they can't respond verbally but can draw it
128
What were the findings of the tactile stimuli tests in Sperrys research?
If participants had an object placed in right hand, able to describe the object verbally
If participants had an object placed in left hand, they can't verbally describe it but can point to the correct image from pictures
129
What is the supportive evidence to lateralisation of function and what is a strengh of the research?
- Sperrys research
- The research is highly reliable - due to lab conditions
130
What is the weakness of the split brain research which supports lateralisation of function?
- Unrepresentitive - only 11 split brain patients so low population validity
- Control group did not have a history of epilepsy so can't be compared properly
- Lacks ecological validty/mundane realism as very few people have severed corpus callosum and cannot see with both eyes
131
What research can be used as a weakness of hemispheric lateralisation?
Turk et al studied a patient known as JW who suffered damage to left hemisphere but developed capacity to speak in the right hemisphere
Over time JW was able to verbalise information presented to each hemisphere of the brain - due to plasticity
132
What does plasticity mean?
Refers to the brains ability to change/adapt in response to experience or learning
133
What does 'change' mean in plasticity?
Neuronal reorganisation in the brain
134
What types of neuronal reorganisation (change) does the brain do
- Structural changes
- Functional changes
135
What are the types of structural changes does the brain do in neuronal reorganisation (plasticity)
- Axon sprouting - neurons can sprout new axons allowing new synaptic connects to be made to other neurons
- synaptic pruning - nerve pathways frequently used develop stronger connecttions, nerve pathways not often used will die out (pruning)
136
What is functional changes in the brain (plasticity)?
- Functional recovery
- After injury or illness the functions of damaged brain areas are taken over by undamaged areas
137
Explain plasticity in the new born brain
- Most rapid growth in synaptic connections
- Synaptic connections peak at around 15,000 at age 2-3 years
- This is about twice the amount in a adult brain
138
Why does the adult brain end up with far fewer synaptic connections than new borns?
With age, old, unused, weak connections are deleted - 'synaptic pruning'
Remaining connections become strenghned
Means neuronal pathways can become more refined and efficient
139
What is a hemispherectomy?
A last resort treatment for severe epilepsy that involves removing one hemisphere of the brain or disconnecting the two hemispheres
140
What did Villablanca find (plasticity)?
If a damaged hemisphere is removed soon after birth, the infant can develop into an adult with no behavioural or cognitive impairments
141
What research regarding taxi drivers supports plasticity?
- London cabbies are required to take a complex exam called the knowledge which assesses their recall of around 25,000 city streets
- McGuire found from MRI scans that the posterior hippocampus of cabbies was significantly larger in volume than a control group which were matched in IQ/education, age, handedness
- Found a positive correlation: the longer they had been doing the job, the more pronounced the difference in their brains
- Later research showed anterior hippocampus was smaller than in controls so visual memory poorer
142
What are examples of causes of brain damaged?
- Physical trauma/injury (blows to head)
- Stroke (blood vessels burst or blocked)
- Viral/bacterial infections (damages brain tissue)
143
What are the 3 ways the brain can reorganise itself? (plasticity)
- Axonal sprouting
- Neurogenesis
- Recruitment of homologous areas
144
What is axonal sprouting?
When an axon is damaged, it loses the connection with a neighouring neuron. In some cases, other axons grow new nerve endings to form extra connections and replace the lost ones to establish a new neural pathway
145
What is neurogenesis?
It is the process of forming new brain cells/neurons as well as new connections to neurons. Happens naturally through life but also occurs when brain is damaged
146
What is recruitment of homologous areas?
Recruitment of homologous areas on the opposite side of the brain to perform specific tasks. E.g if Brocas area was damaged on the left side, the equivelant area on the right side might take over language function
147
What is the supportive research for plasticity?
Kuhn 2014: Playing video games demands complex cognitive and motor skills. Grey matter in the cortex, hippocampus and cerebellum was significantly increased in participants who had been trained to play supermario for 30 min a day for 2 months
148
What are the practical applications of plasticity research?
- Has led to the development of treatments to help functional recovery
- Stem cell research may in the future make neuronal transplantation possible - stem cells be planted into the damaged areas to restore functions
- Rehabilitation techniques such as movement therapy and eletrical stimulation are used to counter some of the deficits experienced after brain damage
149
Why does functional recovery depend on a number of factors (weakness of plasticity)?
Some research suggests there are individiual differences in the extent to which the brain recovers following injury
Schneider et al found 40% patients who achieved a disability free recovery had 16+ years of education, compared to only 10% of those who had less than 12 years of education
Teuber found recovery from brain damage in soldiers were more likely in those under 20 years (60% showed significiant improvement in movement and visual problems) compared to those over 26 years 1(20% improvement)
150
Why can the effects of plasticity can be negative? (weakness of plasticity)
- In some circumstances, the brains ability to rewire itself has maladaptive behavioural consequences
- Medinal et al found prolonged use of recreational drugs causes brain reorganisation that results in poorer cognitive function, as well as increased risk of dementia
-60-80% of amputees develop phantom limb syndrome where they still experience sensations in missing limbs, which are often unpleasant/painful. This results from reorganisation in the somatosensory cortex that occurs after the loss of a limb
