Biopsychology Flashcards
What is the nervous system?
One of the main messenger systems
Complex collection of nerves and neurons that transmit signals between different ports along the way
How does the nervous system deliver messages?
Electronically through the body using synapses and neurons
What are neurons?
Specialised cells
What is the structure of the nervous system?
NS -> CNS and PNS
CNS -> spinal cord and brain
PNS -> ANS and SNS
ANS -> sympathetic NS and parasympathetic NS
What does CNS stand for?
Central Nervous System
What is the function of the CNS?
Makes complex decisions for the body
What does PNS stand for?
Peripheral Nervous System
What is the function of the PNS?
Collects sensory information
Passes information to the CNS
Carries out the actions from the CNS
What does SNS stand for?
Somatic Nervous System
What is the function of the SNS?
Control voluntary movements and skeletal muscles
What does ANS stand for?
Autonomic Nervous System
What is the function of the ANS?
Controls involuntary movements and smooth muscles
What is the function of the parasympathetic nervous system?
Calms the body to conserve and maintain energy (rest and digest)
What is the function of the sympathetic nervous system?
Arouses body to expend energy (fight or flight mode)
Are we usually in the sympathetic or parasympathetic state?
Parasympathetic
What is the function of the spinal cord?
Connects brain and PNS
In charge of reflexes
Strength of nervous system - practical application diagnosis
Anxiety disorder
Strength of nervous system - practical application treatment
Drug treatment - SSRI
AO3 nervous system - scientific
Electrical impulse measured
Limitation of nervous system - individual differences
Freeze - can’t explain why some people freeze
What is the endocrine system?
Chemical messenger of the body
What are the messages that the endocrine system sends?
Hormones
How does the endocrine system deliver messages?
Chemically through the bloodstream
What are glands?
Organs in the human or animal body which secrete particular chemical substances for use in the body or for discharge into the surroundings
What are hormones?
Regulatory substances produced in an organism and transported in tissue fluids (blood, sap) to stimulate cells or tissues into action
What is the difference between the type of signal in the nervous vs endocrine system?
N - electrical (chemical at synapse)
E - chemical
What is the difference in the transmission in signal between the nervous vs endocrine system?
N - by neurons
E - by the bloodstream
What is the difference in the effectors used in the nervous vs endocrine system?
N - muscles or glands
E - target cells in particular tissues
What is the difference in the type of response between the nervous vs endocrine system?
N - muscle contraction or secretion
E - chemical change
What is the difference in the duration of response between nervous vs endocrine system?
N - short (until nerve impulses stop)
E - long (until hormone is broken down)
What is the difference in the speed of response between the nervous vs endocrine system?
N - very rapid
E - slower
What are some examples of glands?
Thyroid
Pituitary
Ovaries
Testes
Salivary
Adrenal
Pineal
What is the hormone (and function of that hormone) that is secreted from the adrenal glands?
Adrenal – adrenaline – fight or flight (increased heart rate, increased respiration, sweating)
What is the hormone (and function of that hormone) that is secreted from the ovaries?
Ovaries – oestrogen – controls regulation of female reproductive system (menstrual cycle)
What is the hormone (and function of that hormone) that is secreted from the testes?
Testes – testosterone – responsible for development of male sex characteristics (aggression, body hair)
Strength of endocrine system - practical application diagnosis
Diabetes
Strength of endocrine system - practical application treatment
Drug treatment - insulin
AO3 endocrine system - scientific
Blood tests
Limitation of endocrine system - individual differences
Freeze - can’t explain why some people freeze
What is the role of the nervous system in fight or flight?
ANS is the main component
Typically body in parasympathetic nervous state but when ANS perceives a threat, it changes body into sympathetic nervous state
What is the role of the endocrine system in fight or flight?
Works alongside ANS
Main element of endocrine system that’s active during fight or flight is the adrenals producing adrenaline
What are the effects of the sympathetic nervous state?
Increased heart rate
Increased respiration
Sweating
Pupils dilate
Stops digestion
Stops saliva production
Contracts rectum
What are the effects of the parasympathetic nervous state?
Decreased heart rate
Decreased respiration
Constricts pupils
Starts digestion
Starts salivation
Relaxes rectum
Strength of fight or flight - practical application diagnosis
Anxiety disorder
Strength of fight or flight - practical application treatment
SSRI
AO3 fight or flight - scientific
Blood test
Limitation of fight or flight - individual differences
Some people freeze and some tend + befriend
Can’t explain those differences
What is a way to remember which diagram is the relay neuron?
Smaller
What is a way to remember which diagram is the sensory neuron?
Cell body at the side
What is a way to remember which diagram is the motor neuron?
Lollypop shape
What is the size of a sensory neuron’s dendrites?
Long
What is the size of a sensory neuron’s axon?
Short
What is the function of the sensory neuron?
Receives/collects sensory information
Where are sensory neurons located?
Peripheral Nervous System
What is the size of a relay neuron’s dendrites?
Short
What is the size of a relay neuron’s axon?
Short
What is the function of relay neurons?
Decision-maker
Sensory-motor connector
Carries complex decisions
Where are the relay neurons located?
Central Nervous System (mainly brain)
What is the size of a motor neuron’s dendrites?
Short
What is the size of a motor neuron’s axon?
Long
What is the function of motor neurons?
Actions decisions through effectors
Where are motor neurons located?
Peripheral Nervous System
Strength of neurons - practical application diagnosis
Motor neurone disease
Strength of neurons - practical application treatment
Pacemaker in brain
AO3 neurons - scientific
Electrical impulse measured
Limitation of neurons - individual differences
Freeze - some people freeze
What are dendrites?
Branch-like structures which carries impulses to the cell body
What is an axon?
Carries impulses away from the cell body down the length of the neuron
What are terminal buttons?
Communicates with the next neuron over the synapse
What are vesicles?
Contain the neurotransmitters
What are neurotransmitters?
Chemicals that diffuse across the synapse to the next neuron
What is the beginning stage of synaptic transmission?
An ELECTRICAL IMPULSE is passed down the pre-synaptic neuron (axon)
Pre-synaptic neuron gets the vesicles to release neurotransmitters
What is the middle stage of synaptic transmission?
Neurotransmitters passed to the synapse via the terminal buttons
Then CHEMICALLY diffuse through the synapse
What is the end stage of synaptic transmission?
Neurotransmitters collected by the receptor sites of the post-synaptic neuron (dendrite)
Return to an ELECTRICAL STATE
Send an electrical impulse down the post-synaptic neuron (dendrite)
What is the fourth mark for a synaptic transmission question?
SUMMATION - totals/adds up the electrical charge of neurotransmitters
What are the two different types of neurotransmitter?
Excitation
Inhibition
What charge does an excitation neurotransmitter increase?
POSITIVE charge of postsynaptic charge
Does an excitation neurotransmitter increase or decrease the likelihood of the neurons firing?
Increase
What is an example of excitation neurotransmitter?
Dopamine
What charge does an inhibition neurotransmitter increase?
NEGATIVE charge of postsynaptic charge
Does an inhibition neurotransmitter increase or decrease the likelihood of the neurons firing?
Decrease
What is an example of an inhibition neurotransmitter?
Serotonin
What is summation?
Post-synaptic neuron adds up the charge of the excitation and inhibition neurotransmitters that have been passed and calculates whether overall the post-synaptic neuron is in an excitatory or inhibitory state
Strength of synaptic transmission - practical application diagnosis
Parkinsons
Strength of synaptic transmission - practical application treatment
Pacemaker in brain
AO3 synaptic transmission - scientific
Electrical impulse measured
Limitation of synaptic transmission - individual differences
Freeze - can’t explain why some people freeze rather than fly
What is localisation of function?
Each brain area has a specialised function, which is unique to that brain area
What side of the body is the left hemisphere in charge of?
Right hand side of the body
What side of the body is the right hemisphere in charge of?
Left hand side of the body
What the different areas of the brain that are named in the specification for localisation?
Motor cortex
Somatosensory cortex
Visual cortex
Auditory cortex
Broca’s area
Wernicke’s area
Where is the motor cortex located?
Back of the frontal lobe
Both hemispheres
What is function of the motor cortex?
In charge of movement
What happens in the motor cortex is damaged?
Paralysis
Where is the somatosensory cortex located?
Front of parietal lobe
Both hemispheres
What is the function of the somatosensory cortex?
Process sensory information (pain, heat)
What happens in the somatosensory cortex is damaged?
Numbness (loss of sensation)
Where is the visual cortex located?
Back of the occipital lobe
Both hemispheres
What is the function of the visual cortex?
Processes visual information
What happens if the visual cortex is damaged
Blindness
Where is the auditory cortex located?
Middle of the temporal lobe
Both hemispheres
What is the function of the auditory cortex?
Processes auditory information
What happens if the auditory cortex is damaged?
Deafness
What are the two language centres?
Broca’s area
Wernicke’s area
Where is Broca’s area located?
Frontal lobe
LEFT hemisphere ONLY
What is the function of Broca’s area?
Speech production
What happens if Broca’s area is damaged?
Slow, stuttered speech
May be incapable of saying certain words (Broca’s aphasia)
Where is Wernicke’s area located?
Back of the temporal lobe
LEFT hemisphere ONLY
What is the function of Wernicke’s area?
Speech comprehension
What happens if Wernicke’s area is damaged?
Produce nonsense words (Wernicke’s aphasia)
fMRI scanning task
Strength of localisation - research support
Peterson et al
Used brain scans to demonstrate how Wernicke’s area was active during listening task
Broca’s area active during reading task
Strength of localisation - Phineas Gage case study
Had metre-length pole go through his head, taking most of his left frontal lobe
He turned from someone who was calm and reserved to someone rude and quick tempered
Limitation of localisation - Lashley’s research
Removed areas of rat’s cortex (between 10-50%) that were learning a maze
No area proven more important
Process of learning required every part of cortex
Counterargument localisation - Lashley’s research - extrapolation and ethics
Rat brains and human brains are different
Can’t replicate on humans
Strength of localisation - practical application
Diagnosis
Doughtery et al
- 44 OCD patients who had undergone neurosurgical procedure involving lesioning of the cingulotomy gyrus
- after 32 weeks, 1/3 reported successful response and 14% reported partial response
Strength of localisation - scientific
Has a scientific method
What is hemispheric lateralisation?
Belief that each hemisphere has a specific function/responsibility
What are the functions of the left hemisphere?
Verbal/speech
Right field vision
Right side motor skills
What are the functions of the right hemisphere?
Perception
Left field vision
Left side motor skills
Who conducted split-brain research?
Sperry
What was the sample of split-brain research?
11 patients with a dissected corpus callosum
What is the procedure of the split-brain research?
An image would flash for 10th of a second
Patients would be staring at the fixation point in the middle of the two images
Tree on the left, car on the right
What were the results of the split-brain research?
Car - right visual field - left hemisphere - speak
Tree - left visual field - right hemisphere - draw with left hand
Strength of split-brain procedure - replicable
Standardised procedure
Limitations of split-brain procedure - sample
Small sample size
Lack of ecological validity
Confounding variable of epilepsy
Confounding variable of different levels of dissection
Strength of lateralisation - Lashley rat study
Removed areas of rat’s cortex (between 10-50%) that were learning a maze
No area proven more important
Process of learning required every part of cortex
What is plasticity?
Brain’s ability to change and adapt because of experience
Brain continues creating new neural pathways and altering existing ones in response to changing experiences
What is synaptic pruning?
Rarely-used connections deleted
Frequently-used connections strengthened
What is functional recovery?
Transfer of functions from a damaged area of the brain after trauma to other undamaged areas
What are the ways that the brain can recover function?
Opposite brain area can take over the function
Building new synaptic connections
Reconnecting blood vessels to the damaged area
What is neuronal unmasking?
“dormant” synapses (haven’t received enough input to be active) open connections to compensate for a nearby damaged area of the brain
Allows new connections in the brain to be activated, recovering any damage occurring in specific regions
Strength of plasticity and functional recovery - practical application
Neurorehabilitation
Create treatments to speed up this process
Recovery after a stroke etc
Limitation of plasticity and functional recovery - phantom limb syndrome
Negative plasticity
For some patients who lose a limb, they experience phantom limb syndrome - able to feel their missing limb
Happens in 60-80% of cases
Occurs because brain is reforming and causes another body part to take over the brain area of missing limb causing sensations to occur
Strength of plasticity and functional recovery - research support
McGuire taxi study
Studied brain of London taxi drivers who had to learn every road, land mark and route in London
Posterior hippocampus was larger than control group
Strength of plasticity and functional recovery - scientific
It has a scientific method
Replicable
Strength of plasticity and functional recovery - animal studies
Hubel and Wiesel
Sewed one of a kitten’s eyes shut then conducted brain scans on the cat
Found the visual cortex of the ‘shut eye’ remained processing as it was processing information from the other eye
What are the four ways of studying the brain?
FMRI (Functional Magnetic Resonance Imaging)
EEG (electroencephalograms)
ERP (event-related potentials)
Post-mortem
What is spatial resolution?
How much detail the brain scan produces/whether it can investigate the whole brain
What is temporal resolution?
Whether the brain scan produces a live feed of the brain’s activity rather than a static image
What is an FMRI?
Detects the blood and oxygen levels of the brain
Brighter the image, the more activity
What does an FMRI produce?
3D image of the brain = activation map
What are the advantages of FMRIs?
High spatial resolution
Risk free - no radiation
What are the disadvantages of FMRIs?
Low temporal resolution
Expensive
What is an EEG?
Measures GENERAL ELECTRICAL ACITVITY within the brain via electrodes that can be placed either on the scalp (skull cap) or on the brain
What does an EEG produce?
Scan recording showing electrical activity from millions on neurons
What are the advantages of EEGs?
High temporal resolution
Practical uses
What are the disadvantages of EEGs?
Low spatial resolution
Information generalised
Source not pinpointed
What is an ERP?
Measures ELECTRICAL ACTIVITY IN RESPONSE to a specific stimulus
Use same method of EEG then delete general brain activity
What does an ERP produce?
Scan recording
What are the advantages of ERPs?
High temporal resolution
Specificity
What are the disadvantages of ERPs?
Low spatial resolution
Lack of standardisation
Background ‘noise’ - must be completely eliminated
What is a post-mortem?
Analysis of brain after death
Check weight, look for any damage/structural abnormalities, check neurotransmitter levels, cut brain up to see every part
What does a post-mortem produce?
Detailed written report on several aspects of the brain
What are the advantages of post-mortems?
High spatial resolution
Localisation
Medical research
What are the disadvantages of post-mortems?
Low temporal resolution
Knowing causations
What are biological rhythms?
Cyclical within biological systems that have evolved in response to environmental influences
What are exogenous zeitgebers?
External factors which influence biological rhythms
What are examples of exogenous zeitgebers in relation to the sleep/wake cycle?
Light
Social cues (eating, exercise)
How does light affect the sleep/wake cycle?
Helps the brain know whether it’s day or night
Effects it by activating the release of certain process
What is the process through which exogenous zeitgebers influence biological rhythms?
Entrainment
What is entrainment?
The process of the exogenous zeitgebers affecting biological rhythms (sleep/wake cycle)
External factors can change the sleep/wake cycle pattern
Strength of exogenous zeitgebers - practical application
Lights on phones
Can turn on night light to stop light and make body get ready to sleep
Strength of exogenous zeitgebers - research support
Campbell and Murphey
15 participants slept with a light pad under their knee
By flashing a light behind their knee, managed to change their sleep/wake cycle by up to 3 hours
Limitation of exogenous zeitgebers - individual differences
In some Artic regions of world, exposed to light 24/7 as sun doesn’t set
Sleep/wake cycle should be affected by constant light but have normal sleep/wake cycle
What are endogenous pacemakers?
Internal factors that influence biological rhythms
What is the main endogenous pacemakers that affects the sleep/wake cycle?
SCN
What is the SCN?
Part of the brain which receives light information
Information passed to the pineal gland to produce melatonin to make us feel sleepy
Strength of endogenous pacemakers - research support
DeCoursey
Removed SCN of 20 chipmunks and released them into the wild
Sleep/wake cycle disappeared
Many killed by predators
Limitation of endogenous pacemakers - use of animal studies
Extrapolation
Cannot generalise animal findings to humans
Humans are more complex
Strength of endogenous pacemakers - Ralph et al
Trained hamsters to have 20 hour cycle
Removed the 20 hr cycle SCN and placed them into a 24 hr hamster’s brain
Developed cycles of 20 hrs
What are the three biological rhythms?
Circadian
Infradian
Ultradian
What is a circadian rhythm?
Any biological rhythm that lasts roughly 24 hours
What are the two main examples of circadian rhythms?
Sleep/wake cycle
Body temperature
What is the sleep/wake cycle?
Dictates when humans and animals should be asleep or awake
Recommended sleep for 17 year old = 8-10 hours
Recommended awake time for 17 year old = 14-16 hours
What is the body temperature circadian rhythm?
Human body temperature is at its lowest in early hours of the morning and at its highest in early evening
Sleep typically occurs when core temperature starts to drop
Body temperature starts to rise towards end of sleep cycle, promoting feelings of alertness first thing in the morning
Strength of circadian rhythms - research support
Siffre
Spent long periods in dark caves to examine effects of free-running biological rhythms (2 and 6 months)
Absence of external cues significantly altered circadian rhythms
When returned from underground stay with no clock or light, believed date to be a month earlier than it was
24 hr sleep/wake cycle increased by lack of cues, making him believe it was longer than it was so fewer days had passed
Limitation of circadian rhythms - individual differences
Duffy et al
“Morning people” prefer to rise and go to bed early (6am-10pm)
“Evening people” wake and go to bed later (10am-1am)
Innate individual differences
Strength of circadian rhythms - practical application
Times when taking medication is more effective than others
Heart attacks more likely to happen on a Monday morning so medication needs to be most effective during this time
What are infradian rhythms?
Any biological rhythm that is longer than 24 hours
What is an example of a weekly infradian rhythm?
Blood pressure
What is an example of a monthly infradian rhythm?
Menstrual cycle
What is an example of a yearly infradian rhythm?
Seasonal Affective Disorder (SAD)
How long is a normal menstrual cycle on average?
28 days
What are the hormones involved in the menstrual cycle?
Oestrogen
Progesterone
SFH
LH
When does a menstrual cycle start?
First day of bleeding
How many stages are there in the menstrual cycle?
4 stages
What happens in the menstrual cycle?
Regulated by hormones that either promote ovulation or stimulate uterus for fertilisation
Ovulation occurs roughly half-way through the cycle when oestrogen levels are at their highest and usually lasts for 16-32 hrs
After ovulatory phase, progesterone levels increase in preparation for possible implantation of embryo in uterus
What is Seasonal Affective Disorder?
Type of depression that comes and goes in a seasonal pattern
Symptoms usually more apparent and severe during winter
Few people with SAD may have symptoms during summer and feel better in winter
Strength of infradian rhythms - practical application
Now have clear understanding of “typical” menstrual cycle and can diagnose any problem
Created treatments to help
IVF for couples with fertility issues
Limitation of infradian rhythms - confounding variables
Criticised early synchronisation studies
Confounding variables of stress, diet and exercise
Most research based on self-report (demand characteristics and social desirability bias)
Strength of infradian rhythms - research support
“Sweaty Betty study”
Stern and McClintock
Investigated menstrual synchrony
Got swabs of sweat from women with a regular cycle and wiped the sweat onto the upper lip of women who had an irregular cycle
Menstrual cycles synched
Limitation of infradian rhythms - evolutionary disadvantage
Schank
If females were all fertile at the same time, they would fight for the “best male”
Women who then have to settle for “less quality” males which would put their children at a disadvantage
Better if women didn’t synch
Strength of infradian rhythms - scientific
Scientific method
What are ultradian rhythms?
Any biological rhythm that’s shorter than 24 hours
What is the main example of an ultradian rhythm?
Sleep cycle
How long is the sleep cycle?
90 minutes
How many stages are there in the sleep cycle?
5
What happens in terms of brain waves in the different stages of the sleep cycle?
Stage 1 and 2 = brainwaves are slower going from alpha waves to even slower theta waves
Stage 3 and 4 = start to have delta waves which are slower, this is slow wave sleep
Stage 5 (REM) = high correlation with dreaming
What happens in stage 1 of the sleep cycle?
Light sleep
Muscle activity slows down
Occasional muscle twitching
What happens in stage 2 of the sleep cycle?
Breathing pattern and heart rate slows
Slight decrease in body temperature
What happens in stage 3 of the sleep cycle?
Deep sleep begins
Brain begins to generate slow delta waves
What happens in stage 4 of the sleep cycle?
Very deep sleep
Rhythmic breathing
Limited muscle activity
Brain produces delta waves
What happens in the stage 5 of the sleep cycle?
Rapid eye movement (REM)
Brainwaves speed up and dreaming occurs
Muscles relax
Heart rate increases
Breathing is rapid and shallow
Strength of ultradian rhythms - practical application
Diagnose sleep disorders
Insomnia = people find it difficult to fall asleep or staying asleep
Spell apnoea = breathing becomes partially or completely obstructed during sleep
Sleep bruxism = grinding of teeth involuntarily during sleep
Limitation of ultradian rhythms - individual differences
Tucker et al
Studied participants over 11 days in a lab study
Found large individual differences in sleep duration, time to fall asleep and amount of time in each sleep stage
Night owl/early bird
Strength of ultradian rhythms - research support
Dement and Kleitman
Monitored sleep patterns of 9 adults in sleep lab with caffeine and alcohol controlled for
Found correlations between REM activity and experience of dreaming
Some participants woken during REM sleep could vividly report their dreams
