PAPER 2 - Biopsychology Flashcards
What are the two divisions of the Human Nervous System ?
The Central Nervous System (CNS)
The Peripheral Nervous System (PNS)
What makes up the CENTRAL NERVOUS SYSTEM ?
the BRAIN and SPINAL CORD
What makes up the PERIPHERAL NERVOUS SYSTEM ?
NERVE CELLS - carry information to / from CNS
Within the CNS is the brain and spinal cord. What is the BRAIN responsible for ?
PHYSIOLOGICAL processes
Within the CNS is the brain and spinal cord. What is the SPINAL CORD responsible for ?
RECEIVING / TRANSMITTING information to / from the brain to PNS
reflex actions
What are the two systems within the PNS ?
SOMATIC and AUTONOMIC nervous systems
What does the SOMATIC NERVOUS SYSTEM do ?
- voluntary acts
- receives info from SENSORY RECEPTORS
- sends info to CNS = controls muscle movement
What does the AUTONOMIC NERVOUS SYSTEM do ?
- involuntary acts
- heart rate
- digestive system
What are the two sub divisions within the Autonomic Nervous System ?
SYMPATHETIC and PARASYMPATHETIC nervous systems
What does the SYMPATHETIC NERVOUS SYSTEM do ?
- prepares body for emergency situation
- increases HR / blood pressure / vasodialation
What dies the PARASYMPATHETIC NERVOUS SYSTEM do ?
- relaxes body
- decreases HR / blood pressure
What are NEURONS ?
- building blocks of nervous system
- transmit messages
- electrical and chemical signals
What are DENDRITES ?
- end of neuron
- receive signals (neurons / sensory recpetors)
What are dendrites connected too ?
cell body
What is connected to the cell body ?
axon
What is the axon covered in ?
myelin sheath - protects axon and speeds up electrical impulse
What is at the end of the axon ?
terminal buttons
What do TERMINAL BUTTONS do ?
communicate with the next neuron
What is the gap between neurons called ?
synapse
What are SENSORY NEURONS ?
- carry messages from SENSORY RECEPTORS
- convert messages to neural impulses
What is the structure of sensory neurons ?
LONG dendrites and SHORT axon
What are RELAY (INTER) NEURONS ?
- connect sensory to motor
- allow communication between neurons
- found in CNS
What is the structure of relay neurons ?
SHORT dendrites and SHORT axon
What are MOTOR NEURONS ?
- connect CNS to MUSCLES and GLANDS
- control muscles (directly and indirectly)
- release neurotransmitters = trigger response
What is the structure of motor neurons ?
SHORT dendrites and LONG axon
What is the structure / order of neurons ?
sensory receptors - dendrites - cell body - axon - terminal buttons - next neuron - CNS
What are NEUROTRANSMITTERS ?
CHEMICALS that DIFFUSE across the SYNAPSE to the NEXT NEURON
What is EXCITATION ?
leads to POST SYNAPTIC neuron becoming POSITIVELY CHARGED = MORE likely to fire
e.g. ADRENALINE
What is INHIBITION ?
leads to POST SYNAPTIC neuron becoming NEGATIVELY CHARGED = LESS likely to fire
e.g. GABA
What is the ENDOCRINE SYSTEM ?
- second system
- made up of specialist glands
- glands release hormones
- hormones transmit messages
Name 4 endocrine glands
- thyroid
- pineal
- adrenal medulla
- adrenal cortex
What does the thyroid gland hold and its effects ?
THYROXINE
- metabolic rate
- growth rate
What does the pineal gland hold and its effects ?
MELATONIN
- arousal
- biological rhythms
- sleep-wake cycle
What does the adrenal medulla gland hold and its effects ?
ADRENALINE & NORADRENALINE
- fight / flight
- heart rate
- blood flow
- release glucose and fat
What does the adrenal cortex hold and its effects ?
GLUCO-CORTI-COIDS
- further release of glucose
- suppression of immune system
- inflammatory response
What is the FIGHT / FLIGHT RESPONSE ?
- generate from autonomic nervous system
- reflex response
- increases reaction time
- facilitates OPTIMAL FUNCTIONING
What is the process of the fight / flight response ?
stressful event | hypothalamus - send message to... | pituitary gland - which releases... | adreno-cortico-trophic hormone (ACTH) - causes adrenal glands to release... | adrenaline - this triggers... | fight / flight response
FLIGHT / FIGHT RESPONSE: hypothalamus send message to the…
PITUITARY GLAND
FIGHT / FLIGHT RESPONSE: pituitary gland releases…
ADRENO-CORTICO-TROPHIC HORMONE
FIGHT / FLIGHT RESPONSE: adrenocorticotrophic causes the adrenal glands to release…
ADRENALINE
FIGHT / FLIGHT RESPONSE: adrenaline causes physiological changes, leading to the…
FIGHT / FLIGHT RESPONSE
FIGHT/ FLIGHT RESPONSE: after the stress is over the … is activated
PARASYMPATHETIC BRANCH `
What are the 6 locations in the brain ? (MSVWAB)
motor cortex somatosensory cortex visual cortex wernicke's area auditory cortex broac's area
What lobe is Broac’s area in ?
FRONTAL
What lobe is the motor cortex in ?
FRONTAL
What lobe is the somatosensory cortex in ?
PARIETAL
What lobe is the visual cortex in ?
OCCIPITAL
What lobe is the Wernicke’s area in ?
TEMPORAL
What lobe is the auditory cortex in ?
TEMPORAL
Define LOCALISATION OF FUNCTION
the concept that different parts of the brain are responsible for INDIVIDUAL and DISCRETE functions
What is the MOTOR CORTEX responsible for ?
voluntary muscle movement e.g. getting a glass of water
What is the SOMATOSENSORY CORTEX responsible for ?
processes sensory input from the skin, muscles and joints related to touch - produces sensations of touch pressure, pain and temp
What is the VISUAL CORTEX responsible for ?
vision - processing colour, shape, size
What is the AUDITORY CORTEX responsible for ?
hearing - volume, pitch, location of sound
What is the WERNICKE’S AREA responsible for ?
understanding language
What is the BROCA’S AREA responsible for ?
producing speech / expressing thoughts through writing
What are the common symptoms of aphasia ?
problems with…
- reading
- listening
- speaking
- writing / typing
What are the common causes of aphasia ?
- stroke (most common)
- severe head injury
- brain tumour
- progressive neurological conditions
What is LOCALISATION ?
different areas of the brain being responsible for specific functions
What is LATERALISATION ?
the idea that different hemispheres have different specialisations
What is BROCA’S APHASIA ?
inability to articulate speech fluently - disjointed words - understanding of speech is normal
What is WERNICKE’S APHASIA ?
breakdown in the ability to understand speech - sentences are deficient in meaning
How do Broca’s and Wernicke’s areas interact ?
sensory region picks up audio / visual input - Wernicke’s recognises language and associates the meaning - Broca’s area identifies what speech needs to be produced - speech produced
What are the STRENGTHS of localisation of functions ?
SUPPORT RESEARCH
- Petersen et al = brain scans
- W area active in listening task
- B area active in reasoning task
SUPPORT RESEARCH
- Emmorey = spoken / sign language
- both activated B area
- Hickok - damage to W affects understanding of sign
PRACTICAL APPLICATIONS
- stroke victims
- can work out damaged area from symptoms
- develop treatment
What are the WEAKNESSES of localisation of functions ?
COUNTER RESEARCH
- Danelli - case study
- EB = left hemi removed at 2 due to tumour
- intensive rehab helped regain speech
- demonstrates brain plasticity
METHODOLOGY
- research based on case studies
- individuals reacts to stroke and treatment in different ways
- hard to generalise
Define BRAIN LATERALISATION
two halves of the human brain are not exactly alike - each hemisphere has functional specialisms
Who carried out split brain research ?
SPERRY (1968)
What is split brain research ?
observing people who had had their corps callosum cut down the middle to separate the two hemispheres - treat epilepsy
Why was split brain research carried out ?
to test the capabilities of each hemisphere when separated
What are the STRENGTHS of split brain research ?
SUPPORT RESEARCH
- Rasmussen and Miller
- L hemisphere more concerned with language
- R hemisphere more concerned with spatial / artistic
METHODOLOGY
- high control
- Sperry = stopped natural tendency for pp to move their eye
- stimulus presented for 200 milliseconds
What are the LIMITATIONS of split brain research ?
METHODOLOGY (counter argument for the strength)
- low ecological validity
- we would usually use both eyes everyday
POPULATION VALIDITY
- 11 males
- differences in the operations
- cannot develop model of hemispheric lateralisation
COUNTER EVIDENCE
- turk et al = JW - was able to speak out R hemisphere
- brain can adapt / plasticity
What is brain PLASTICITY ?
the ability of the brain to CHANGE AND ADAPT, synapses, pathways and structures in light of various experiences
What is plasticity like in childhood ?
by the end of the first year the brain will have MORE NEURONS than it will ever have
as we get older our brain is SCULPTURED by our ENVIRONMENT and EXPERIENCES
What is SYNAPTIC PRUNING ?
pathways and networks that aren’t used will die off
When does brain plasticity stop ?
neural connections can change at ANY AGE as a result of new learning and experiences
What research was done into brain plasticity ?
MAGUIRE ET AL
- london taxi drivers
- 16 male taxi / 50 male non-taxi
- POSTERIOR HIPPOCAMPUS (spatial skills) larger
- correlation between years as taxi driver and volume of hippocampus
What is FUNCTIONAL RECOVERY ?
a form of plasticity whereby other areas of the brain take over the functions of the damaged area
How does functional recovery occur ?
- axon sprouting
- denervation super sensitivity
- recruitment of homologous (similar) areas
What is AXON SPROUTING ?
the AXONS of SURVIVING NEURONS grow new BRANCHES that make SYNAPSES in areas of the brain formerly supplied by damaged neurons
What is DENERVATION SUPER SENSITIVITY ?
this occurs when axons that DO A SIMILAR JOB become AROUSED TO A HIGHER LEVEL, to COMPENSATE for the ones that are lost
What is RECRUITMENT PF HOMOLOGOUS AREAS ?
example: Broca’s area was damaged - the right side equivalent would take over.
What research was done into functional recovery ?
DANELLI
- EB - left hemisphere removed at 2
- intensive rehabilitation = regain ability to speak
- 17 years, language was comparable to ‘normal’ controls
What are the STRENGTHS of brain plasticity and functional recovery ?
PRACTICAL APPLICATIONS
- therapy e.g. movement therapy
RESEARCH EVIDENCE
- draganski et al - students before and after finals
- posterior hippocampus
- mechelli et al - bilingual = larger parietal cortex
- schneider et al - college education less likely to have a disability after trauma = cognitive reserve
What are the WEAKNESSES of brain plasticity and functional recovery ?
NOT STRAIGHT FORWARDS
- speech requires a lot of effort = fatigue
- can be affected by other factors e.g. stress and alcohol
GENDER
- women better at attention / memory / language
- men better at visual analytical skills
- questions extent
What is an fMRI ?
- records energy released by haemoglobin
- active area = more oxygen
- 1sec time difference (temporal resolution)
What are the STRENGTHS of fMRI’s ?
NON-INVASIVE
- nothing is inserted into body
- no brain exposure
- more ethical
OBJECTIVE
- no verbal report
- not affected by researcher bias
What are the LIMITATIONS of fMRI’s ?
IMPRACTICAL
- expensive
- patient must be still for clear image
- uncomfortable
- temporal resolution
What is the full name of an fMRI ?
Functional Magnetic Resonance Imaging
What is an EEG ?
- measures electrical activity in the brain
- electrodes detect small electrical changes
- shown on graph
- used to show neurological abnormalities - epilepsy
What is the full name of an EEG ?
Electroencephalogram
ELEC TROEN CEPH ALOGRAM
What are the STRENGTHS of an EEG ?
ACCURACY
- real time
NON-INVASIVE
What are the WEAKESSES of an EEG ?
NOT SPECIFIC ENOUGH
- gives general overview
- cannot pinpoint exact source of activity
SURFACE MEASUREMENT
- superficial regions of the brain - not very deep
- limited in what we can study
What is an ERP ?
- more specific than EEG
- uses statistical averaging techniques to filter put extraneous brain activity
What is the full name of an ERP ?
Event-related Potentials
What are the STRENGTHS of an ERP ?
ACCURACY
- continuous measurement
- able to determine how processing is affected by experimental manipulations
DEMAND CHARACTERISTICS
- response to stimuli is measured without individual giving a response
What are the WEAKNESSES of an ERP ?
SURFACE MEASUREMENT
- only detects neural activity of a certain strength
What is a POST-MORTEM EXAMINATION ?
- see where damage has occurred
- happen on people who had rare disorders
- establish link between psychiatric disorders and brain abnormalities
What are the STRENGTHS of post-mortems ?
FULL ACCESS TO THE BRAIN
- detailed / deeper area
- hypothalamus / hippocampus
What are the WEAKNESSES of post-mortems ?
LACK OF CONTROL
- confounding variables e.g. cause of death
- influence results
RETROSPECTIVE
- issues with establishing causation
- observed damage may not be a result of the suspected cause
What is a BIOLOGICAL RHYTHM ?
- something in the body that follows a regular cycle
What is a biological rhythm governed by ?
endogenous pacemakers
exogenous zeitgebers
What are ENDOGENOUS PACEMAKERS ?
body’s internal biological ‘clocks’
What are EXOGENOUS ZEITGEBERS ?
external changes in the environment
What are CIRCADIAN RHYTHMS ?
- lasts 24 hours
- sleep / wake cycle
- regulated by release of hormones / metabolic rate / body temp
What are the STRENGTHS of circadian rhythms ?
SUPPORT RESEARCH
- folkard et al
- 12 pp lived in a dark cave for 3 weeks
- gradually sped up clock 24 hr to 22 hr
- none of the pp could adjust
PRACTICAL APPLICATIONS
- shift work
- consequences of adjusting cycle (3x heart disease)
What are the LIMITATIONS of circadian rhythms ?
INDIVIDUAL DIFFERENCES
- duffy
- rise early or go to bed late
- despite EPs being innate there are some variations
METHODOLOGY
- poor control
- pps were isolated from variables that might affect their circadian rhythms except artificial light
- artificial light may be confounding variable
METHODOLOGY
- small sample size
- individual differences
What is the SCN ?
- regulated by light
- allows biological clocks to adjust to changing patterns of daylight
- built in circadian rhythm
Where is the SCN located ?
hypothalamus
What research was done in to the SCN ?
- ralph et al - removed SCN from genetically abnormal hamsters
- put into normal hamsters
What is the PINEAL GLAND ?
- receives signals from SCN
- increases melatonin at night
- inhibits brain mechanisms
How do SOCIAL CUES affect the sleep / wake cycle ?
- mealtimes
- adapting to local times of eating when travelling changes circadian rhythms
What research evidence has been done on social cues ?
klein and wegmann - jet lag - adjust better when they go outside
What are the STRENGTHS of endogenous pacemakers and exogenous zeitgebers
RESEARCH EVIDENCE
- siffre - cave - no light - 179 days - circadian rhythm increased past 24 hrs
PRACTICAL APPLICATIONS
- jet lag - shift work - increased car accidents and heart disease - help improve lifestyle - long periods om same shift routine
What are the LIMITATIONS of endogenous pacemakers and exogenous zeitgebers
METHODOLOGY
- siffre - small sample size - repeated when 60 - internal clock was slower - hard to generalise
METHODOLOGY
- artificial environments - endogenous pacemakers and exogenous zeitgebers interact in real life
CONFLICTING RESEARCH
- arctic circle - 6 month light / 6 month no light - maintain sleep cycle
What are INFRADIAN RHYTHMS ?
longer than 24 hours
What is an example of a monthly cycle ?
menstrual cycle - mainly endogenous (hormones)
What is the menstrual cycle ?
- monthly changes in hormone levels
- oestrogen develops egg
- progesterone rise = thinker lining
- womb lining sheds
What research has been done into the menstrual cycle ?
McClintock
- 29 women
- odourless compounds from armpit of other women
- 68% cycle became closer to ‘odour donor’
- shows exogenous affects
What is an example of an annual cycle ?
Seasonal Affective Disorder (SAD) - mainly endogenous (light)
What is SAD ?
- occur in winter months
- persistent low mood
- lack of sunlight = more melatonin produced
- effects production of serotonin
What is an ULTRADIAN RHYTHM ?
less than one day e.g. sleep cycle
What is BRAC ?
Kleitman
- 90 min ultradian rhythm continues in day
- periods of alertness
- periods of fatugue
- human mind can focus for 90 mins
What are the STRENGTHS of infradian and ultradian rhythms ?
RESEARCH EVIDENCE
- 9 pps
- EEG during sleep
- everyone had REM sleep
- those woken in REM were more likely to remember dreams
PRACTICAL APPLICATIONS - SAD - lightbox - reset melatonin - relieved 60% of sufferers however - placebo effect of 30%
What are the LIMITATIONS of infradian and ultradian ?
INDIVIDUAL DIFFERENCES
- assessed sleep duration / time to fall asleep / amount of time in each stage
- large differences in each stages especially 3 and 4
CONFLICTING EVIDENCE
- 186 chinese women
- dorms together
- periods did not sync
