biopsych Flashcards
what is the CNS?
the CNS is the central nervous system consisting of the brain and spinal chord
what is the role of the brain?
to take information in from sensory receptors (i.e. rod cells in eyes) and to send out instructions to muscles to combat instructions (move hand to put up sunglasses)
what is the role of the spinal chord?
runs along the back and consists of a network of nerves allowing for communication between the brain and the muscles
what is PNS?
PNS stands for peripheral nervous system and consists of all other nerves which aren’t CNS (brain or spine).
role of PNS?
to relay information via nerve impulses from the rest of the body back to the CNS.
what are the two subsystems of PNS?
somatic nervous system and the autonomic nervous system
what is the somatic nervous system?
includes voluntary, conscious movements, along with 12 pairs of cranial nerves and 31 pair of spinal nerves. e.g. feeling a rough/smooth surface.
what is the autonomic nervous system?
involuntary actions like heart beat. Important role in homeostasis.
what are the two subsystems of ANS?
sympathetic nervous system and parasympathetic nervous systems
what is sympathetic nervous system?
involved with emergencies e.g. fight or flight
what is parasympathetic system?
involved with restoring natural order, relaxing after an emergency
e.g. rest or digest
what is a sensory neuron?
carries impulses from sensory receptors (e.g. touch, vision and taste) to the spinal chord and brain
what is a motor neuron?
can be found in the motor cortex, responsible for indirectly/directly controlling muscles.
what are relay neurons?
a link between motor and sensory neurons for faster reactions.
describe synaptic transmission
hint: its fucking long
info is passed down the axon of a neurone as an electrical impulse known as action potential. when the electrical impulse reaches the end of the neurone it triggers vesicles to release neurotransmitters across the synapse. These then bind to receptor sites on the post-synaptic cell which then become activated.
what are the two possible neurotransmitters?
exhibitor and inhibitory neurotransmitters
what are excitatory neurotransmitters?
the nervous system’s ‘on switch; e.g. adrenaline. Causes excitation in the post synaptic neuron by increasing the positive charge and making it more likely to fire
what are inhibitory neurotransmitters?
the nervous system ‘off-switch’ causes inhibition by increasing the negative charge and making it less likely to pass on the electrical impulse e.g. serotonin
what is the endocrine system, and how does it differ from the CNS?
seperate from the nervous system it using blood vessels to deliver hormones to target sites in the body. it is slightly delayed and longer lasting in comparison to the nervous system.
role of the endocrine system?
to maintain homeostasis
describe how a hormone is released from a target gland.
hint: it’s fucking long
hypothalamus sends releasing hormone to pituitary gland which then secrets a ‘stimulating hormone’. Target gland releases its hormone in response and therefore levels of the targets gland hormone increases in the bloodstream. Hypothalamus stops secreting releasing hormone along with the pituitary gland ceasing secretion of the ‘stimulating hormone’.
describe the fight or flight response through the endocrine systems.
hint: sorta long
the hypothalamus triggers pituitary gland to release ACTH. This activates the sympathetic ns which then causes the adrenal medulla to release adrenaline, triggering the fight or flight response.
evaluation of the fight or flight response
gray (1988) states that the first response to danger is to avoid confrontation altogether which is demonstrated through a freeze response.
Taylor et al suggests women are more likely to ‘tend or befriend’ rather than fight or flee. Highlights a beta bias as psychologists assumed females acted the same as males.
what are the different ways of investigating the brain?
hint: 4
EEG, FMRI, ERP, Post Mortem
what are EEG’s?
records of electrical impulses, measures brain wave patterns.
pros of EEGs?
high ecological validity as it studies stages of sleep and involved with the diagnosis of epilepsy.
high temporal resolution as it can accurately detect brain activity at a resolution of a single millisecond.
cons of EEGs?
results are generalised as it invloves thousands of neurons, also meaning iuts not useful for pinpointing the exact source of neural activity.
what are FMRIs?
detects radio waves from changing magnetic field and focuses on neural activity. This creates a 3d image of the brain
pros of FMRIs?
non-invasive and therefore risk free
good spatial resolution (refers to the smallest feature that a scanner can detect) therefore greater accuracy in discriminating different brain regions
cons of FMRIs?
low temporal resolution (refers to how quickly the scanner can detect changes in brain activity) This makes it difficult for psychologists to predict with a high degree of accuracy as the image produced may not truly represent moment-to-moment brain activity.
what are ERPs?
use simular equipmen to EEGs. but a stimulus is presented many times and an average is graphed. The time or interval between the presentation of the stimulus and response is referred to as latency
pros of ERPs?
can measure the processing stimuli even in the absence of behavioural response. Leads to better understanding of the functioning of the brain.
can see different brain regions associated with processing info of stimuli
cons of ERPs?
lack os standardisation of methodoly, makes it harder to confirm findings.
requires intense and expensive trainiong in order to fully understand the activity measured by ERP.
what is a post mortem?
involved analysis of the brain after death to determine whether observed behaviour during a person’s life time are linked to structural abnormalities.
pros of Post Mortem?
Carl Wernicke and Paul Broca. HM’s behaviour was studied through a post mortem where damaged areas of the brain were studied and associated with his memory problems.
cons of Post Mortem?
causation issue- observed damage to the brain may not be linked to deficits, could be unrelated trauma
Ethical issues of consent as may not have been in the position to give informed consent before their death.
name/draw the 4 areas of the brain
frontal, temporal, parietal, occipital
name the areas/cortex we have studied and where they are located
broca and motor - frontal lobe
auditory and language cortex - temporal
wernicke’s cortex - temporal
somatosensory - parietal
visual - occipital
what is associated with the left hemisphere of the brain?
cognitive functions as a result of the broca and wernicke area being located there.
supporting evidence of brain function?
tulving et al found through PET scans that the left hemisphere was involved with semantic memories adn the right hemisphere was involved with episodic memories. further supported by peterson et al who found the wernickes area was activated by listening tasks and the brocas area was activated by reading tasks.
phineas cage was a worker responsible for poking in explosives with a metal rod to secure their position. One faulty dynamite flung a metal rod straight through the left side of his face, damaging his prefrontal cortex. Though he survived, there was significant change to his attitude and personality. This showed a correlation between the function of the brain and specific functions such as our personality.
limitations of brain function?
- Phineas Gage, Causation vs Correlation issue. His injuries left Phineas with blindness on his left eye and no job. One could argue that an added disability along with less finances to back you up would understandably cause significant atiitiudes changes.
- limiting functions to specific areas of the brain could be seen as having a holisitc view. For example after psycholigists removed 20-50% cortices in a rats brain, no specific area was linked to traversing a maze. This shows that the complexities of the brain (learning, new experiences) is too advanced of a cognitive ability tobe resitricted to one area.
what is the wernicke’s area?
left temporal, responsible for lang comprehension
what is the broca’s area?
left frontal lobe, speech production
what is the visual centre?
occipital lobe, visual processing
what is the motor centre?
parietal, planning controlling and carrying voluntary movements
what is the somatosensory centre?
parietal lobe, detect and process sensory info form different parts of the body and is responsible for touch, pain, temp, and pressure
what is the auditory centre?
temporal, process sounds
definition of aphasia
damage to areas of the brain results in different types of aphasia. refers to an ability to understand language or produce speech as a result of brain damage.
two types of aphasia
expressive aphasia, receptive aphasia
What is plasticity?
The brains capacity to be able adapt and change as a result of new learning and experience
Support for plasticity
examples of bad plasticity
Eleanor maguire et al (2000) studied taxi drivers and analysed their brains using MRIs. Found that there was more grey matter in their posterior hippocampus than the matched control group. This area is associated with spatial and navigational skills.
prolonged drug use leading to poorer cognitive functioning
Limitations of plasticity
Control group allows us to say that there is a significant difference between taxi drivers and others. (good design).
Use of scientific, objective measurements (MRI)
An attempt to study a real world phenomena.
We can’t be sure that the difference is due to the ‘knowledge’, they weren’t tested before. They could have been taxi drivers because of their already existing difference. (although the positive correlation between experience and structure makes this less likely)
what is functional recovery?
case study supporting func recov.
the brains ability to adapt and reallocate functions after damage or trauma to certain area
Jodi miller, left hemisphere removed as a way to calm eplieptic seizures. She was able to still control the right side of her body due to cerebal spinal fluid.
what is expressive aphasia?
otherwise known as Broca’s aphasia, people who suffer from this, struggle with speech production but have an intact language comprehension (Wernicke’s area)
what is hemispheric laterisation?
the idea that one hemisphere (half) of the brain is responsible for certain behaviours, processes etc.
who conducted split brain research and what did they do?
sperry and gazzaniga
11 epileptic patients had had their corpus callosum (a bundle of nerves connecting the left and right hemisphere together) severed and was tested in a controlled lab environment (stimulus shwon only 1/10th of a sec, one eye covered).
Presented stimulus on left field, patient would write what they say, stimulus presented on right field patient would say what they saw. This is due to the language cortex being on the left side of the brain and the visuo-spatial being on the right side.
strenghths of split brain research?
highly controlled environment
gazzaniga
provided amazing support for establishing thee different functions of the brain. going against the hollitic view of brain functions.
