Biopsych Flashcards
(42 cards)
What is the CNS made up of?
Brain
Spine: responsible for reflex action
What is the PNS made up of?
Somatic nervous system: governs muscle movement and receives info from sensory receptors
Autonomic Nervous system: governs vital bodily functions e.g. breathing and sympathetic/ parasympathetic response
what is the endocrine system role/ made up of?
works alongside nervous system
works through chemicals and glands
Thyroid: thyroxine; motabolism/growth
Pituitary: governs all other glands
Adrenal: adrenaline; fight or flight
What are the 3 types of Neuron and their structure?
Sensory: long dendrites, short axon
Relay: short dendrite, short axon
Motor: short dendrites, long axon
What is the structure of a neuron?
Dendrites receive and impulse from neigbouring cells and pull it towards the cell body. The axon covered by the Meylin sheith with nodes of Ranvier the impulse has to jump across, carries the message to the terminal button
What is action potentual?
A neurons resting state is negative. When it is acticated by a stimulus is becomes positive for a split second causing an action potential to occur creating the electrical impulse that is carried down the axon
how does Synaptic transmission occur?
Synaptic vesicals fuse to the wall of the presynaptic terminal and release neurotransmitters into the synaptic cleft. The neurotransmitters diffuse accross the gap to be picked up by the post synaptic receptor sites. some Neurotransmitters will be reuptaked back into the presynaptic terminal, some will be destroyed by enzymes
What is summation?
whether a neuron fires is determined by if the sum of the influences effected on it is net positive
what is Excitation and Inhibition?
Some neurotransmitters, like adrenaline, are excitory making the neuron more positive, some, like seritonin, are inhibitory, making the neuron more negative
what is localiseation of function?
The theory that different areas of the brain are resposible for spesific behaviours, processes or activities
what are the localised funtions of the brain?
Motor area: Frontal lobe. Damage causes loss of control over fine motor movements
Somatosensory: parietal lobe. damage causes loss of feeling
Visual: occipital lobe. damage causes partial blindness
Auditory: temporal lobe. damage can cause partial hearing loss
Broca’s area: left frontal lobe. Damage causes Broca’s aphasia charactorised by slow, laboureous, influid speach
Wernickes area: left temporal lobe. Damage causes Wernicke’s aphasia characterised by production of neolisms (nonsense words) in speach
Evaluate localisation of function
+ neurosurgery support
> Dougherty et al had 44 patents with OCD get a cingulotomy (isolating an area of the brain). 33% were successful meaning OCD is implicated with spesifically that area of the brain
+ brain scans
Peterson et al demonstrated wernicke’s area was active during spesific tasks
CA: Lashley took out 10%-50% of a rats brain then had them find their way out of a maze and it made no difernce
- Language may not be limited to Brocc and Wernicke’s areas.
> advances in brian imiging technique has found language processes in different areas of the brain
What is hemispheric lateralisation?
The4 idea that the two halves of the brain are funtionally different.
some functions (Broca’s area) can only be found on one side of the brain while others (vision) can be found on both
Evaluate hemispheric lateralisation
+ even in connected brains the two sides work differently
> in a PET scan, when participents looked at a whole image, the right hemisphere dominated while if they looked at smaller details, the left halve dominated
- Nielson et al analysed 1000 brain scans of people aged 7-29 an found no evidence of a dominant side
what is Sperry’s split brain research?
Procedure
11 split brain participants were studdied using a set up where an image could be projected into one FV and a different image in the other.
Findings
When an image was shown to the RVF they could describe what they saw
When an image was shown to the LVF they could not describe what they saw but could point to a related image and have an emotional reaction despite reporting having seen nothing
Evaluate Sperry’s split brain research
+ research support
Gazzaniga et al showed split brain participants perform better in certain tasks e.g. identifying an odd object out
- not generalisable
epilepsy is a confounding variable
What is brain placticity?
The brains tendency to change and adapt as a result of experiece through synaptic pruning
What research is into placiticity
Maguire et al studied london taxi drivers brains and found a higher volume of grey matter in their posterior hippocampus than a control group showing their brains had been changed due to experience
Similar findings by Draganski et al who studied medical students brains 3 months before and after exams
evaluate placticity
- it may have negetive behavioural consequences
> makes long term drug use, dementia and phantom limb syndrome more likley
+ life long
Bessola at al found after 40 hrs of golf training participants age 40-60, their motor cortex activity was reduced suggesting more efficient pathways
What is functional recovery after trauma?
A form of placiticity allowing the brain to recover after trauma by passing functions off to other areas
Axonal sprouting: growth of new nerve endings connecting to other nerve cells to form new neural pathways
Denervation supersensitivity: axons that do a similar job do so at a higher level to compensate. can lead to over sensitivity
Recruitment of homologou areas on the opposite side of the brain: spesific tasks can stil be proformed just controlled by a different area until the damaged area is repaired
evaluate functional recovery after trauma
+ real world application
> understanding placitity helps new therapies develop
- cognitive reserve
> research suggests there is a greater chance of disability free recovery for those in education for more than 16 years.
What are the ways of studing the brain?
fMRI: detects change in the flow of oxygen showing where the brain is more active
EEG: measure electrical activity in the brain with electrodes attatched to a skull cap
ERG: uses statistic averaging to filter out unrelated data from EEGs for more spesific data
Post mortem: Examining damaged areas of a brain after death compared to a neurotypical brain
Evaluate the ways of studing the brain
fMRI
+ does not rely on radiation
+ high res pictures
- expensive
- poor temporal resolution
EEG
+ use in longitudinal studies
+high temporal resolution
- very general data
ERG
same as EEG
+ more spesific data
- lack of standadisation
- removing ‘background noise’ is not always possible
Post mortem
+ foundation of early understanding of the brain
- confounding variables
- lack of consent
What are biological rhythms?
exert influence on how body systems behave
governed by internal biological clock (endogenous pacemakers) and changes in the environment (exogenous zeitgebers)
