Biopsych Flashcards
What is the nervous system
A specialised network of cells in the human body, and our primary internal communication system.
What are the two main functions of the nervous system
Collect, process and respond to information in the environment
Co-ordinate workings of different organs and cells in the body
What are the two subsystems of the nervous system
Central nervous system
Peripheral nervous system
What is the CNS made up of
The brain and spinal cord
What is PNS made up of
Autonomic nervous system
Somatic nervous system
What does the autonomic nervous system do
Govern vital functions in the body like breathing, digestion and stress responses
Contains sympathetic and parasympathetic nervous systems
Involuntary system
What does the somatic nervous system do
Controls skeletal muscles
Is voluntary
What do the sympathetic and parasympathetic nervous systems do
Sympathetic nervous system prepares the body for emergencies, and slows non-essential functions like digestion.
Parasympathetic nervous system reverses these changes once threat has passed
How does the sympathetic nervous prepare a body for emergencies
Increases heart rate
Dilation of pupils
Sweating
Relax bladder
What does the somatic nervous system do
Governs muscle movement and receives information from sensory receptors
What is the endocrine system
Instructs glands to release hormones directly into the bloodstream, which are carried towards target organs
Give an example of a hormone and its use
Thyroxine, released from thyroid gland, increases heart rate and metabolic rate, affecting growth rates.
What is the pituitary gland
“Master gland” controls release of hormones from all the other endocrine glands
Describe the process of entering fight or flight
Part of the brain called hypothalamus activates pituitary gland, triggering the sympathetic nervous system. Adrenaline releases from adrenal gland, causing physiological changes of increased breathing and heart rate and relaxing bladder. Once threat has passed, parasympathetic nervous system reverses the changes.
What is a neuron
Building blocks of central nervous system. Nerve cells that process and transmit messages through chemical and electrical signals.
What are the three types of neuron and their functions
Sensory neuron - carry messages from PNS to CNS.
Long dendrites and short axons.
Relay neuron - Connect sensory neurons to motor neurons.
Short dendrites and long axons.
Motor neuron - Connect CNS to effectors like muscles and glands.
Short dendrites and long axons
What are the parts of a neuron
Cell body (contains nucleus)
Dendrites (extend from cell body carrying nerve impulses)
Axon (carries impulses away from cell)
Myelin sheath (fatty layer protecting axon)
What is synaptic transmission
Process by which neighbouring neurons communicate with each other by sending chemical messages across the gap (synapse) that separates them.
How are signals transmitted in a neuron vs between them
Within the neuron = electrically
Between neurons = chemically
What are neurotransmitters
Chemicals that diffuse across a synapse to the next neuron in a chain.
What happens when a neurotransmitter crosses the synapse
Picked up by a postsynaptic receptor site on dendrites of next neuron. Chemical message is converted to an electrical signal, where it is taken along the axon to the synapse where the process repeats.
What are the two effects neurotransmitters can have
Excitatory - increases positive charge of post-synaptic neuron, increasing chance that the neuron will pass on electric signal
Inhibitory - increases the negative charge of the postsynaptic neuron, decreasing chance of electric signal passing on
What is the localisation theory
That different parts of the brain carry out different functions
What and where is the motor area
Region in the frontal lobe involved in regulating movement
What and where is the somatosensory area
Area in the parietal lobe that processes sensory information like touch
What and where is the visual area
Part of occipital lobe that receives and processes visual information
What and where is the auditory area
Located in temporal lobe and concerned with analysis of speech based information
What and where is Broca’s area
Area of frontal lobe in LEFT hemisphere responsible for speech production
What and where is Wernicke’s area
Area of the temporal lobe in LEFT hemisphere responsible for language comprehension
What are three strengths of localisation theory
Neurosurgery
Brain scans
Phineas Gage
How does neurosurgery support localisation theory
Neurosurgery is used as a last resort in treating some mental illnesses, by targeting regions of the brain associated with the illness’ behaviours.
Dougherty et al (2006) reported on 44 people with OCD who had undergone neurosurgery, and 30% had a successful response, and another 14% had a a partial response. This suggests that behaviours associated with these illnesses may be localised.
How do brain scans support localisation theory
Petersen et al used brain scans to demonstrate how Wernicke’s area was active during a listening task, and Broca’s area active during a reading task.
Who was Phineas Gage and how did he support localisation
In 1848, Phineas Gage was in an accident and an iron bar went through his head, removing most of his left frontal lobe. He survived, but went from being a calm and reserved person to quick tempered and aggressive. This suggests that mood regulation is localised to the left frontal lobe.
What are two challenges to the localisation theory
Lashley (1950)
Dick and Tremblay (2016)
How did Lashley’s experiment weaken localisation, and what was the experiment
Removed 10-50% of different areas of the cortex of rats learning a maze. No area was proven to be more important than any other in terms of the rats’ ability to learn the route. Learning appeared to use every part of the cortex rather than one specific area, suggesting higher cognitive processes like learning were more holistic.
Who was Phineas Gage and how did he support localisation
In 1848, Phineas Gage was in an accident and an iron bar went through his head, removing most of his left frontal lobe. He survived, but went from being a calm and reserved person to quick tempered and aggressive. This suggests that mood regulation is localised to the left frontal lobe.
What did Dick and Tremblay do and how does it weaken localisation
Found only 2% of researches believe language is localised to Broca’s and Wernicke’s areas. fMRIs found that language in the brain is distributed holistically and that “language streams” have been identified across the cortex.
What is plasticity
The brains ability to adapt and change due to environment, e.g damage or learning new skills
What is functional recovery
Brains ability to move functions from damaged areas of the brain to other undamaged areas
What is synaptic pruning
Synapses that are frequently used get stronger over time, while unused synapses are lost, to increase the brain communication efficiency
What did Boyke et al find (2008)
Found evidence for plasticity in the brain
Taught 60 year olds a new skill (juggling).
Found increased grey matter in the visual cortex, but these changes reversed when the Ps stopped practising
What is grey matter
Contains most of the brains neuronal cell bodies. The grey matter includes regions of the brain involved in muscle control and sensory perception like seeing hearing and memory making.
What is neural unmasking
Part of functional recovery
Some synaptic connections are physically intact but ‘dormant’.
Normally input rate too low to activate them, but if input rises, for example surrounding area gets damaged, then these neural connections would be unmasked.
What is Maguire’s study (name, process and findings)
Taxi driver study
MRI of 16 male taxi drivers compared to MRI of 16 non taxi drivers (matched on age/gender).
Posterior hippocampi in taxi drivers significantly larger than controls, suggesting physical brain structure is plastic and adaptable.
Research support of plasticity
What are two strengths of plasticity
RWA for rehabilitative therapy - stopping patients from using coping methods like body language can help them improve via functional reorganisation
Maguire taxi driver study - research support
What 3 ways can stem cells help recovery
Implanted stem cells could be used to replace dead or dying cells
Transplanted stem cells could secrete growth factors that rescue the injured cells
Transplanted stem cells could form a neural network that links an uninjured brain site (where new stem cells are made) with the damaged region of the brain.
What does contralateral mean
Each hemisphere of the brain controls the opposite side of the body.
What is the function of a motor cortex
Voluntary muscle movements across the body
What can happen if motor cortex is damaged
Loss of muscle function
Paralysis in severe cases
What does the somatosensory cortex do
Receive info from the senses
What happen if somatosensory cortex is damaged
Loss of sensation in opposite side of body to damage
What is the auditory cortex
Receive sound information from ears
Where is the visual cortex
Occipital lobe
What does visual cortex do
Take in visual information from eyes from opposite visual field
Outline Sperrys split brain research
Quasi-experiment with 11 patients that underwent corpus callosotomy
Projected info to each visual field so that info to each hemisphere was controlled.
Participants told to either say or draw what they had seen
What were the results of Sperrys split brain research
Picture presented to right visual field (processed by left hemisphere) could be described. Left visual field was not as clear or could not see anything.
Picture presented to left visual field (processed by right hemisphere) could be drawn well and clearly, while right visual field had poor drawing.
What does Sperrys study suggest
Both hemispheres can act independently
Language centres in left side of brain
Who conducted split brain research and when
Sperry (1968)
Gazzanigas (1983)
How did Gazzanigas conduct split brain research
Corpus callosotomy patients
Presented each hemisphere of the brain with faces
The right hemisphere was much better at recognising the faces, suggesting facial recognition is specialised in right hemisphere
Evaluate split brain research - limitations
Small samples of varying degrees of surgical alteration - varying amounts of connection cut and all had undergone drug therapy.
Lacks mundane realism, in real world head will move side to side and use other cues to pass information to both hemisphers. Low validity.
Evaluate split brain research - positive
Fundamantal impact on psychological understanding of consciousness and identity. Suggests brain is a combination of separate intelligent units working together.
What is Maguire’s study (name, process and findings)
Taxi driver study
MRI of 16 male taxi drivers compared to MRI of 16 non taxi drivers (matched on age/gender).
Posterior hippocampi in taxi drivers significantly larger than controls, suggesting physical brain structure is plastic and adaptable.
Research support of plasticity
What is a circadian rhythm
A biological rhythm lasting around 24 hours
What are examples of circadian rhythms
Regulating sleep
Release of hormones
Body temperature
What is an endogenous pacemaker
Internal body clocks that keep biological processes to time
What is an exogenous zeitgeber
External cues that change endogenous pacemakers to match the environment
What is the suprachiasmatic nucleus
The EP for sleep wake cycle
What did Siffre do to support circadian rhythms
Lived in a cave for 6 months with no natural light or other potential exogenous zeitgebers. Siffres body clock maintained a regular cycle of around 25 hours.
However, was criticised for having artificial lights which could have disrupted the circadian rhythm
What did Vetter do to support circadian rhythms
Found 27 office workers who were exposed to strong blue light shifted the timing of their circadian rhythms to match the office lighting, suggesting artificial light is a strong EZ for sleep wake cycle.
What are 3 supports for circadian rhythms
Siffres cave study
Vetter blue light office study
RWA - understanding how blue light from devices affects sleep, combat effects of jet lag and shift work.
What is an infradian rhythm
A biological rhythm that takes longer than 24 hours to complete a cycle
What is an example of an infradian rhythm, and what are its endogenous pacemakers
Menstrual cycle
Oestrogen (pre ovulation)
Progesterone (post ovulation)
What did Stern and McClintlock do to support infradian rhythms
20 women given pads from armpits of donor women to wipe on their top lip
Found women would shorten or extend their menstrual cycle to match the donor.
Suggests synchronisation due to pheromones acting as EZs
However, not widely accepted humans can detect pheromones
What is an ultradian rhythm
Takes less than 24 hours to complete
What is an example of ultradian rhythms
Sleep stages
How long is a sleep stage cycle
90 mins
What is the process of one sleep stage cycle
NREM
NREM
NREM
REM
What did Dermot and Kleitman study to support sleep cycle
EEG to record brainwaves of 33 participants during one nights sleep.
Followed a cyclic activation pattern, with NREM being slow-wave and REM during high activation.
What are two benefits to ultradian rhythms
RWA - devices based on sleep improvement founded due to knowledge of sleep stages. Makes a happier and more economically productive society
Dermot and Kleitman sleep study
