Biopsychology Flashcards
What is the nervous system split up into?
- central nervous system
- peripheral nervous system
What is the human nervous system?
A body wide system of nerve cells that collects and processes information and then directs organs and muscles via electro chemical messages
What is the function of the CNS and what 2 parts of the body do they contain?
- complex processing
- the brain (all conscious and most unconscious processing)
- the spinal cord (receives and transmits information, also is responsible for some simple reflexes)
What is the peripheral nervous system?
A body wide network of messenger neurons. Sensory neurons deliver information to the CNS and motor neurons transmit information away from the CNS
What is the PNS split into and what are they?
- somatic nervous system (controls skeletal muscles and is a voluntary system)
- autonomic nervous system (controls actions of internal organs and glands and is an involuntary system)
What does the sympathetic branch (ANS) do?
Increases bodily activities and releases noradrenaline in a stress response (fight or flight)
-heart rate increase
-sweat increase
-breathing rate increase
-dilates pupils
-inhibits digestion
What does the parasympathetic branch do?
Decreases bodily activities and releases acetylcholine. Activates in rest (rest and digest)
-heart rate decrease
-sweat decrease
-breathing rate decrease
-constricts pupils
-stimulates digestion
What is the motor cortex responsible for?
Responsible for voluntary motor movements
Where is the motor cortex found?
Found in BOTH frontal lobes of the brain
What is the function of the somatic nervous system?
Transmits information from receptor cells to the CNS
Also receives information from the CNS that directs muscles on how to act
What is the function of the autonomic nervous system?
Responsible for unconscious bodily functions
What is the autonomic nervous system split into?
The parasympathetic nervous system / the sympathetic nervous system
What is the function of the sympathetic nervous system?
Co-ordinates organs when in situations when the individual needs to be aroused / when our muscles need oxygen
Signals to our hearts,lungs and liver when to work harder
What is the function of the parasympathetic nervous system?
Co-ordinates to our organs when we can relax and conserve energy
Rest + digest
What happens to the eye, heart and saliva glands in the SNS
Pupil dilates
Heart rate increases
Inhibited saliva production
What happens to the eye, heart and saliva glands in the PSNS?
Constricts pupil
Heart rate decreases
Stimulated saliva production
What are the 6 parts of a neuron?
- Cell body / soma
- Nucleus
- Dendrites
- Axon
- Myelin sheeth
- Axon terminal
What is the function of the soma?
Control centre of the neuron and includes the nucleus
What is the function of the nucleus?
Contains genetic material of the cell
What is the function of the dendrites in a neuron?
Dendrites recieve signals from other neurons or from sensory receptor cells. Typically connected to cell body
What is the function of the axon in a neuron?
Long slender fibre that carries nerve impulses in the form of an electrical impulse, action potential.
What is the function of the myelin sheath in the neuron?
Insulates axon so impulses travel faster and preserves the signal
What is the function of the axon terminal in a neuron?
Connects the neuron to other neurons using a process called synaptic transmission
What is unique about a relay neuron?
A relay neuron has no myelin sheath
What is unique about a sensory neuron?
In a sensory neuron the cell body sticks out
What is the function of a sensory neuron?
Sensory neurons transmit nerve impulses from sensory receptors to the brain and spinal cord
Impulses begin as sensory receptors and are translated into sensations at the brain which allows for reflex actions
What is the function of a motor neuron?
Carry impulses from the CNS to other areas of the body
Releases neurotransmitters which bind to muscle receptors and trigger muscles movement
Muscle relaxation is caused by the inhibition of the motor neuron
What is the function of a relay neuron?
Connect sensory and motor neurons allowing for communication
Located in brain and spinal cord
What neurons are uni/multipolar?
Unipolar- sensory neurons
Multipolar- motor and relay neurons
What was the aim of Sperry and Gazzanigas study?
To investigate the effects of hemispheric reconnection and to show that each hemisphere has different functions
What was the method of sperrys split brain study?
Comparing performance of 11 split brain patients, who had undergone surgery for their epilepsy to people with no connection
In lab conditions, participants were asked to fixate on a dot in centre of screen while a word or picture was flashed to the left or right visual field for 1/10 of a second
They would then make responses verbally or using left/right hand without being able to see their hands
What were the results of the split brain study?
- When object was shown to right visual field the patient could easily say what was seen but if object was shown to left visual field they reported nothing was there - although could identify object from a grab bag using their left hand
- If two words were simultaneously on their side of the visual field the patient would write the word on the left with their left hand and say the word on the right
- When asked to match a face from a series of faces, picture processed from right hemisphere was consistently selected whereas left hemisphere was consistently igored
What are the evaluation points of split brain research? AO3
+ quasi experiment / high control
+ pioneering research
- population validity
- individual differences - lateralisation not fixed
How does split brain research have high control? AO3
P: Sperry and Gazzanigas research is a quasi experiment we they were able to take advantage of the naturally occurring variable as the epileptic patients had experienced hemisphere deconnection
E: able to have high control over the experimental environment and so demonstrate the effect that hemisphere disconnection has on brain function
E: since hemisphere deconnection was regarded as the only significant difference between the two groups, the observed difference in performance was seen as having been caused by this deconnection so providing support for the theory of hemispheric lateralisation
L: consequently it can the argued that this study has high internal validity
How is Sperrys split brain research pioneering research? AO3
P: this research had a huge impact on our understanding of how different hemispheres of the brain work
E: Sperry and Gazzanigas work into split brain has produced an impressive sizeable body of research that suggests that the left hemisphere of the brain is more analytical and verbal and the right is more adept to spatial tasks and music
E: this is a strength as the research has enabled scientific progress
How does Sperry and Gazzanigas split brain research have low population validity? AO3
P: research has low population validity
E: sample consists of only 11 split brain patients which is a small sample size which may not be representative. In addition, participants epilepsy may of caused changes in the brain which are not present in the brains of others - another reason why the sample may be unrepresentative
E: consequently, it can be argued that this study lacks external validity
How are individual differences a limitation of Sperrys split brain research? AO3
P: lateralisation appears to change with age and for many types of task
E: patterns in younger individuals tend to switch to bilateral pattern in health older adults. For example, Szaflarski found that language becomes more lateralised in the left hemisphere with increasing age, but after the age of 25 lateralisation decreased with each decade of life. This suggests that older people’s brains recruit both hemisphere to increase their processing power, perhaps to compensate for age related cognitive decline
E: this is a limitation of hemispheric lateralisation theory because these findings suggest that the theory might not be completely correct
What does plasticity refer to?
The brains tendency to change or adapt