Biopsychology Flashcards
What is the primary means of communication in the nervous system?
Neurons
What do dendrites do?
carry nerve impulses towards the cell body
What does the axon do?
carriers nerve impulses away from the cell body
What is the myelin sheath?
insulating layer on axon that speeds up electrical transmission
What are the nodes of ranvier?
gaps in myelin sheath that speed up electrical transmission
What is the axon terminal?
End of the axon that send impulses to the next neuron across the synapse
How do neurons pass a message?
When at rest there is a negative charge outside the cell and a positive charge inside the cell
When the cell fires, a chemcal process reverses the cahrge and an action potential occurs. An electrical impulse moves down the neuron along the axon
What are the 3 types of neuron?
Sensory, motor and interneuron
What does the sensory neuron do?
carries info from sense to CNS
What does the motor neuron do?
carries info away from CNS to muscles or glands
What do interneurons do?
connect neurons
What is the synapse?
A specialised gap between the end of one neuron and the dendrites of the next
How are signals transmitted to adjacent neurons?
Using neurotransmitters in synaptic transmission
What are neurotransmitters?
Brain chemicals that affect cognitive processes and behvaiour
Name one neurotransmitter and its role
Dopamine, involved in emotional arousal, pleasure and voluntary movement. too much is thought to be responsible for schizophrenia
What happens in an excitatiry synapse?
neurotransmitter makes recieving neuron more likely to fire and pass onb electrical impulse
What happens in an in an inhibitory synapse?
neurotransmitter makes receiving neuron less likely to fire and pass on electrical impulse.
Describe the process of synaptic transmission.
- nerve impulse travels down terminal and arrives at pre-synaptic terminal
- vesicles release their neurotransmitter across the synapse
- the chemical binds to receptor sites on adjacent neuron
- enzymes released to break down excess neurotransmitter or they are reabsorbed by the synaptic terminal
- Vesicles are replenished with neurotransmitter
What two sections is the nervous system divided into?
Peripheral nervous system and CNS
What makes up the CNS?
brain and spinal cord
What is the peripheral NS divided into?
Somatic and Autonomic NS
What is the autonomic NS divided into?
Sympathetic and parasympathetic NS
What is the function of the somatic NS?
responsible for voluntary and reflex actions as messages are transmitted from CNS to muscles and vice versa
What is the function of the autonomic NS?
links internal organs to CNS to control basic functions
it cannot be voluntarily controlled
What is localisation of function?
The idea that different parts of the brain perform different tasks (cortical specialisation) and are involved with different parts of the body
Where is the motor centre located, what is its function and what is the impact of damage?
Frontal lobe, control voluntary movement, impaired movement
Where is the somato sensory centre located, what is its function and what is the impact of damage?
parietal lobe, responds to touch/sensations (cold, pain), lack of skin sensation
Where is the visual centre located, what is its function and what is the impact of damage?
occipital lobe, vision and perception, partial or total blindness
Where is the auditory centre located, what is its function and what is the impact of damage?
LEFT temporal lobe, processes sound, partial or total deafness
Where is the speech production centre located, what is its function and what is the impact of damage?
LEFT frontal lobe (BROCA’S AREA), converts throughts into words, Broca’s Aphasia slow speech that lacks fluency
Where is the speech comprehension centre located, what is its function and what is the impact of damage?
LEFT temporal lobe (WERNICKE’S AREA), understanding of spoken words, Wernicke’s Aphasia difficulty understanding what other’s say
(Evaluation) Describe a study which demonstrates that blood flows to concentrated areas of the brain when certain tasks are performed.
Peterson
Aim- to demonstrate different levels of activity in the brain resulting from different language tasks
Method- Scanner measured brain activity. Ps asked to
a) listen passively to list of nouns
b) think of verbs to attach the a noun
c) silently read a list of nouns
Results- Different parts of the brain were activated during different tasks
a) wernicke’s area
b) Broca’s area and other parts
c) Broca’s area
(Evaluation) Why is the use of psychosurgery to treat serious mental illness a strength?
Specific parts of the brain are destroyed supporting the idea that different parts of the brain have different functions
(Evaluation) Why is holistic functioning a weaknes in cortical specialisation?
suggests most functions involve interconnected areas of the brain
(Evaluation) Why is brain plasticty a weakness in cortical specialisation?
People who have damage to a specific area often recover functioning as another part of the brain takes over
What are the two types of method involved in identifying cortical specialisation?
Invasive and non-invasive methods
What is an invasive method and an example?
A procedure that requires an incision into the body
post mortems
How do post mortems provide a greater understanding of unusual cases?
Investigation into a patient called Tan revealed a lesion in the left hemisphere which was correlated to his speech problem which was broca’s aphasia
Damage found can be correlated to abnormalities in life
What is a non-invasive method and 2 examples?
a procdure that does not require an incision into the body
EEG (cerebro) and PET Scans
How do EEGs work?
Electrodes are placed on the scalp and a measurement of electrical activity is taken. There are two types of wave pattern; rhythmic and arrhythmic
What are (2) strengths and weakness of this method?
+ Not painful/stressful and gives a natural measurement of brain activity as the brain is working in real life
+Can be used to diagnose sleep disorders
- Crude measure, non specific as it measure millions of neurons
How do PET Scans work?
Radioactive glucose injected into the bloodstream
Emission is then measure from different parts of the brain
Higher emission indicates a larger flow of blood to that area of the brain
What are the (1) strenghts and (3) weaknesses of this method?
+ allow us to determine which parts of the brain are active during certain tasks
- issues with informed consent due to radioactive chemical
- expensive method
- Results difficult to interpret as other areas of the brain may also be active
What is a fight or flight response?
The body reacts to a stressor in a stressful situation by preparing it to attack or flee
What does the sympathetic system do?
generally increases bodily functions
responsible for fight or flight
What does the parasympathetic nervous system do?
Generally decreases bodily functions and acts as a brake on the sympathetic nervous system
responsible for rest or digest as it supports normal body activity
What are some examples of the sympathetic nervous system preparing the body for fight or flight?
dilates pupils, inhibits saliva production, increases heart rate, dilates bronchi, increases sweat production
(parasympathetic does the opposite of these
What do the adrenal glands operate in parallel to?
The sympathetic nervous system in a stressful situation
Which system are the adrenal glands part of?
endocrine
How is adrenaline released during a stressful situation?
pituitary gland instructs adrenal glands to release adrenaline into the bloodstream
It increases heart rate and constricts blood vessels in the stomach to inhibit digestion
