Biopsychology Flashcards
What is the central nervous system?
1) brain + spinal cord
2) controls behaviour + regulation of body’s physiological processes
3) receives information from sensory receptors
4) sends messages to muscles + glands
What areas is the brain divided into?
1) cerebrum
2) cerebellum
3) diencephalon
4) brain stem
What is the cerebrum?
1) largest part of the brain
2) 4 lobes
3) split down middle into two halves - hemispheres
What is the cerebellum?
Responsible for motor skill/balance/coordinating muscles to allow precise movement
What is the diencephalon?
Contains the thalamus + hypothalamus
What is the thalamus?
Regulates consciousness/sleep/alertness
What is the hypothalamus?
Regulates body temperature/stress response/hunger + thirst
What is the brain stem?
Regulates breathing + heart rate
What is the function of the spinal cord?
1) relays information between brain + rest of body
2) allows brain to monitor/ regulate bodily processes (digestion + breathing)/coordinate voluntary movement
What is the spinal cord connected to?
1) different parts of the body by pairs of spinal nerves - connected to specific muscles + glands
2) areas connected to spinal cord will be cut off + stop functioning if spinal cord is damaged
What is the peripheral nervous system?
1) nervous system (not brain + spinal cord)
2) transmits messages via neurons to and from central nervous system
3) somatic nervous system/autonomic nervous system
What is the peripheral nervous system divided into?
1) somatic nervous system
2) autonomic nervous system
What is the somatic nervous system?
1) connects senses with central nervous system
2) sensory + motor pathways
3) controls skeletal muscles + movement
4) controlled by motor cortex
5) conscious activities
What is the autonomic nervous system?
1) motor pathways only
2) controls organs + glands
3) controlled by brain stem
4) unconscious nervous system
5) sympathetic nervous system/parasympathetic nervous system
What is the autonomic nervous system divided into?
1) sympathetic nervous system
2) parasympathetic nervous system
What is the sympathetic nervous system?
1) activated when stressed
2) increases heart + breathing rate
3) stops digestion
4) reduces salivation
5) dilates pupils
6) diverts flow of blood from surface of the skin
7) fight or flight response
What is the parasympathetic nervous system?
1) activated when relaxing
2) conserves energy
3) reduces heart + breathing rate
4) starts digestion
5) increases salivation
6) constricts pupils
What is biopsychology?
How biology influences behaviour
What do receptors do?
1) detect stimuli
2) communicate with effectors via nervous/endocrine systems
What do effectors do?
Bring about a response to a stimulus
What are neurons?
1) specialised nerve cells
2) transmit information as electrical impulses around body
What is the cell body?
Control centre of neuron
What is the nucleus?
Contains genetic material
What are dendrites?
Receive information from other neurons
What is the axon?
Carries electrical impulse from cell body to axon terminal
What is the myelin sheath?
Insulating layer that protects axon + speeds up transmission of electrical impulse
What are Schwann cells?
Make up myelin sheath
What are Nodes of Ranvier?
Gaps in myelin sheath that speed up electrical impulse along axon
What are the neurons that are involved in the transfer of information to + from the central nervous system?
1) sensory neuron
2) relay neuron
3) motor neuron
What do sensory neurons do?
1) convert information from sensory receptors into electrical impulses
2) transmit electrical impulses from receptors to central nervous system
3) upon reaching brain, convert electrical impulses into sensations so body can react appropriately
Why do some sensory impulses terminate at the spinal cord?
Allows reflexes to occur quickly without delay of sending impulses to brain
What do relay neurons do?
1) transmit electrical impulses between sensory neurons + motor neurons so they can communicate with one another
2) analyses sensation during reflex arc + decides how to respond without waiting for brain to process that you are experiencing pain
What do motor neurons do?
Send electrical impulses from central nervous system to effectors so they can function
Briefly describe the order of transmission of information to + from the central nervous system.
1) stimulus
2) receptors
3) central nervous system (sensory + relay + motor neurons)
4) effectors
5) response
What are reflexes?
1) fast, automatic responses to certain stimuli
2) bypass conscious brain, go through spinal cord/unconscious part of brain
3) rapidly respond to help avoid damage
What is a synapse?
Junction between neuron + another neuron/neuron +e effector
What is the synaptic cleft?
Tiny gap between pre-synaptic membrane + post-synaptic membrane
What is the presynaptic neuron?
Neuron before the synapse
What is synaptic transmission?
1) when electrical impulses (action potentials) reach pre-synaptic terminal, it triggers release of neurotransmitters from vesicles on pre-synaptic membrane
2) neurotransmitter diffuses across synaptic cleft + binds to specialised receptor sites on post-synaptic membrane
3) neurotransmitters binded to receptors trigger electrical impulse/muscle contraction/cause hormone to be secreted
4) neurotransmitter removed from cleft through re-uptake
What is re-uptake?
Neurotransmitters taken back by vesicles where they are stored for later release
What do psychoactive drugs do?
1) affect transmission of neurotransmitters across synapse
2) increase/inhibit transmission
What do excitatory neurotransmitters do?
1) cause excitatory post-synaptic potential
2) post-synaptic neuron more likely to fire impulse
What do inhibitory neurotransmitters do?
1) cause inhibitory post-synaptic potential
2) post-synaptic neuron less likely to fire impulse
What is summation?
1) determines where post-synaptic neuron will fire an impulse
2) likelihood that post-synaptic neuron will fire determined by adding up excitatory + inhibitory synaptic input
What will happen if there are more inhibitory post-synaptic potentials?
Less likely that post-synaptic neuron will fire impulse
What will happen if there are more excitatory post-synaptic potentials?
More likely that post-synaptic neuron will fire impulse
In what ways can the strength of an excitatory post-synaptic potential be increased?
1) spatial summation
2) temporal summation
What is spatial summation?
Large number of excitatory post-synaptic potentials generated at many different synapses on same post-synaptic neuron at same time
What is temporal summation?
Large number of excitatory post-synaptic potentials generated at same synapse by a series of high-frequency action-potentials by pre-synaptic neuron
How is the rate at which a particular cell fires determined?
1) if excitatory synapses more active, cell fires at higher rate
2) if inhibitory synapses more active, cell fires at lower rate, or not at all
What is a gland?
Group of cells specialised to secrete a useful substance
What is a hormone?
Chemical messenger
When are hormones secreted?
When a gland is stimulated
When are glands simulated?
1) change in concentration of specific substance
2) electrical impulses
Briefly describe the order of events in the endocrine system.
1) stimulus
2) receptors - detect change in environment
3) hormone - released into blood
4) effectors - target cells detect hormone
5) response -
What major glands are involved in the endocrine system?
1) hypothalamus
2) pituitary gland
3) pineal gland
4) thyroid gland
5) parathyroid glands
6) thymus gland
7) adrenal gland
8) pancreas
9) gonads (ovaries + testes)
What does the hypothalamus do?
Produces hormones that control the pituitary gland
What does the pituitary gland do?
Releases hormones to control other glands in the endocrine system
What does the thyroid gland do?
1) produces thyroxine
2) controls body’s metabolic rate/growth/maturation
What do the adrenal glands do?
Produce adrenaline
What does the pancreas do?
Releases insulin + glucagon - regulates blood sugar level
What do gonads (ovaries + testes) do?
Produce sex hormones (oestrogen + testosterone) - reproduction/development of sex organs + secondary sexual characteristics
How is the fight or flight response activated?
1) hypothalamus triggers activity in sympathetic branch of autonomic nervous system
2) stimulates adrenal medulla within adrenal glands - releases adrenaline + noradrenaline into bloodstream
How do adrenaline + noradrenaline affect the body during the fight or flight response?
1) blood pressure + heart rate increase - get blood quickly to areas where needed for activity
2) digestion decreases - so blood can be directed to brain + muscles
3) muscles become more tense - body is more physically responsive
4) perspiration increases - so body can cool down
5) breathing rate increases - more oxygen can be sent to muscles
6) pupil size increases - more light can enter eyes for clearer vision
7) salivation decreases - digestive system isn’t needed
What does the parasympathetic nervous system do after the threat in the fight or flight response has passed?
1) dampens down stress response
2) slows down heartbeat
3) reduces blood pressure
4) restarts digestion
What is a strength of the fight or flight response?
1) makes sense from evolutionary point of view - would have helped individuals survive by fighting/fleeing threat
2) adrenaline is essential in preparing body for stress - people with malfunctioning adrenal glands do not have normal fight or flight response to stress
What is a weakness of the fight or flight response?
1) first reaction to stress is to freeze - stopping/looking/listening/being hyper vigilant to danger
2) females tend + befriend in times of stress - hormone oxytocin means they are more likely to stay + protect offspring
3) some males tend + befriend - males + females tended + befriended during terrorist attacks on September 11th 2001
Why do hormones only affect target cells even though they come into contact with most cells in the body?
Target cells only respond to a particular hormone because they have receptors or that hormone - when enough receptor cells are stimulated by that hormone there is a physiological reaction
What are the divisions of the pituitary gland?
1) anterior pituitary gland
2) prosterior pituitary gland
What does the anterior pituitary gland do?
Prepares body for fight or flight response when stressed
What does the posterior pituitary gland do?
Releases hormone oxytocin - crucial for infant/mother bonding
