B6 - Brain & Mind Flashcards
What are the two communication systems?
The nervous and the hormone (or endocrine) systems
Describe the nervous system (impulses and organs) (2)
The nervous system sends quick short electrical impulses using neurones and contains specialised organs called the brain and spinal cord
Describe the Hormone system (impulses and organs) (3)
The hormone or endocrine system produces slow and long lasting chemical messages in the form of hormones which is produced in glands
What are the two parts of the nervous system?
The Central Nervous system and the Peripheral Nervous system
What is the CNS made up of? (2)
The central nervous system consists of the brain and spinal cord
What is the PNS made up of?
The neurones which connect the CNS to the rest of the body
What are the two types of neurone?
Sensory neurones and Motor neurones
What do sensory neurones do?
Connect receptors with the CNS
What do motor neurones do?
Connect the CNS with effectors
Give an example of a hormone and where it’s produced, its target organ/s and function:
Insulin is produced in the pancreas and acts on muscles, the liver and body cells to take up glucose from the blood
What is a nerve?
A group of neurones
What are the parts of a neurone? (6)
Cell body, nucleus, cytoplasm, dendrites, axon, myelin sheath
The speed of a nerve impulse depends on what three things and why?
Temperature: the hotter the faster
Axon diameter: the wider the faster
Myelin sheath: it allows the impulse to jump between the gaps along the sheath and travel quickly
What are Synapses?
Gaps between one neurone and the next
What happens at a synapse? (5)
- An electrical Impulse travels along an axon
- This triggers the nerve ending to release neurotransmitters
- These chemicals diffuse across the synapse and bind with receptor molecules on the membrane of the next neurone
- The receptor molecules only bind to the specific neurotransmitters they are associated with. This stimulate the second neurone to transmit the impulse
- After the impulse is transmitted, the transmitter is removed (either taken up or broken down) from the synapse
What are the two types of neurotransmitter and what do they do?
Excitory: Stimulate the brain
Inhibitory: Calm the brain and create balanced mood
What is serotonin? (Type of neurotransmitter, job, what can deplete it, how can low levels affect you?)
Serotonin: Inhibitory neurotransmitter
It balances mood, regulates cravings, sleep cycle, pain control and digestion
It can be depleted by regular usage of caffeine or stimulant medication
Low levels produce decreased immune function, anxiety, paranoia and depression
What is dopamine? (Type of neurotransmitter, job, what can deplete it)
Dopamine: an excitory and inhibitory neurotransmitter
It helps with depression, focus and motivation
ADD/ADHD medication and caffeine can cause depletion in excess
Reflex
Simple response to a stimulus
Reflex arc
The pathway of a reflex action
What is the pathway of a reflex? (7)
Stimulus, receptor, sensory neurone, CNS relay neurone, motor neurone, effector, response
What are the four newborn reflexes?
Stepping, breathing, sucking and grasping
What are some reflexes? (3)
dropping a hot object, the knee jerk, the pupil reflex
What do relay neurones do when -a reflex occurs?
They connect with other neurones so we know what happened after a reflex occurred or can override and action
Instinctive behaviour
Behaviour controlled by reflex responses
What are simple organisms?
Organisms that have simple nervous systems and cannot learn behaviour
Conditioning
Learning a reflex response by introducing an unrelated stimulus in association with the first
Describe Pavlov’s Experiment with dogs
Dogs salivate in response to the smell, sight and taste of food
Pavlov rang a bell immediately before giving the dogs food
He repeated the process and soon, the dogs would salivate at the sound of the bell even if not given food; they learnt to associate the bell with food
Associative learning
When the primary and secondary’s stimulus have no direct connection
Explain the experiment by John B. Watson:
John B. Watson experimented on 8 month old Albert who showed I fear towards rats
He scared with loud noises Albert making him cry every time he was shown a rat
Eventually Albert began to associate the rat with fear even once the loud noise was removed after repeatedly scaring him
What are the three main parts of the brain?
The cerebral cortex, the cerebellum and the medulla
What is the cerebral cortex? (5)
The thin folded outer layer of the brain which is in charge of intelligence, memory, language and consciousness
What is the cerebellum in charge of? (2)
Posture and movement
What is the medulla in charge of? (2)
Breathing and heart rate
What are two invasive methods of mapping regions of the brain?
Studying how a person is affected when a certain part of the brain is damaged
During brain surgery, using electrodes to stimulate parts of the brain electrically and seeing how patients are affected
What is a non-invasive method of mapping regions of the brain?
Producing images and mapping activity with scanning methods like MRI
What does MRI stand for?
Magnetic resonance imaging
Neuron pathway
A link between neurones
Feral children
Children isolated from humanity at a very young age that develop weak language skills when reintroduced to civilisation
Memory
The storage and retrieval of information
What are the three types of memory
Sensory, short term and long term memory
You’re more likely to remember information if: (3)
There is a pattern to it
Repetition is used, especially over a long period of time
There is a strong stimulus associated with it
In the multi store model, how long does each type of memory last for?
Sensory: 1-3 seconds
Short term: 15-30 seconds
Long term: 1 second to a lifetime
Why are models limited when explaining memory? (4)
Memory is more complicated than models show
No models exactly explain how long-term memory works
The multi story model is to linear and don’t provide subdivisions or short and long term memory
The model doesn’t differentiate between different types of stimulus and the difference in performance of individuals
What does Prozac do?
Slows down the reabsorption of serotonin so feelings of well-being are prolonged
Depressants
Chemicals that slow down or reduce the rate of something. They block and/ or slow nerve transmissions
Stimulants
Chemicals that speed up or increase the rate of something
Beta blockers
Prescription drugs that block that transmitter adrenaline and reduce heart rate. They are used to treat anxiety and heart rhythm conditions
What does cocaine do?
It blocks the removal of dopamine from the synapse and results in the accumulation of dopamine and an amplified signal to the neurones
What does ecstasy do?
Works on serotonin, after a nerve impulse is transmitted, the transmitter molecules should be removed from the synapse. MDMA blocks the sites on the neurones where serotonin is reabsorbed but after taking it, the serotonin is depleted
Why do multicellular organisms need communication systems?
So that they work as a whole and not as individual cells or organs
