Neurons, neurotransmitters, drugs and mental function Flashcards
The movement of what ion causes depolarisation?
Na+
Explain the effects of a graded potential
The change in membrane potential is proportional to the electrical input.
i.e. Small input = small change in membrane potential, large input = large change
What is temporal summation, and what is the effect?
2 inputs that arrive together close enough in time causes summation effect = graded potential larger
What is spacial summation?
Arriving from 2 different places at the same time + summate when they meet (where branches come together)
True or false: Graded potentials have to be of a certain size to create electrical event in axon
Yes - this is an AP
What is an AP dependent on?
Whether or not the input reaches threshold
How does the toxin Tetrodotoxin (TTX) work?
Works by blocking ion flow through the channels that generates action potentials
What is a synapse?
the special junctions across which neurons communicate with each other
What is an agonist drug?
increases the activity of a neurotransmitter
What is an antagonist drug?
inhibits/decreases the action of a neurotransmitter
What is the purpose of reuptake?
To give a brief pulse of info, so other states can be signaled
Name 5 ways drugs can have affect on neurotransmission by altering the neurotransmitter.
Synthesis, storage, release, binding, and reuptake
Give a general example of how drugs affecting the SYNTHESIS of neurotransmitter may decrease the PSP
reduction of neurotransmitter synthesised = less to be transmitted each time action potential sent
Give a general example of how drugs affecting the STORAGE of neurotransmitter may decrease the PSP
leaky vesicle = less neurotransmitter across cleft = weaker message
Give a general example of how drugs affecting the RELEASE of neurotransmitter may decrease the PSP
drugs can decrease the amount of neurotransmitter released and therefore the strength of the PSP
Give a general example of how drugs affecting the BINDING of neurotransmitter may decrease the PSP
drugs can can block receptors = less graded potential in post cell
Give a general example of how drugs affecting the REUPTAKE of neurotransmitter may INCREASE the PSP
if reuptake process inhibited, neurotransmitter molecules remain in cleft area for longer = stronger message.
Name 2 agonists at the cholinergic synapse, and their effects on the body
Nicotine - high dose leads to tremors
Black Widow spider venom - causes all muscles start contracting, large enough dose = paralysis, death
Name 2 antagonists at the cholinergic synapse, and their effects on the body
Scopolamine (for seasickness) - suppresses signal from vestibular system Botulinum toxin (food poisoning) - prevents transmission at neuromuscular junction = flaccid paralysis
Name 4 symptoms of Parkinsons disease
tremor, muscular rigidity, slow movements, postural instability
What is a new treatment that helps treat parkinsons, and how does it work?
deep brain stimulation (DBS) - Pulse generator inside brain stimulates neurons, causing them to fire
Name 3 positive symptoms of Schizophrenia
Note: positive symptoms = outside of normal range
Delusions
Hallucination
Disorganized thinking
Name 3 negative symptoms of Schizophrenia
Note: negative symptoms = loss of normal function
○ Decreased emotional responses
○ Hard to generate new ideas
○ Don’t care about what other people think of them, social norms
Name 3 cognitive symptoms of Schizophrenia
Note: cognitive symptoms = changes in cognitive function
Poor working memory
Disruption in executive function, attention span
