More for Exam 1 Flashcards
What is static brain imaging?
create a static image of the brain, which is an anatomical image and not an image of brain activity (MRI, CT, DTI)
What is dynamic brain imaging?
dynamic functional connectivity has shown that brain networks fluctuate on the scale of seconds to minutes (fMRI, PET, EEG)
What occurs when there is a positive current?
makes Vm more negative; hyperpolarization; DF = positive, positive ions flow out of cell
What occurs when there is a negative current?
makes Vm more positive; depolarization; positive ions flow into the cell, DF = negative
What are asymmetric synapses?
usually excitatory (glutamatergic) and where postsynaptic density (PSD) that is thicker than the presynaptic fraction
What are symmetric synapses?
usually inhibitory (GABA), typically near soma and axon hillock
How do you calculate the PSP distance along the dendrite?
Vx = Vo/(ex/lambda)
What is temporal summation?
PSPs from same synapse occurring rapidly after each other
What is spatial summation?
PSPs from different synapses across cell at same time
How does the length constant change when the membrane resistance is higher?
the electrical signal experiences less resistance to its spread along the neuron’s membrane, allowing it to propagate over a longer distance
How does the length constant change when the intracellular resistance?
it hinders the spread of electrical signals along the neuron’s membrane, resulting in a reduced length constant
What is unique about excitable dendrites?
help propagate EPSPs toward soma & initiation zone and can allow for Backpropagating AP to travel back from axon through dendrite
What are the effects of mutations in sodium channels?
can lead to increased neuronal excitability, making individuals more prone to seizures.
What are the effects of mutations in potassium channels?
Mutations in potassium channel genes can disrupt the resting membrane potential of neurons and regulating their excitability
What are the effects of mutations in calcium channels?
Mutations in channel subunits can lead to abnormalities in calcium ion influx leading to increased neurotransmitter release
How do antiporters work?
active transporters because they move substrates against their concentration gradients, from areas of lower concentration to areas of higher concentration
How do symporters work?
The molecule or ion is transported along its concentration gradient, and this movement provides the energy needed to move the other substrates against their concentration gradients.
What is an example of an ATPase pump
sodium potassium pump
What is a pore loop?
short polypeptide segments that form ion channel selectivity filter for amino acids and size
What is an Ach Transporter?
H+ antiporter that loads acetylcholine
What is Acetylcholinesterase?
Acetic acid and choline that breaks down acetylcholine
How can we tell what type of channel is present in the membrane patch?
Change the concentration of ions
What are thermosensitive ion channels?
Trp channels that measure heat and pain
What are mechanosensitive ion channels?
Trp and Peizo channels which are stretch receptors, tactile receptors (touch), auditory hair cells
