Biol 105 Exam 3 Flashcards
synaptic strengthening
increase in the number of receptors or vesicles full of neurotransmitter, greater size of synapse, along with other structural features are all mechanisms for strengthening a synapse
Hebbian Learning
simultaneous activation of cells leads to pronounced increases in synaptic strength between those cells
neurons that fire together wire together
one contributes to the firing of the other -> causation
hebbian learning
neuronal circuits can change over time
- structural ( size of synapse/number of receptor)
- function strength of signal at the synapse)
hebbian learning concept
dendritic spine
a small membranous protrusion from a neurons dendrite that typically receives input from a single synapse of an axon.
concept of a dendritic spine
dendritic spine number is increased in autism, decreased after adolescence in schizophrenia and decreased in late adulthood with Alzheimer’s disease
adaptation
the reduction in firing of a neuron over time despite a constant input
habituation
firing of a neuron decreases over time due to the repetition of an input
facilitation
the increase in firing of a neuron over time in response to constant input
sensitization
the firing of a neurom increases over time due to the repetition of an input
(opposites of adaptation and habituation respectively)
associative learning
when an association between two stimuli or a behavior and a stimulus is learned
senile plaque
extracellular deposits of amyloid beta (Ab) peptides in the gray matter of the brain and are the primary marker of Alzheimer’s disease
GCaMP
GFP that only glows when Calcium goes into the cell
-marks activity
strength of signaling or repeated stimulation leads to
a stronger synapse
Which receptor mediates long term changes at the synapse?
NMDA
Why do 2 inputs active at the same time strengthen both synapses
synapse 1 causes depolarization briefly throughout the neuron so if synapse 2 is active, the NMDAR is activated and the synapse is strengthened
neurofibrillary tangle
intracellular aggregates of hyper phosphorylated tau protein that are most commonly known as a marker of Alzheimer’s Disease.
Lewy body
intracellular aggregates of protein notably a-synuclein that occur in Parkinson’s disease and Lewy body dementia
Amyloid Precursor Protein (APP)
a membrane protein found mainly in neurons that gives rise to the material in amyloid plaques (Ab)
Long Term Depression (LTD)
a persistent weakening of synapses based on recent patterns of activity
NMDA Receptor (NMDAR)
a ligand-dependent AND voltage-sensitive ionotropic glutamate receptor
NMDA RECEPTOR CONCEPT
resting membrane potential (-70mV), effects that neuronal depolarization (less negative/closer to zero) and hyperpolarization (more negative) have in terms of numerical values. Threshold of -55 mV is usually when action potential is triggered
Mcullough Pitts Neuron
inputs nudge neuron towards or away from an action potential
-single input from any one dendrite is enough to trigger AP
Deep Brain Stimulation
implantation of a electrode or device to deliver electrical stimulation to a region effectively inactivating the region effectively inactivating the region
Where will you search for Parkinson’s Disease using Deep Brain Stimulation?
globus palidus and other regions
Where would you search for Multiple sclerosis using deep brain stimulation
thalamus
Computerized Tomography (CT) scan
uses x-rays from many different angles and a computer to build up an image of the brain or body
Hemorrhagic stroke
ruptured blood vessel in the brain
Ischemic stroke
blocked blood vessel in the brain
transient ischemic attack (TIA)
symptoms of a stroke that resolve in 1-24 hours “mini -stroke “
FAST
facial drooping, arm weakness, speech difficulties, time
penetrating arteriole
blood vessel that branches from a surface artery and projects into the brain
- astrocytes make broad contacts with blood vessels
concept on glial cells
respond to neurotransmitters too, leading to uptake of oxygen, water and glucose from an arteriole or capillary
blood brain barrier
combination of endothelial cells and astrocytes acting as a filter allowing only certain substances as a filter allowing only certain substances to pass from the blood into the brain
MRI
massive magnets align water molecules in your body, radio wave pulses used to map structures
fMRI
differentiates between oxygenated and deoxygenated hemoglobin
Voxel
measure of neuron activity in a region
proprioceptive neuron
sensory neurons that measure internal forces such as tension especially in muscles
Kinase
enzyme that phosphorylates other proteins switching them on or off
long term potential (LTP)
a persistent strengthening of synapses based on recent patterns
what allows Ca++ ions into the neuron ONLY if both the glutamate ligand and membrane depolarization are present
NMDAR receptor
which ion blocks the channel when NMDA is inactive
Mg++
ocular dominance
tendency to prefer visual input from one eye or the other
ocular dominance columns
arise as the axons from each eye group together in the visual cortex
critical period
brain is highly responsive to inputs, particularly environmental stimulation
neural plasticity
changes in neural organization which may account for various forms of behavioral modifiability, either short-lasting or enduring, including, maturation, adaptation to a mutable environment, specific and unspecific kinds of learning, and compensatory adjustments in response to functional losses from aging or brain damage.
