Synaptic Plasticity Flashcards
synaptic plasticity
the ability of synaptic connections to change (strengthening, formation or weakening) over time in response to activity or experience
what does synaptic plasticity allow for
neural synapses to physically change, it is the fundamental mechanism for memory formation that leads to learning
neural pathways that are formed during learning are called
memory traces, with each memory trace representing a different memeory
what are the two forms of synaptic plasticity
long-term potentiation and long-term depression
long term potentiation
the long-lasting and experience dependent strengthening of synaptic connections that are reguraly activated at high intensity stimulation
LTP occurs in response to…
frequent and repeated use during learning and memory. where neurotransmitters are repeatedly released into the syanptic gap by the axon terminals of the presynaptic neuron and recieved by receptor sites on the dendrites of the post-synaptic neuron
what occurs during memory and learning
where neurotransmitters are repeatedly released into the syanptic gap by the axon terminals of the presynaptic neuron and recieved by receptor sites on the dendrites of the post-synaptic neuron
what does the increased strength of synaptic connections in the neural pathway in LTP do
it makes the postsynaptic neurons more receptive to neural signals from the presynaptic neuron and consequently more readily activated. This increases the efficiency of synaptic transmission along the neural pathway, so that if this pathway is actiavted again, neural signals are transmitted more rapidly and efficiently
what causes the structural changes in LTP
a result of the increased release of neurotransmitters, specifically glutamate
what are the structural changes if LTP
- increased number of receptor sites on the dendrites of the post-synaptic neuron
- dendritic branching: bushier dendrites on the post synaptic neuron due to sprouting
- increased number of synaptic connections between neurons due to sprouting
- growth filigree appendages
growth filigree appendages
new sprouts from axon terminals
long term depression
the long-lasting and experience dependent weakening of synaptic connections between neurons that are not regularly coactiavted (low intensity stimulation)
LTD occurs in response to
if a neural pathway that has been previously established during learning and memory is no longer reguraly activated, this neural pathway is no longer necessary
what causes LTD
when there is infrequent release of neurotransmitters into the synaptic gap by the axon terminals of the presyanptic neuron
what does the infrequent release of neurotransmitters cause
it makes the most synaptic neuron less recptive to neural signals from the pre-synaptic neuron and consequently less readily actiavted. this decreases the efficiency of synaptic transmission along the neural pathway
