Chapter 3 brain substrates (aplasia (look at diagrams) (sensitization (if…
Chapter 3 brain substrates
aplasia (look at diagrams)
Good for studying because
pattern of neurons are hard wired
they only have 20,000 neurons
neurons are large
gill withdrawl effect
touch the tail, siphon and gill, the gill contracts within the mantle, time to relax is measured
if you touch it every minute for so many minutes they retract less and less but it recovers quickly prob cause it is a mass trial
releases less glutamate as it happens, with every presentation, less and less NTs get released. The receptor is getting depressed.
siphon - sensory neuron s - glutamate - motor neuron M - gill muscles
habituation in aplasia
involves only the synapses that were activated during the stimulus does not generalize to other ones.
long term = lasts longer than 10 minutes
exposure is spaced over days
Number of sensory neurons decreases
if you shock instead of touch then it will retract for longer because it has become desensitized
causes release of serotonin from the inter modulatory neuron
hetero-synaptic, involves changes across several synapses
not stimulus specific
input from each sense is relayed to a specialized sensory cortex
each neuron within the specialized cortex has a distinct receptive field
organized in a topographic map, things that do the same thing are organized close to each other
cortical plasticity: change in receptive fields of neurons of the sensory cortex due to development or experience
ex: 2 point discrimination test: touch finger with two pins participant says if they feel pin 1 or 2, test to see the smallest distance where participant is reliably correct. much better sensitivity in trained hand.
you can meausre the specific neuron by single cell recording
Ex: Showed neuron fired in animal when a tone went off between 0.7 and 3 kHz. it was tuned to 0.9 because that is where they had the most firing.
has place cells
contains a particular receptive field for a place that is familiar