IB Psych II PowerPoint - Eric Kandel

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Johnia Murray
Imani Ross
IB Psychology II
1A
Background Info

 Kandel was a pioneer in moving the study of the
mind from an investigation of behavior to an
investigation of impulses
 Deals with learning and memory in the
hippocampus of the brain
 Memories don’t reside in a single, specific spot of the
brain
 Neural (neurons->synapses->impulses) change
occurs between the synapses
What is this?

Synapses

 Sites at the end of a neuron
 Place where nerve cells communicate with one
another
 Use neurotransmitters as messages to each other
Getting Down to
Specifics. . .

 1982 Experiment
 Eric Kandel and James Schwartz
 Observing changes in sending neurons
 Used a California sea snail, the Aplysia
Aplysia Study

 A California Sea Snail
 Observed changes in sending neurons
 Has 20,000+ unusually large nerve cells
 Classically conditioned (Ch. 8 from last year) the
snail to withdraw its gills when water is squirted at it
 Learning occurs
 Snail releases serotonin at certain synapses
 Becomes more efficient at transmitting signals
Aplysia Study cont’d

 NOVAscienceNOW – A Memorable Snail - PBS
 http://www.youtube.com/watch?v=yLa-cXg8BwM
Synapses and Memory

 Increased synaptic efficiency makes for a more
efficient neural circuit
 Sending neurons now need less imprinting to release
neurotransmitters
 The receiving neuron receptor cites may increase
 Long Term Potentiation
 a long-lasting strengthening of the response of a
postsynaptic nerve cell to stimulation across the
synapse that occurs with repeated stimulation and is
thought to be related to learning and long-term
memory
Synapses and Memory
cont’d

 LTP provides a neural basis for learning and
remembering associations (reference to Ch.8)
 Drugs that block LTP, interfere with learning
 At least 40 cognitive enhancers are currently in some
phase of development or clinical trial
 Target market: those with Alzheimer’s Disease, with
mild cognitive impairment
Hippocampus: Where is it
located?

Hippocampus

 Where initial events must come here in order to be
turned from short term to long term memory
 Short term memory is processed in the hippocampus
 Neurons have to cross over the synapses to leave a
mark or ‘tag’
 Declarative Memory
 A memory for fact and events
 People, places and objects
Hippocampus cont’d

 Contains a cognitive map of external environment
 Registers spatial information
 Space surrounding you (or animals)
 Registers single sensory modality
 Sight, sound, touch or pain
In short. . .

 Synaptic changes affect our learning ability and
memory
 Memories are stored in different places
 A lot of work is done in the hippocampus
 Don’t do drugs
 Snails are more than just slimy creatures that look
nasty
 There’s still a lot to be discovered about the brain
Reference List

 Myers, David G. (2006) Psychology (AP Edition).
:Macmillan – Worth Publishers.
 Mayford, Mark; Siegelbaum, Steven A; Kandel, Eric
R. (2012) Synapses and memory storage. CSH
Perspectives in Biology, 4(6). Retrieved from
http://cshperspectives.cshlp.org/content/4/6/a005
751.full
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