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Learning : the acquisition of an altered behavioral response due to an environmental stimulus. Memory : the processes through which learned information is stored. Recall : the conscious or unconscious retrieval process through which this altered behavior is manifest. Suggested Reading.
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Learning: the acquisition of an altered behavioral response due to an environmental stimulus Memory: the processes through which learned information is stored Recall: the conscious or unconscious retrieval process through which this altered behavior is manifest
Suggested Reading • The Seven Sins of Memory by Daniel Schacter • Mechanisms of Memory by David Sweatt • Grain Brain by David Perlmutter • Memory From Mind to Molecules by Squire and Kandel
Neuron Neurons shapes and sizes from Univ. of Washington Marina Chicurel and Christopher DeFranceo, The Inner Life of Neurons: An empire of semi-independent domains, The Harvard Mahoney Neuroscience Institute Letter: On The Brain, Vol. 4 (Spring, 1995), http://www.med.harvard.edu/publications/On_The_Brain/Volume4/Number2/SP95In.html
Ion Channels John Travis, Channel Surfing: Atomic-resolution snapshots illuminate cellular pores that control ion flow, Science News Online, Vol. 161 (March 9, 2002), http://www.sciencenews.org/articles/20020309/bob8.asp Christof Koch, Biophysics of Computation: Information Processing in Single Neurons Oxford Univ. Press, Oxford, 1999, p. 7
Action Potential http://www.blackwellpublishing.com/matthews/channel.html adapted from J. Timothy Cannon, http://academic.uofs.edu/faculty/cannon/sp/02/ActionPotential.html, retrieved 3/30/04
Synapse Dale Purves, George Augustine, David Fitzpatrick, Lawrence Katz, Anthony-Samuel LaMantia, James McNamara, and Mark Williams, Neuroscience, Sinauer Associates, Sunderland, Massachusetts, 2001, p. 142. Cartoon
Expression of LTP • possible presynaptic mechanisms • increased probability of transmitter release in response to a presynaptic action potential • more transmitter released due to more sites of release • more transmitter released due to increased size of vesicles containing neurotransmitter • a presynaptic mechanism requires a retrograde messenger (e.g. nitrous oxide) to signal postsynaptic activity to the presynaptic terminal • possible postsynaptic mechanisms • increased sensitivity to transmitter due to more postsynaptic receptors for the neurotransmitter • increased sensitivity to transmitter due to increased conductance of individual receptors • evidence points to a combination of both possibilities
Potential Sites of Synaptic Modification in LTP Retrograde Signal Release Membrane Properties Glu Binding Reuptake • Postsynaptic= Altered • Number of AMPA receptors • Insertion of AMPA receptors • Ion flow through AMPA channels • Membrane electrical properties • Presynaptic= Altered • Neurotransmitter amount in vesicles • Number of vesicles released • Kinetics of release • Glutamate reuptake • Probability of vesicle fusion Additional possibilities include changes in number of total synaptic connections between two cells
Mechanisms for E-LTP Cytoskeleton Changes 2 K+ Channels Phosphorylation & Insertion 2 ? AMPAR 1 3 *CaMKII ? Synaptic Tag 2 ? *PKC Release Process 3 1 Protein Synthesis ? Ca++ *PKC NMDAR *PKMzeta 1 1 Retrograde Messenger? *= Persistently Activated
How to reduce chances of Dementia and Alzheimer’s • Diet – low calorie, high fat, high protein, low carb, high Omega-3 low Omega-6, blueberries, anti-oxidants • Physical activity • Mental activity • Cholesterol levels – high cholesterol good? • Hormone levels
Need volunteers • 2-3 actors • 1 still photographer • 1 video photographer • Need to be here 30 minutes early next week
Sins of Memory (Omission) • Transience – weakening or loss of a memory over time • Absent-mindedness – info not registered due to distraction • Blocking – search for info we know, but can’t retrieve
Sins of Memory - Commission • Misattribution – assigning a memory to the wrong source • Suggestibility – memory implanted as a result of suggestions • Bias – influence of current knowledge and beliefs on memory • Persistence – repeated recall of disturbing memory that we would rather forget