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Memory

Memory. Cellular and Molecular Basis of Memory Engram Temporal Types of Memory. Memory. ability to accept information (encoding) to store (storage) to retrieve (retrieval) information from NS. Memor y involves at least four distinct processes:.

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Memory

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  1. Memory Cellular and Molecular Basis of Memory Engram Temporal Types of Memory

  2. Memory ability to accept information (encoding) to store (storage) to retrieve (retrieval) information from NS

  3. Memory involves at least four distinct processes: Encoding - incoming information must be perceived Consolidation – newly stored information is labile, to make it more stable (expression of genes, structural changes Storage- to retain over time, almost unlimited capacity Retrieval – to bring different kinds of information together, it is constructive process, subject to distortion

  4. ConsolidationRetrograde amnesia A person who has been knocked unconscious selectively loses memory for events that occured before the blow

  5. Retrieval recall (reproduction) - serial - free recall - cued record (with help, hint) (reproduction of paired associations) Recognition (to recognize again)

  6. Memory vs learning • Engram (print, foot-mark) • Memory is not homogeneous • Duration, persistence • Brain structures • Molecular mechanisms

  7. Donald Olding Hebb *1904 †1985 Canadian psychologist Hebb's Law. "Neurons that fire together wire together." • Hebbian theory: • When an axon of cell A is near enough to excite cell B and repeatedly or persistently takes part in firing it, some growth process or metabolic change takes place in one or both cells such that A's efficiency, as one of the cells firing B, is increased

  8. Eric Richard Kandel • 1929 Vienna • 2000 Nobel Prize in Physiology or Medicine Experimental support for Hebbian learning The California sea slug (Aplysia californica) is also commonly called the California sea hare, and this is because the shape of all Aplysia species is reminiscent of the shape of a rabbit or hare. Sea hares are a kind of shell-less sea snail, a marine mollusk

  9. Molecular mechanisms • Posttetanic potentiation (short term potentiation) Long term potentiation LTP

  10. Posttetanic potentiation

  11. Posttetanic potentiation Large Ca2+ influx. Saturation of the various Ca2+ buffering systems (ER, mitochondia) Temporary excess of Ca2+ is called residual Ca2+. Concentration of free Ca2+ increases the amount of transmitter released

  12. Posttetanic potentiation A hight rate of stimulation of the presynaptic neuron A gradual increase in the amplitude of the postsynaptic potential Postsynaptic potential increases in size = potentiation

  13. Posttetanic potentiation The enhancement in the strength of the synapse represents storage of information about previous activity It can lasts minutes but can persist for an hour. An elementary form of memory

  14. Long term potentiation LTP

  15. NMDA – glutamate receptor

  16. Glutamate receptors

  17. Long term potentiation LTP Glutamate synapse Both NMDA and AMPA receptors

  18. Long term potentiation LTP Increase the sensitivity Increase the number of postsynaptic AMPA receptors retrograde messenger (NO)

  19. Long term potentiation LTP Postsynaptic part NMDA redeptor retrograde messenger (nitric oxide) Presynaptic part NO initiate an enhancement of transmitter release that contributes to LTP

  20. Long term potentiation LTP New synapses Ca2+ + calmodulin Transcription - mRNA Translation - proteins

  21. Long term potentiation LTP Increase in the sensitivity and number of postsynaptic AMPA receptors retrograde messenger NO (enhancement of transmitter release ) New synapses

  22. Temporal phases of memory(based on different biological mechanisms)

  23. Iconic (visual) – reflect the activity of sensory buffers, continuation of sensory neural activity Short-term memories – last for seconds up to a minutes Long-term memory – weeks, months, years, for the rest of the life of an organism (permanent memory) Working memory (short-term plus activated long term memory)

  24. A scheme of memory processes that includes encoding, consolidation and retrieval

  25. Iconic (visual) echoic (auditory) – reflects the activity of sensory buffers, continuation of sensory neural activity Iconic memory (visual persistence, example burning ring) George Sperling 1960 Experiment: whole-report procedure Presentation 50 ms Recall of 3-5 symbols In Sternberg R.J.: Kognitivní psychologie, Portál, Praha 2002: s. 187.

  26. Iconic (visual) George Sperling 1960 Experiment: partial-report procedure Presentation 50 ms Cued recall – The frequency of the tone (high, medium, or low) indicated which set of characters within the display were to be reported Recall of 9 symbols Sperling's original partial report paradigm Iconic memory is described as a very brief (<1000 ms), pre-categorical, high capacity memory store

  27. Short-term memories last for seconds up to a minutes capacity 7 ± 2 items

  28. Verbal memory AVLT Auditory Verbal Learning Test Remember folowing words

  29. Verbal memory 1. table 2. cloud 3. bookcase 4. tree 5. shirt 6. cat 7. light 8. dick 9. bench 10. chalk 11. flower 12. bat 13. blanket 14. soap 15. pillow AVLT Who recall word table light bench pillow Dick

  30. Verbal memory Ebinghaus curve order in series What is first What is fresh (last word)

  31. Verbal memory Better memory for What concern you personally Personally interesting Unusual Connected with emotions erotic subtext

  32. Comparison of verbal and visual memory

  33. Explore each picture

  34. Write down names of things

  35. Envelope Music Bird Brush Palette Tin Screwdriver Telephone Fireman Stairs Dustbin Bike Money Hen Lettuce Interactive image

  36. Long term memory Pacient H.M.

  37. H.M. was taught to trace between two outlines of a star while viewing his hand in a mirror

  38. Regions of the human brain that have been implicated in the formulation of long-term declarative memories. A lateral view of the brain shows the levels of the transverse sections Cross sections in two levels

  39. Declarative Explicit Nondeclarative Implicit Episodic Store events autobiographical Semantic Non associative Associative learning Long term memory classification

  40. Declarative Explicit Nondeclarative Implicit Episodic Store events autobiographical Semantic Non associative Associative learning Long term memory classification

  41. Epizodic-like memory test

  42. Declarative Explicit Nondeclarative Implicit Epizodic Store events autobiografic Semantic Store facts Non associative Associative learning Long term memory classification

  43. Morris water maze

  44. Temporal lobe lesion

  45. Blue velvet arena

  46. Test: Hidden goal in Blue velvet arena Alzheimer disease Vascular dementia Control group Mild cognitive impairment

  47. Epizodic-like memory test

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