neuroscience of learning & memory
TRANSCRIPT
![Page 1: Neuroscience of Learning & memory](https://reader034.vdocuments.site/reader034/viewer/2022042619/58e58f0d1a28abdd148b50d1/html5/thumbnails/1.jpg)
Learning & Memory
![Page 2: Neuroscience of Learning & memory](https://reader034.vdocuments.site/reader034/viewer/2022042619/58e58f0d1a28abdd148b50d1/html5/thumbnails/2.jpg)
Learning
• According to Eric Kandel “Learning is a process by which we acquire knowledge about the world”
• Kimble “Learning refers to more or less permanent change in behaviour which occurs as a result of practice”
![Page 3: Neuroscience of Learning & memory](https://reader034.vdocuments.site/reader034/viewer/2022042619/58e58f0d1a28abdd148b50d1/html5/thumbnails/3.jpg)
• Further definition says, “Learning is either a case of differential strengthening of one from a number of responses evoked by a situation of need or formation of receptor evoked connections”
![Page 4: Neuroscience of Learning & memory](https://reader034.vdocuments.site/reader034/viewer/2022042619/58e58f0d1a28abdd148b50d1/html5/thumbnails/4.jpg)
What is Memory ?
• According to Kandel “Memory is a process by which that knowledge of the world is encoded, stored and later retrieved”
![Page 5: Neuroscience of Learning & memory](https://reader034.vdocuments.site/reader034/viewer/2022042619/58e58f0d1a28abdd148b50d1/html5/thumbnails/5.jpg)
Types of Memory
Explicit
Episodic Semantic
Implicit
Associative Classica
leg:
pavlov’s experiment
OperantEg:
Pigeon pecks a key
Non- associative Hab
ituationEg: Dog arouse
d by tone
played
Sensitizatio
nEg: dog reacts to
less tone
![Page 6: Neuroscience of Learning & memory](https://reader034.vdocuments.site/reader034/viewer/2022042619/58e58f0d1a28abdd148b50d1/html5/thumbnails/6.jpg)
NEUROSCIENCE OF LEARNING AND MEMORY
![Page 7: Neuroscience of Learning & memory](https://reader034.vdocuments.site/reader034/viewer/2022042619/58e58f0d1a28abdd148b50d1/html5/thumbnails/7.jpg)
Explicit Memory
![Page 8: Neuroscience of Learning & memory](https://reader034.vdocuments.site/reader034/viewer/2022042619/58e58f0d1a28abdd148b50d1/html5/thumbnails/8.jpg)
• Different forms of learning are affected differentially by lesions in different locations
Defects in memory storage for object recognition
![Page 9: Neuroscience of Learning & memory](https://reader034.vdocuments.site/reader034/viewer/2022042619/58e58f0d1a28abdd148b50d1/html5/thumbnails/9.jpg)
• Hippocampal system does initial steps in long term memory storage
• Memories of single event can be stored in multiple locations
• Each new explicit memory is formed by 4 sequential processes
a) Encoding b) Consolidation c) Storage d) Retrieval
![Page 10: Neuroscience of Learning & memory](https://reader034.vdocuments.site/reader034/viewer/2022042619/58e58f0d1a28abdd148b50d1/html5/thumbnails/10.jpg)
Implicit Memory
• They are stored differently on how they are acquired
• Operant conditioning involves the straitum and cerebellum
• Classical, sensitization and habituation involves sensory and motor systems
![Page 11: Neuroscience of Learning & memory](https://reader034.vdocuments.site/reader034/viewer/2022042619/58e58f0d1a28abdd148b50d1/html5/thumbnails/11.jpg)
Processes of Learning
• Donald Hebb stated, “when a axon of cell A excites cell B and repeatedly or persistently takes part in firing it, some growth process of metabolic changes take place in one or both cells so that A’s efficiency as one of the cells firing B is increased”
![Page 12: Neuroscience of Learning & memory](https://reader034.vdocuments.site/reader034/viewer/2022042619/58e58f0d1a28abdd148b50d1/html5/thumbnails/12.jpg)
Habituation
•What happens in nervous system to produce habituation? •Experiments performed in Aplysia californica, the sea slug, were designed to address this problem
![Page 13: Neuroscience of Learning & memory](https://reader034.vdocuments.site/reader034/viewer/2022042619/58e58f0d1a28abdd148b50d1/html5/thumbnails/13.jpg)
![Page 14: Neuroscience of Learning & memory](https://reader034.vdocuments.site/reader034/viewer/2022042619/58e58f0d1a28abdd148b50d1/html5/thumbnails/14.jpg)
Sensitization
![Page 15: Neuroscience of Learning & memory](https://reader034.vdocuments.site/reader034/viewer/2022042619/58e58f0d1a28abdd148b50d1/html5/thumbnails/15.jpg)
1 •Axonic syanpse occurs •Serotonin (5 hydroxytryptamine) is released by pre and post synaptic axon• Activates G protein •Adenyl cyclase
2 •cAMP Produced •Activates cAMP dependent kinase•Close k channels•Opens ca channels
3 •Activation of 5HT pathway by tail stimulation , therefore causes more substance to be released by siphon stimulation •Leads to response by gills
![Page 16: Neuroscience of Learning & memory](https://reader034.vdocuments.site/reader034/viewer/2022042619/58e58f0d1a28abdd148b50d1/html5/thumbnails/16.jpg)
![Page 17: Neuroscience of Learning & memory](https://reader034.vdocuments.site/reader034/viewer/2022042619/58e58f0d1a28abdd148b50d1/html5/thumbnails/17.jpg)
• Short term tail stimulation • Long term tail stimulation • Structural changes occur in pre synaptic
terminals
![Page 18: Neuroscience of Learning & memory](https://reader034.vdocuments.site/reader034/viewer/2022042619/58e58f0d1a28abdd148b50d1/html5/thumbnails/18.jpg)
Long term potentiation
• Hippocampus is important storage for declarative memory
• High frequency train of stimuli applied to fibers afferent to hippocampus increase amplitude of EPSPs in target neuron
• Pre and post synaptic cells both be active at same time
![Page 19: Neuroscience of Learning & memory](https://reader034.vdocuments.site/reader034/viewer/2022042619/58e58f0d1a28abdd148b50d1/html5/thumbnails/19.jpg)
Experimental set up for demonstrating LTP
Made
Stimuli applied
Amplitudes Of post synaptic Potentials
For single stimulus
Hebbs rule at work
![Page 20: Neuroscience of Learning & memory](https://reader034.vdocuments.site/reader034/viewer/2022042619/58e58f0d1a28abdd148b50d1/html5/thumbnails/20.jpg)
Glutamate binds to metabotropic receptor, activating PLC and to NMDA receptors NMDA can bind glutamate but no current will flow through the channels unless Mg++ Is displaced
![Page 21: Neuroscience of Learning & memory](https://reader034.vdocuments.site/reader034/viewer/2022042619/58e58f0d1a28abdd148b50d1/html5/thumbnails/21.jpg)
High frequency stimulation opens glutamate Non NMDA channels leading to hypopolarization.This dislodges Mg++ , Ca++ enters the cell. Calcium triggers activity of Ca dependent kinases.Calcium calmodulin kinase phosphorylates non NMDA channels increasing their sensitivityTo glutamate and a messenger is sent to presyanptic terminal to increase the release of transmitter substance
![Page 22: Neuroscience of Learning & memory](https://reader034.vdocuments.site/reader034/viewer/2022042619/58e58f0d1a28abdd148b50d1/html5/thumbnails/22.jpg)
References • Learning and Memory http://michaeldmann.net/mann18.html• Neurobiology linster http://www.nbb.cornell.edu/• Learning and Memory by John H. Byrne, Ph.D.,
Department of Neurobiology and Anatomy, The UT Medical School at Houston http://neuroscience.uth.tmc.edu/s4/chapter07.html
![Page 23: Neuroscience of Learning & memory](https://reader034.vdocuments.site/reader034/viewer/2022042619/58e58f0d1a28abdd148b50d1/html5/thumbnails/23.jpg)
THANK YOU