Learning and Memory

1. Learning and Memory The story of HM Types of memories How memories are stored

2. Do Now • Where is long term memory created in the brain? • It is stored in the hippocampus. • And where is this part of the brain located?(What lobe?) • In the Temporal Lobe

3. Hippocampus • The hippocampus belongs to the limbic system and plays important roles in the consolidation of information from short-term memory to long-term memory and spatial navigation. • Humans and other mammals have two hippocampi, one in each side of the brain.

4. The story of H.M. • H.M. had epilepsy • So he had parts of his medial temporal lobe removed • He could then no longer form long-term memories of his experiences • http://www.youtube.com/watch?v=LBsW5qz5sDU • http://www.youtube.com/watch?v=hqi1xo658NE

5. Review • H.M. had parts of what lobe removed? medial temporal lobe • What structures that are in this lobe were removed? Hippocampus & parahippocampal region • What happened because these structures were removed? Unable to convert short term to long term memory

6. TYPES OF MEMORY

7. Types of Memories • Declarative – conscious memory of facts/events • First enters as working memory (WM) (transient) • The prefrontal cortex can combine info in WM with other relevant info • Executive functions – selection, rehearsal, etc. • Can help put info from WM into long-term storage

8. Prefrontal Cortex • The prefrontal cortex is responsible for workingmemory. • Combines sensory information into memories. • Prefrontal cortex is activated in humans when memories are manipulated.

9. Delayed Non-Match to Sample

10. Striatum & Procedural Memory;Prefrontal Cortex & Working Memory

11. Types of Declarative Memories • Semantic – data and facts • There are different zones for different types of data • Episodic – experiences and events • Parts of the parahippocampal region help process the “what/when/where” of events

12. What is the capital of Washington • Olympia: • This was an example of__________ memory. semantic

13. Where did you learn the capitals of the states? Who taught them to you? • This was an example of__________ memory. episodic

14. Types of Memories • Nondeclarative memories – remembering howto do something, or memories you have no conscious recollection of • Requires processing by basal ganglia and cerebellum. Why? The Basal Ganglia play an important role in planning and coordinating motor movements and posture.

15. Types of Memories • EXAMPLE OF Nondeclarative memories – • For example, when an amnesic patient was stuck by a pin when she tried to shake hands with a physician, she later refused to shake hands although she had no memory of ever having met the doctor before. When asked why she refused to shake, she answered that she didn't really know, but that sometimes people hid pins in their hands. • http://brainmind.com/Amnesia.html

16. Emotion in Memory • The amygdala plays an important role in the emotional aspects of memory. • The hypothalamus and the sympathetic nervous system support emotional reactions and feelings • For example, the movie Titanic.

17. Review • What is the knowledge of how to do a skill? • Nondeclarative knowledge • What is another word for nondeclarative knowledge? • Procedural memory • What parts of the brain play an important role in emotional memory? • Amygdala, hypothalamus, and the sympathetic nervous system.

18. More Review • What is declarative memory? Conscious memory of facts and events • What is semantic memory? Type of declarative memory for facts and data • What is episodic memory? Type of declarative memory of events • What is working memory? Working with information. Reason, comprehend and manipulate transient information. • What is nondeclarative memory? Remembering how to do something

19. How are memories stored? • Involves changes in synapses between two neurons • LTP (long-term potentiation) – long-lasting increase in the strength of a synapse

20. Long-term potentiation (LTP) • As a long-lasting enhancement in signaltransmission between two neurons that results from stimulating them synchronously. • It is one of several phenomena underlying synaptic plasticity, the ability of synapses to change their strength.

21. LTP (more than you need to know for your quiz) • What do you remember about glutamate and the 2 different glutamate receptors? • NMDA receptor (cation channel) is blocked by Mg2+ at resting membrane potential. • To unblock the channel, the postsynaptic cell must be depolarized. Glutamate is an Excitatory NT, and has NMDA and AMPA receptors

22. LTP • Involves NMDA receptors, which allow calcium ions to enter. • Once calcium enters…

25. LTP (more than you need to know for your quiz) • SO, NMDA cannot be utilized unless the cell has already received a signal to cause depolarization. • Therefore, the NMDA receptor functions as a "molecular coincidence detector".

26. LTP (more than you need to know for your quiz) • Its ion channel opens only when the following two conditions are met simultaneously: • Glutamate is bound to the receptor, and the postsynaptic cell is depolarized (which removes the Mg2+ blocking the channel). • This property of the NMDAreceptor explains many aspects of long-term potentiation (LTP) and synaptic plasticity

27. LTP • Glutamate binds to postsynaptic AMPARs and another glutamate receptor, the NMDAR. • Ligand binding causes the AMPARs to open, and Na+ flows into the postsynaptic cell, resulting in a depolarization. • NMDARs, on the other hand, do not open directly at resting membrane potential they are blocked Mg2+ ions.

28. LTP • NMDARs can open only when a depolarization from the AMPAR activation leads to repulsion of the Mg2+ cation out into the extracellular space, allowing the pore to pass current. • Unlike AMPARs, however, NMDARs are permeable to both Na+ and Ca2+. • The Ca2+ that enters the cell triggers the upregulation of AMPARs to the membrane, which results in a long-lasting increase in EPSP size underlying LTP.

30. Model for LTP Induction

31. Question Time! • Describe LTP This causes long-lasting increase in the strength of a synapse

32. Videos to watch • http://www.youtube.com/watch?v=euINCrDbbD4

33. Language & the Brain

34. Neural Basis for Language is Complex • What is language? • spoken, written, nonverbal communication • What senses do you need? • vision, hearing • proprioception • What processes occur? • Motor processes • Memory processes (long-term, short-term / working memory) • Higher order / abstract reasoning (symbolism)

35. Aphasia= Impaired Language Ability Understanding speech (Wernicke’s area) Speech production (Broca’s area) ***In some people, the right hemisphere is the dominant hemisphere for language. For this group of people, Broca’s area and Wernicke’s area will be located in the right hemisphere. http://commons.wikimedia.org/wiki/File:Brain_Surface_Gyri.SVG

36. Guess the type of aphasia!

37. Guess the type of aphasia!

38. Answers • First clip = Wernicke’s Aphasia • Nonsense speech, but is spoken at a normal speed and some complex words are used • Second clip = Broca’s Aphasia • Meaning of words used correctly, but it’s hard to get the words out

39. Word deafness • Cause by damage to the superior temporal lobes in both hemispheres • Inability to comprehend any auditory speech

40. Language throughout the brain Frontal lobe and posterior temporal lobe (left): Speech production Anterior temporal lobe: Sentence-level comprehension Middle and Inferior Temporal Lobe: Accessing the meaning of words Left Posterior Temporal Lobe: Sensory-motor circuit; supports verbal short-term memory http://en.wikipedia.org/wiki/File:BrainLobesLabelled.jpg

41. Genetics • Inherited disorders can impede the development of fluent speech and language. • For example, rare mutations of a gene called FOXP2 • impede learning to make sequences of mouth and jaw movements that are involved in speech, accompanied by difficulties that affect both spoken and written language.

42. Genetics • The FOXP2 gene codes for a special type of protein that switches other genes on and off in particular parts of the brain. • Changes in the sequence of this gene may have been important in human evolution.