Presentation is loading. Please wait.

Presentation is loading. Please wait.

CART Celebration May 2010 How Learning Changes the Physiology and Structure of the Brain Ahmed M. Abdelal, Ph.D., CCC-SLP Assistant Professor of Communication.

Similar presentations


Presentation on theme: "CART Celebration May 2010 How Learning Changes the Physiology and Structure of the Brain Ahmed M. Abdelal, Ph.D., CCC-SLP Assistant Professor of Communication."— Presentation transcript:

1

2 CART Celebration May 2010 How Learning Changes the Physiology and Structure of the Brain Ahmed M. Abdelal, Ph.D., CCC-SLP Assistant Professor of Communication Sciences & Disorders Department of Special Education & Communication Disorders

3 Brain Function and Neuroal Transmission Basic Brain Landmarks Basic Brain Landmarks Presynaptic neurons Presynaptic neurons Postsynaptic neurons Postsynaptic neurons Synaptic cleft Synaptic cleft Neural transmission Neural transmission

4

5

6

7

8

9

10 DISTINCTION BETWEEN MEMORY & LEARNING

11 Memory Memory refers to “A number of different brain functions. The common feature of these functions is the re-creation of past experiences by the synchronous firing of neurons that were involved in the original experience.” (Carter, et al 2009, 154)

12 Our Memories Are Always Subjective “Our memories are personal and evocative, intertwined with emotion, and they provide us with a sense of who we are.” (Squire & Kandel 2010, 75)

13 Learning “Learning is the process in which neurons that fire together to produce a particular experience are altered so that they have a tendency to fire together again. The subsequent combined firing of the neurons reconstructs the original experience, producing a ‘recollection’ of it. The act of recollecting makes the neurons involved even more likely to fire again in the future.” (Carter, et al 2009, 154)

14 Relationship Between Learning & Memory Leaning is “the process by which we acquire knowledge about the world, while memory is the process by which that knowledge is encoded, stored, and later retrieved” (Kandel, Schwartz, & Jessell, 2000, p. 1227) (Kandel, Schwartz, & Jessell, 2000, p. 1227)

15 Types of Memory: Type of Experience Procedural/implicit Procedural/implicit Learned actions (routines & procedures) Learned actions (routines & procedures) Declarative/explicit Declarative/explicit Episodic Episodic Sensations & emotions (personal) Sensations & emotions (personal) Semantic Semantic Factual, non-personal information Factual, non-personal information

16 Types of Memory Based on Duration Immediate memory Immediate memory Capacity of 7 items Capacity of 7 items Only 30 seconds, if info not rehearsed Only 30 seconds, if info not rehearsed Working Memory (WM) Working Memory (WM) Phonological loop (verbal info) Phonological loop (verbal info) Visuospatial sketch pad (faces, images, spatial layouts) Visuospatial sketch pad (faces, images, spatial layouts) WM sustains info for 0.5 sec. to 10 min. WM sustains info for 0.5 sec. to 10 min. Long-term memory Long-term memory

17 Neural Plasticity “The ability of the nervous system to form new synaptic connections and reconfigure old connections in response to experience or injury” (Byrnes 2001, p. 192)

18 Neural Plasticity … Means that brain wiring is not constant Means that brain wiring is not constant Includes any type of brain changes Includes any type of brain changes Occurs throughout the lifespan Occurs throughout the lifespan Makes new learning possible Makes new learning possible Makes it possible to eliminate undesired behavior Makes it possible to eliminate undesired behavior Makes it possible to unlearn and forget Makes it possible to unlearn and forget

19 How Learning Changes Brain Structure Any type of learning must result in physical changes in brain structure: Any type of learning must result in physical changes in brain structure: Cellular changes Cellular changes Birth of new neurons (Neurogenesis) Birth of new neurons (Neurogenesis) Expansion of existing networks Expansion of existing networks Creation of new circuits Creation of new circuits

20 How Learning Changes Brain Structure Cellular changes in the existing neurons: Cellular changes in the existing neurons: Strengthening existing synaptic connections Strengthening existing synaptic connections Growth of new synaptic branches and production of neurotransmitter components in presynaptic neurons Growth of new synaptic branches and production of neurotransmitter components in presynaptic neurons Translation and transcription of specific genes Translation and transcription of specific genes Production of new receptor proteins and inserting them along the membrane of the postsynaptic neuron Production of new receptor proteins and inserting them along the membrane of the postsynaptic neuron

21

22 Primary Centers of Learning Hippocampus Hippocampus Amygdala Amygdala Medial temporal lobe Medial temporal lobe PF cortex PF cortex Association cortices Association cortices

23 © A. Abdelal, Ph.D., CCC-SLP

24 Hippocampus & Amygdala

25 Phases of Learning For information to be retained in LT memory, it has to be processed in phases For information to be retained in LT memory, it has to be processed in phases Each phase involves specific neural pathways, and structural modifications Each phase involves specific neural pathways, and structural modifications Perception Perception Pre-encoding Pre-encoding Encoding Encoding Transfer Transfer Imprinting Imprinting Storage Storage Retrieval Retrieval Consolidation Consolidation

26 Setting the Stage for Learning Motivation and emotional response direct our attention Motivation and emotional response direct our attention Information cannot enter into the memory system unless it is attended to Information cannot enter into the memory system unless it is attended to Attend to a piece of info for about 0.2 sec. Attend to a piece of info for about 0.2 sec. Attention intensifies the experience by triggering neurons to fire more frequently Attention intensifies the experience by triggering neurons to fire more frequently The more a neuron fires the stronger its connections are with other neurons The more a neuron fires the stronger its connections are with other neurons

27 Preparatory Phase: Pre-encoding Mechanism There are specific areas “pre-prepared to store new information, even before the stimuli are collected and coded” There are specific areas “pre-prepared to store new information, even before the stimuli are collected and coded” If these areas are activated in time for encoding, encoding & recall will efficient If these areas are activated in time for encoding, encoding & recall will efficient This pre-encoding circuit is activated by: This pre-encoding circuit is activated by: Good self-esteem Good self-esteem Strong motivation Strong motivation Positive attitude (Atlas of Human Physiology, 2009, ) Positive attitude (Atlas of Human Physiology, 2009, )

28 Working Memory & Executive Functions Executive functions: location? Executive functions: location? Develop, pursue & focus on goals; sustain attention, allocate attentional resources, monitor our own work toward the goal; regulate our behavior, etc. Develop, pursue & focus on goals; sustain attention, allocate attentional resources, monitor our own work toward the goal; regulate our behavior, etc. Behavioral inhibition suppresses distractions Behavioral inhibition suppresses distractions Working Memory: PFC  Sensory center Working Memory: PFC  Sensory center Holds material to guide on-going behavior and cognition Holds material to guide on-going behavior and cognition Info gets shuttled back and forth from frontal cortex to the sensory cortex that initially registered it. Info gets shuttled back and forth from frontal cortex to the sensory cortex that initially registered it.

29 Encoding The process by which new information is attended to and processed when it is first encountered (Kandel et al., 2000) The process by which new information is attended to and processed when it is first encountered (Kandel et al., 2000) Mediated by the hippocampus & PFC Mediated by the hippocampus & PFC New info reaching the hippocampus induces activation of pathways to previous info New info reaching the hippocampus induces activation of pathways to previous info

30 What Happens During Encoding Activation of previous information Activation of previous information Evaluation of the new information Evaluation of the new information Analysis Analysis Organization Organization Integration Integration Reassembling and synthesis Reassembling and synthesis

31 Encoding Mechanisms Neurotransmitters Neurotransmitters Noreadrenaline/Norepinephrine Noreadrenaline/Norepinephrine Acetylcholine Acetylcholine Serotonin Serotonin Dopamine Dopamine Proteins Proteins C-Kinase C-Kinase Synapsin 1 Synapsin 1

32

33 Role of Hippocampus in Encoding LT Potentiation LT Potentiation Site for incoming information Site for incoming information Directly connected with emotional processing & long-term storage sites Directly connected with emotional processing & long-term storage sites Determines what info to be selected for LT storage Determines what info to be selected for LT storage Assembly site for info being retrieved Assembly site for info being retrieved

34 Neurogenesis During Encoding Occupies the first 20 minutes of learning Occupies the first 20 minutes of learning Newly born neurons immediately enter the memory pathways individually Newly born neurons immediately enter the memory pathways individually Enter Enter Exit Exit Re-enter and stay Re-enter and stay They appear to imprint the new information and integrate it with previous information They appear to imprint the new information and integrate it with previous information They mediate forgetfulness of irrelevant information They mediate forgetfulness of irrelevant information

35 Efficiency of Encoding Encoding determines the efficiency of retrieval. Encoding determines the efficiency of retrieval. Efficiency of retrieval depends on the cues & strategies used while the info is being encoded, rather than the strategies used during the retrieval process. Efficiency of retrieval depends on the cues & strategies used while the info is being encoded, rather than the strategies used during the retrieval process.

36 What Determines Efficiency of Encoding Emotional content of the info: happy vs sad Emotional content of the info: happy vs sad Motivation & level of interest cause deep encoding and subconscious rehearsal Motivation & level of interest cause deep encoding and subconscious rehearsal Effort learner puts into practicing recall of info Effort learner puts into practicing recall of info Novelty (Carter et al, 2009, 154) Novelty (Carter et al, 2009, 154) Extent to which the info is: Extent to which the info is: Organized Organized Related to previous knowledge Related to previous knowledge Rehearsed after it has been presented Rehearsed after it has been presented (Squire & Kandel 2009, 74)

37 Efficiency of Encoding: Elaborative Encoding Elaborative/deep encoding is better than shallow/superficial encoding Elaborative/deep encoding is better than shallow/superficial encoding Breaking down info Breaking down info Discussing the meaning of each part Discussing the meaning of each part Relating the info to previous knowledge Relating the info to previous knowledge Asking questions in the process Asking questions in the process Example Example

38

39 Implications for Teaching Testing promotes “better long-term retention than restudying” (Squire & Kandel 2009, 77). Testing promotes “better long-term retention than restudying” (Squire & Kandel 2009, 77). Students perform better when they know test format ahead of time. Students perform better when they know test format ahead of time. Focusing on concepts is best for essay tests Focusing on concepts is best for essay tests Focusing on details is best study for multiple- choice tests Focusing on details is best study for multiple- choice tests Visual presentation is extremely powerful: “Nearly half of the cortex is dedicated to processing visual information” (Squire & Kandel 2009, 77) Visual presentation is extremely powerful: “Nearly half of the cortex is dedicated to processing visual information” (Squire & Kandel 2009, 77)

40 Transfer Starts within about 20 minutes Starts within about 20 minutes The medial prefrontal cortex directs the information through a monodirectional pathway: hippocampus  entorhinal cortex  perirhinal cortex The medial prefrontal cortex directs the information through a monodirectional pathway: hippocampus  entorhinal cortex  perirhinal cortex Neurotransmitters Neurotransmitters Serotonin, Norepinephrine, Acetylcholine, oxitocin Serotonin, Norepinephrine, Acetylcholine, oxitocin

41

42 Imprinting and Storage Storage: “The mechanisms and sites by which memory is retained over time” Storage: “The mechanisms and sites by which memory is retained over time” (Kandel et al., 2000) Initiated around one hour post learning Initiated around one hour post learning Imprinting is the initial step in the storage process Imprinting is the initial step in the storage process Imprinting starts one hour after learning, and lasts 25 hours Imprinting starts one hour after learning, and lasts 25 hours Mediated by special neurons called Imprinting Stimulus Neurons (IS neurons) Mediated by special neurons called Imprinting Stimulus Neurons (IS neurons)

43 Retrieval The process of recalling stored information through reactivating the pattern or pathways in which the information was originally stored. The process of recalling stored information through reactivating the pattern or pathways in which the information was originally stored. (Nelson, 2005) Retrieval is a reconstructive process that involves pulling pieces of info from various storage sites and integrating them into a coherent whole. Retrieval is a reconstructive process that involves pulling pieces of info from various storage sites and integrating them into a coherent whole.

44 Retrieval … Either involuntary or intentional Either involuntary or intentional Intentional retrieval is required for adequate academic performance and similar goal-directed behavior. Intentional retrieval is required for adequate academic performance and similar goal-directed behavior. Requires: Requires: Executive functioning & WM Executive functioning & WM Attentional resources Attentional resources Strategic memory searching Strategic memory searching

45 Retrieval … Involves gene expression and protein synthesis and insertion along pathways Involves gene expression and protein synthesis and insertion along pathways Any interruption of these cellular processes (e.g., stress, alcohol, etc.) prevents the formation of long-term memories Any interruption of these cellular processes (e.g., stress, alcohol, etc.) prevents the formation of long-term memories Info becomes temporarily unstable & vulnerable to distortion Info becomes temporarily unstable & vulnerable to distortion Followed by re-writing of the new info. Followed by re-writing of the new info.

46 Retrieval … Reactivation of a verbal pathway takes about one second Reactivation of a verbal pathway takes about one second Reactivation of a visual pathway takes 0.5 second Reactivation of a visual pathway takes 0.5 second Complex information may require several minutes Complex information may require several minutes

47 Retrieval … The more frequently the information is retrieved, the stronger the pathway, and the faster the activation The more frequently the information is retrieved, the stronger the pathway, and the faster the activation Information not retrieved for an extended period of time might take longer to reactivate or might be forgotten Information not retrieved for an extended period of time might take longer to reactivate or might be forgotten Context & Strength of cues are related to strength of retrieval Context & Strength of cues are related to strength of retrieval Retrieval is best when in same context and in presence of initial cues used during encoding Retrieval is best when in same context and in presence of initial cues used during encoding

48 Retrieval … Previous knowledge promotes efficient recall of new information Previous knowledge promotes efficient recall of new information Experts have superior abilities in remembering info related to there area of expertise, but “have no special gift for recalling details that are not meaningful to their area of expertise” Experts have superior abilities in remembering info related to there area of expertise, but “have no special gift for recalling details that are not meaningful to their area of expertise” Memory exercises do not improve retrieval Memory exercises do not improve retrieval (Squire & Kandel 2009, 77-78)

49 Consolidation The process by which information becomes stable and more resistant to interference, or the enhancement of the information through off-line processing between training sessions. (R obertson et al., 2004; Walker 2005)

50 Consolidation Long-lasting, dynamic process Long-lasting, dynamic process Involves integration of procedural and declarative knowledge Involves integration of procedural and declarative knowledge Requires gene expression and protein synthesis Requires gene expression and protein synthesis Involves interactions among numerous brain systems to organize, update, or strengthen existing memories. Involves interactions among numerous brain systems to organize, update, or strengthen existing memories.

51 Consolidation Mostly occurs during sleep Mostly occurs during sleep Facilitated by frequent retrieval/rehearsal Facilitated by frequent retrieval/rehearsal Starts one week after information is delivered Starts one week after information is delivered Lasts for up to 2 years Lasts for up to 2 years The long duration provides time for cerebral cortex to perform the required modifications The long duration provides time for cerebral cortex to perform the required modifications Newly consolidated information is flexible and modified frequently Newly consolidated information is flexible and modified frequently

52 Consolidation of Learning Mediated by pathways involving Medial temporal lobe Medial temporal lobe Hippocampus Hippocampus PFC PFC Sensory centers Sensory centers

53 Conclusion Learning is a life-long, dynamic process Learning is a life-long, dynamic process Any type of learning produces physical & structural changes in the brain Any type of learning produces physical & structural changes in the brain Learning is encoded and stored in stages and requires time Learning is encoded and stored in stages and requires time The lengthy consolidation allows the brain time to re- configure itself in response to the new information The lengthy consolidation allows the brain time to re- configure itself in response to the new information Mood & Motivational states play a major role in determining the efficiency of encoding and retrieval of new learning Mood & Motivational states play a major role in determining the efficiency of encoding and retrieval of new learning

54


Download ppt "CART Celebration May 2010 How Learning Changes the Physiology and Structure of the Brain Ahmed M. Abdelal, Ph.D., CCC-SLP Assistant Professor of Communication."

Similar presentations


Ads by Google