Brain Development and Learning: Understanding the Genesis and Elimination of Neurons and Synapses
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先導型通識「生活中的生命科學」 第 8 單元 大腦心智的發展學習與記憶Learning and Memory 政治大學神經科學研究所 賴桂珍老師 本著作除另有註明外，採取創用CC「姓名標示－非商業性－相同方式分享」台灣2.5版授權釋出
Introduction • Operation of the brain • Precise interconnections among 100 billion neurons • Brain development • Connections formed and modified • Wiring in brain • Correct pathways and targets • Fine tuning
The Genesis of Neurons • Development of neuronal structure • Cell proliferation; Cell migration; Cell differentiation • Cell Proliferation
The Genesis Of Connections • Axon Guidance • Guidance Cues; Growth cones • Chemoattractant化學吸引物; Chemorepellent化學排斥物 Wiki Ashton W. Powell, Takayuki Sassa, Yongqin Wu, Marc Tessier-Lavigne Franck Polleux
The Genesis Of Connections Synaptic vesicle • Synapse突觸Formation Growing axon Presynaptic active zone Postsynaptic receptro cluster Filopodium Growing axon 必恩威亞太有限公司 張景婷
The Elimination Of Cells And Synapses • The mechanisms of pathway formation • Large-scale reduction in neurons and synapses • Development of brain function • Balance between genesis & elimination of cells and synapses • Cell Death 政治大學蘇品諺
The Elimination Of Cells And Synapses • Changes in Synaptic Capacity • Synapse elimination 政治大學蘇品諺
Synaptic Plasticity突觸可塑性 • Long-Term Synaptic Potentiation (LTP) • Role of the NMDAR • Unique properties • Voltage-gated ion channel • Calcium-permeable glutamate NMDAR AMPAR Mg2+ Ca2+ Ca2+ Ca2+ Ca2+ WikiRuth Drdla and Jürgen Sandkühler
Declarativememory (Medialtemporallobe;diencephalon) Nondeclarativememory Facts Events Proceduralmemory Skillsandhabits (Striatum) Skeletalmusculature (Cerebellum) Emotionalresponse (Amygdala) Classicalconditioning 政治大學趙知章
Types of Memory • Long-Term, Short-Term, and Working Memory • Working memory: Temporary information storage Short-term memory Consolidation Long-term memory Sensory information Consolidation Short-term memory Time 政治大學趙知章
學習（Learning） • 獲取（Acquisition） • 記憶（Memory） • 保留（Retention） • 陳述性記憶（Declarative memory） • 外顯性（explicit） • 面孔、事件 • 非陳述性記憶（Nondeclarative memory） • 內隱性（implicit） • 技能、習慣、行為
Types of Amnesia • Amnesia失憶症 • Memory loss related to time • Retrograde amnesia • Forget things you already knew • Anterograde amnesia • Inability to form new memories
The Search for the Engram • Hebb’s Cell Assembly and Memory Storage Wiki Barret Ruttan Wiki Barret Ruttan Wiki Nevit Dilmen
人的大腦 感覺,味覺,閱讀 視覺 運動 智能 頂葉 額葉 枕葉 顳葉 聽覺,嗅覺
The Temporal Lobes and DeclarativeMemory陳述性記憶 • The Medial Temporal Lobes and Memory Processing (Cont’d) • DNMS: Delayed non-match to sample • Medial temporal structures: Important for consolidation of memory
The Temporal Lobes and Declarative Memory • The Diencephalon and Memory Processing • Korsakoff’s Syndrome • Symptoms: Confusion, confabulations, severe memory impairment, and apathy • Alcoholics酗酒: Develop thiamin deficiency • Leads to symptoms: Abnormal eye movements, loss of coordination, tremors • Treatment: Supplemental thiamin • Thiamin deficiency: Structural brain damage
The Temporal Lobes and Declarative Memory • Memory Functions of the Hippocampus海馬迴 • Role of the medial temporal lobes • Declarative memory processing or consolidation WikiMcole13
The Temporal Lobes and Declarative Memory • Memory Functions of the Hippocampus • Spatial Memory and Place Cells • Morris water maze水迷宮 WikiSamueljohn.de
The Temporal Lobes and Declarative Memory • Memory Functions of the Hippocampus • Spatial Memory and Relational Memory 政治大學蘇品諺
Concluding Remarks • Learning and memory • Occur throughout the brain • Memories • Duration, kind of information stored, and brain structures involved • Distinct types of memory • Different types of amnesia • Multiple brain systems for memory storage
Procedural Learning • Associative Learning • Classical Conditioning Beforeconditioning Afterconditioning Conditioning WikiἘπαμεινώνδας 食物 (US) => 唾液分泌 (UR) 食物 (US) + 聲音 (NS) => 唾液分泌 (UR) 聲音 (CS) => 唾液分泌 (CR)
Vertebrate Models of Learning • Synaptic Plasticity in the Hippocampus • LTP and LTD • Key to forming declarative memories in the brain • Anatomy of Hippocampus • Brain slice preparation: Study of LTD and LTP
Vertebrate Models of Learning • LTP, LTD, and Glutamate Receptor Trafficking (Cont’d) Protein Phosphatase Presynaptic Postsynaptic [Ca2+]<1 µM LFS Calcium flux Unphosphorylated synaptic protein yields LTD Phosphorylated synaptic protein yields LTP 200 msec HFS Ca2+ influx Via NMDA receptors NMDA receptor [Ca2+]> 5 µM Protein kinase 必恩威亞太有限公司 張景婷
The Molecular Basis of Long-Term Memory • Phosphorylation磷酸化 as a long term mechanism: Problematic (transient and turnover rates) • Persistently Active Protein Kinases • Phosphorylation maintained: Kinases stay “on” • CaMKII and LTP • Molecular switch hypothesis 政治大學蘇品諺
The Molecular Basis of Long-Term Memory • Protein Synthesis • Requirement of long-term memory • Synthesis of new protein • Protein Synthesis and Memory Consolidation • Protein synthesis inhibitors • Deficits in learning and memory • CREB and Memory • CREB: Cyclic AMP response element binding protein
The Molecular Basis of Long-Term Memory • Protein Synthesis • Structural Plasticity and Memory • Long-term memory associated with formation of new synapses • Rat in complex environment: Shows increase in number of neuron synapses by about 25%