A Prototype of Brain Network Simulator for Spatiotemporal Dynamics of Alzheimer’s Disease一個模擬阿茲海默症之時空動態的腦網路模擬器原型<br />Spea...
Outline<br />Introduction<br />Motivation<br />Background and Related Work<br />The Brain Network Simulator<br />Design Co...
Introduction<br />It’s the Decade of Brain!<br />NIH Blueprint for Neuroscience Research<br />Grand Challenges<br />the co...
Motivation<br />Few studies by similar approach<br />Because the issue is extremely complex<br />But we’d loved to be the ...
Background and Related Work<br />2011/5/30<br />WECO Lab http://www.weco.net<br />5<br />
Background and Related Work<br />Brain informatics<br />An emerging interdisciplinary research field<br />Human Informatio...
Background and Related Work<br />The Human Connectome Project<br />Comprehensive map of neural connections in the human br...
by Connection Type
Anatomical connectivity
Functional connectivity
Effective connectivity
by Functionality
Thalamocortical Motifs
Polysynaptic Loop Structure
Diffuse Ascending Projections</li></li></ul><li>2011/5/30<br />WECO Lab http://www.weco.net<br />8<br />Basic Brain Networ...
Background and Related Work<br />Complex Network Analysis<br />Graph theory<br />targets: real life network<br />including...
Background and Related Work<br />Current Status of Brain Simulator<br />2011/5/30<br />WECO Lab http://www.weco.net<br />1...
The Brain Network Simulator<br />2011/5/30<br />WECO Lab http://www.weco.net<br />11<br />
The Brain Network Simulator<br />Design Concepts and Approaches<br />Architecture<br />Comparison between brain networks a...
The Brain Network Simulator<br />Design Concepts and Approaches<br />Architecture<br />Comparison between brain networks a...
The BrainNetwork Simulator<br />Internet vs. Brain Networks<br />2011/5/30<br />WECO Lab http://www.weco.net<br />14<br />
2011/5/30<br />WECO Lab http://www.weco.net<br />15<br />Layered Architecture of Brain Simulator<br />Short<br />Term<br /...
The Brain Network Simulator<br />Design Concepts and Approaches<br />Architecture<br />Comparison between brain networks a...
Connections are maintained by a sparse matrix to optimize memory usage<br />2011/5/30<br />WECO Lab http://www.weco.net<br...
2011/5/30<br />WECO Lab http://www.weco.net<br />18<br />
2011/5/30<br />WECO Lab http://www.weco.net<br />19<br />
2011/5/30<br />WECO Lab http://www.weco.net<br />20<br />
The Brain Network Simulator<br />Design Concepts and Approaches<br />Architecture<br />Comparison between brain networks a...
2011/5/30<br />WECO Lab http://www.weco.net<br />22<br />A Workflow Scenario of Brain Network Simulator<br />Signal Filter...
The Brain Network Simulator<br />Design Concepts and Approaches<br />Architecture<br />Comparison between brain networks a...
2011/5/30<br />WECO Lab http://www.weco.net<br />24<br />Case-based Incremental Delivery<br />Research or Experiment Resul...
Spatiotemporal dynamics of Alzheimer’s Disease<br />2011/5/30<br />WECO Lab http://www.weco.net<br />25<br />
Spatiotemporal dynamics of Alzheimer’s Disease<br />Three different models<br />Neuropathologicalstageing of Alzheimer-rel...
SIMULATE-ALZHEIMER’S-DISEASE(time t, network $s)<br />1  while time(t) < tend<br />2      affectedRegions[] ← GLOBAL-PATTE...
Spatiotemporal dynamics of Alzheimer’s Disease<br />Three different models<br />Neuropathologicalstageing of Alzheimer-rel...
Isocortical Areas<br />(including the belt fields and primary areas)<br />Stage III<br />Isocortex Association Area<br />S...
Isorcortex<br />Stage V & VI<br />Limbic Area<br />(involve the entorhinal and transentorhinal layer Pre-α)<br />Stage III...
Spatiotemporal dynamics of Alzheimer’s Disease<br />Three different models<br />Neuropathologicalstageing of Alzheimer-rel...
Remove Hubs<br />Hub<br />A Cluster<br />Three Cluster<br />Network Damage Model<br />2011/5/30<br />WECO Lab http://www.w...
2011/5/30<br />WECO Lab http://www.weco.net<br />34<br />Neurochemical Changes in Alzheimer’s Disease<br />Postsynaptic Ne...
2011/5/30<br />WECO Lab http://www.weco.net<br />35<br />Cholinergic Pathways<br />neocortex<br />cingulate<br />retrosple...
Spatiotemporal dynamics of Alzheimer’s Disease<br />Three different models<br />Neuropathologicalstageing of Alzheimer-rel...
Local View<br />Global View<br />5K<br />3.6<br />4K<br />2.0<br />1.2<br />1K<br />2011/5/30<br />WECO Lab http://www.wec...
2011/5/30<br />WECO Lab http://www.weco.net<br />38<br />∀ node 𝑖 in the network at time 𝑡,<br /> <br />𝜃𝑘𝑡𝑎𝑟𝑔𝑒𝑡−𝑘𝑖=1     ...
2011/5/30<br />WECO Lab http://www.weco.net<br />39<br />∀ target node in the network, the total decreased number of neuro...
2011/5/30<br />WECO Lab http://www.weco.net<br />40<br />∀ edge 𝒆in the network with source node 𝑺 and target node 𝑻, <br ...
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A Prototype of Brain Network Simulator for Spatiotemporal Dynamics of Alzheimer’s Disease

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Speaker: Jimmy Lu
Topics: A Prototype of Brain Network Simulator for Spatiotemporal Dynamics of Alzheimer’s Disease
Date: 2011.05.31

Defense of WECO Lab at CSIE, FJU

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A Prototype of Brain Network Simulator for Spatiotemporal Dynamics of Alzheimer’s Disease

  1. 1. A Prototype of Brain Network Simulator for Spatiotemporal Dynamics of Alzheimer’s Disease一個模擬阿茲海默症之時空動態的腦網路模擬器原型<br />Speaker : Jimmy Lu 盧松筠<br />Advisor : HsingMei 梅 興<br />Web Computing Laboratory (WECO Lab)<br />Computer Science and Information Engineering Department<br />Fu Jen Catholic University<br />
  2. 2. Outline<br />Introduction<br />Motivation<br />Background and Related Work<br />The Brain Network Simulator<br />Design Concepts and Development Approaches<br />Alzheimer’s Disease<br />Three Different Models<br />The Proposed Spatiotemporal Model of Alzheimer’s Disease<br />Implementation and Demo<br />Conclusion and Future Work<br />2011/5/30<br />WECO Lab http://www.weco.net<br />2<br />
  3. 3. Introduction<br />It’s the Decade of Brain!<br />NIH Blueprint for Neuroscience Research<br />Grand Challenges<br />the connectivity of the adult human brain<br />targeted therapy development for neurological diseases<br />Collaborative Works In the Multi-disciplinary Research Field<br />Computer Science plays a key role<br />Brain Network Simulator<br />Modeling structural and functional dynamics of the human brain<br />Apply to different cases (brain functions, diseases, cognition, behavior)<br />Keep evolving<br />education, research, diagnosis, personal health care, etc.<br />2011/5/30<br />WECO Lab http://www.weco.net<br />3<br />
  4. 4. Motivation<br />Few studies by similar approach<br />Because the issue is extremely complex<br />But we’d loved to be the pioneer<br />The start of the Human Connectome Project<br />Connection map will be the foundation of brain network simulator<br />The human brain is a large network<br />In IT research field, we have experience on real network analysis<br />The experiences can be inspirations for study brain networks<br />We believe simulation is the trend in the future of brain science studies<br />2011/5/30<br />WECO Lab http://www.weco.net<br />4<br />
  5. 5. Background and Related Work<br />2011/5/30<br />WECO Lab http://www.weco.net<br />5<br />
  6. 6. Background and Related Work<br />Brain informatics<br />An emerging interdisciplinary research field<br />Human Information Processing System (HIPS)<br />2011/5/30<br />WECO Lab http://www.weco.net<br />6<br />Web Intelligence<br />Deep Web Intelligence<br />Technology in web intelligence, especially in deep web intelligence, such as data mining, machine learning, and social network analysis, helps studies of brain science<br />Cognitive Science<br />Neuroscience<br />Brain Informatics<br />
  7. 7. Background and Related Work<br />The Human Connectome Project<br />Comprehensive map of neural connections in the human brain will be the foundation of studies of brain science<br />The-state-of-art neuroimaging technology<br />Macroscopic connectomes<br />2011/5/30<br />WECO Lab http://www.weco.net<br />7<br /><ul><li>Brain Networks
  8. 8. by Connection Type
  9. 9. Anatomical connectivity
  10. 10. Functional connectivity
  11. 11. Effective connectivity
  12. 12. by Functionality
  13. 13. Thalamocortical Motifs
  14. 14. Polysynaptic Loop Structure
  15. 15. Diffuse Ascending Projections</li></li></ul><li>2011/5/30<br />WECO Lab http://www.weco.net<br />8<br />Basic Brain Networks<br />(a) Thalamocortical Motif<br />GPe – External Global Pallidus<br />GPi – Internal Global Pallidus<br />STN – Subthalamic Nucleus<br />SNc – Substantia Nigra Compacta<br />SNr – Substantia Nigra Retuculata<br />DA – Dopamine<br />5-HT – Serotonin<br />Ach – Acetylcholine<br />(c) Diffuse Ascending Projections<br />(b) Polysynaptic Loop Structure<br />
  16. 16. Background and Related Work<br />Complex Network Analysis<br />Graph theory<br />targets: real life network<br />including brain networks<br />structure-function mapping<br />Alzheimer’s Disease<br />the most common dementia<br />unknown causes, incurable, degenerative, and terminal disease<br />four stages shows different patterns of impairments and symptoms on cognitive functions<br />lasts a long period of time<br />2011/5/30<br />WECO Lab http://www.weco.net<br />9<br />modules<br />shortest path<br />cluster<br />
  17. 17. Background and Related Work<br />Current Status of Brain Simulator<br />2011/5/30<br />WECO Lab http://www.weco.net<br />10<br />
  18. 18. The Brain Network Simulator<br />2011/5/30<br />WECO Lab http://www.weco.net<br />11<br />
  19. 19. The Brain Network Simulator<br />Design Concepts and Approaches<br />Architecture<br />Comparison between brain networks and the Internet<br />Layered architecture inspired by the Internet<br />Data Structure<br />Graph Structure: node and edge<br />Brain Components<br />thalamus<br />hippocampus<br />acetylcholine<br />Workflow<br />Development Approach<br />Case-based incremental delivery<br />2011/5/30<br />WECO Lab http://www.weco.net<br />12<br />
  20. 20. The Brain Network Simulator<br />Design Concepts and Approaches<br />Architecture<br />Comparison between brain networks and the Internet<br />Layered architecture inspired by the Internet<br />Data Structure<br />Graph Structure: node and edge<br />Brain Components<br />thalamus<br />hippocampus<br />acetylcholine<br />Workflow<br />Development Approach<br />Case-based incremental delivery<br />2011/5/30<br />WECO Lab http://www.weco.net<br />13<br />
  21. 21. The BrainNetwork Simulator<br />Internet vs. Brain Networks<br />2011/5/30<br />WECO Lab http://www.weco.net<br />14<br />
  22. 22. 2011/5/30<br />WECO Lab http://www.weco.net<br />15<br />Layered Architecture of Brain Simulator<br />Short<br />Term<br />Long<br />Term<br />Time Scale<br />Cognitive System<br />Aging<br />Brain Disease<br />Sleep<br />Decision Making<br />Neural Darwin Selection<br />Brain Disease Models<br />Resting State<br />Application Layer<br />(Behavior/Disease/Cognitive Functions)<br />……<br />Sleep Switch Model<br />Network Development Model<br />Network Damage Model<br />Reasoning<br />Causal Layer<br />(Overlays)<br />……<br />………<br />Processing Layer<br />Polysynaptic Loops<br />Diffuse Ascending Projection<br />Thalamocortical Motif<br />Brain Connectivity Layer<br />
  23. 23. The Brain Network Simulator<br />Design Concepts and Approaches<br />Architecture<br />Comparison between brain networks and the Internet<br />Layered architecture inspired by the Internet<br />Data Structure<br />Graph Structure: node and edge<br />Brain Components<br />thalamus<br />hippocampus<br />acetylcholine<br />Workflow<br />Development Approach<br />Case-based incremental delivery<br />2011/5/30<br />WECO Lab http://www.weco.net<br />16<br />
  24. 24. Connections are maintained by a sparse matrix to optimize memory usage<br />2011/5/30<br />WECO Lab http://www.weco.net<br />17<br />
  25. 25. 2011/5/30<br />WECO Lab http://www.weco.net<br />18<br />
  26. 26. 2011/5/30<br />WECO Lab http://www.weco.net<br />19<br />
  27. 27. 2011/5/30<br />WECO Lab http://www.weco.net<br />20<br />
  28. 28. The Brain Network Simulator<br />Design Concepts and Approaches<br />Architecture<br />Comparison between brain networks and the Internet<br />Layered architecture inspired by the Internet<br />Data Structure<br />Graph Structure: node and edge<br />Brain Components<br />thalamus<br />hippocampus<br />acetylcholine<br />Workflow<br />Development Approach<br />Case-based incremental delivery<br />2011/5/30<br />WECO Lab http://www.weco.net<br />21<br />
  29. 29. 2011/5/30<br />WECO Lab http://www.weco.net<br />22<br />A Workflow Scenario of Brain Network Simulator<br />Signal Filtering, Image Normalization, Transformation, etc.<br />Research or experiment results<br />Extract Required Information<br />Data Preprocessing<br />Instantiate Brain Components to Create Brain Anatomical Network<br />Input Data<br />time<br />Apply Theoretical Model for Simulation<br />Network Analysis<br />3D Brain Network Rendering<br />
  30. 30. The Brain Network Simulator<br />Design Concepts and Approaches<br />Architecture<br />Comparison between brain networks and the Internet<br />Layered architecture inspired by the Internet<br />Data Structure<br />Graph Structure: node and edge<br />Brain Components<br />thalamus<br />hippocampus<br />acetylcholine<br />Workflow<br />Development Approach<br />Case-based incremental delivery<br />2011/5/30<br />WECO Lab http://www.weco.net<br />23<br />
  31. 31. 2011/5/30<br />WECO Lab http://www.weco.net<br />24<br />Case-based Incremental Delivery<br />Research or Experiment Results<br />Personalized Medical data<br />New Cases<br />Case Study and Analysis<br />Existing Cases<br />Layered Architecture Extending and Refactoring<br />Cases Integration<br />Brain Components Extending and Refactoring<br />Feedback<br />Build Theoretical Models<br />Model Pool<br />Evaluate Theoretical Models<br />Evolved Brain Simulator<br />
  32. 32. Spatiotemporal dynamics of Alzheimer’s Disease<br />2011/5/30<br />WECO Lab http://www.weco.net<br />25<br />
  33. 33. Spatiotemporal dynamics of Alzheimer’s Disease<br />Three different models<br />Neuropathologicalstageing of Alzheimer-related changes<br />Describe global pattern of lesions caused by Alzheimer’s disease<br />Lesions: distribution of amyloid and neurofibrillary changes<br />Network Damage Model<br />Intentional attack on the node with highest degree<br />Observed in the brain affected by Alzheimer’s disease<br />Focus on fragments after attack<br />Treatment<br />Based on cholingeric hypothesis<br />Needs to find out the cholingeric pathways<br />A spatiotemporal model of Alzheimer’s Disease<br />A combination of three with temporal parameter added in<br />2011/5/30<br />WECO Lab http://www.weco.net<br />26<br />
  34. 34. SIMULATE-ALZHEIMER’S-DISEASE(time t, network $s)<br />1 while time(t) < tend<br />2 affectedRegions[] ← GLOBAL-PATTERN-OF-LESIONS(t)<br />4 for each region r∈affectedRegions[]<br />5 dotargetNodes[] ← CHOOSE-TARGET-NODES(t, r)<br />6 for each node n∈targetNodes[]<br />7 do compute the decreased number of neurons within n<br />8 do update s<br />9 for each edge e that connects to n<br />10 do compute the decreased number of connections<br />11 do re-compute the weight w of edge e<br />12 do update s<br /> <br />2011/5/30<br />WECO Lab http://www.weco.net<br />27<br />
  35. 35. Spatiotemporal dynamics of Alzheimer’s Disease<br />Three different models<br />Neuropathologicalstageing of Alzheimer-related changes<br />Describe global pattern of lesions caused by Alzheimer’s disease<br />Lesions: distribution of amyloid and neurofibrillary changes<br />Network Damage Model<br />Intentional attack on the node with highest degree<br />Observed in the brain affected by Alzheimer’s disease<br />Focus on fragments after attack<br />Treatment<br />Based on cholingeric hypothesis<br />Needs to find out the cholingeric pathways<br />A spatiotemporal model of Alzheimer’s Disease<br />A combination of three with temporal parameter added in<br />2011/5/30<br />WECO Lab http://www.weco.net<br />28<br />
  36. 36. Isocortical Areas<br />(including the belt fields and primary areas)<br />Stage III<br />Isocortex Association Area<br />Stage II<br />Basal Portion of Occipital Lobe<br />Basal Portion of Frontal Lobe<br />Stage I<br />Basal Portion of Limbic Lobe<br />Distribution Pattern of Amyloid Deposits<br />2011/5/30<br />WECO Lab http://www.weco.net<br />29<br />
  37. 37. Isorcortex<br />Stage V & VI<br />Limbic Area<br />(involve the entorhinal and transentorhinal layer Pre-α)<br />Stage III & IV<br />Transentorhinal Region<br />Stage I & II<br />Distribution Pattern of Neurofibrillary Tangles and Neuropil Threads<br />2011/5/30<br />WECO Lab http://www.weco.net<br />30<br />
  38. 38. Spatiotemporal dynamics of Alzheimer’s Disease<br />Three different models<br />Neuropathologicalstageing of Alzheimer-related changes<br />Describe global pattern of lesions caused by Alzheimer’s disease<br />Lesions: distribution of amyloid and neurofibrillary changes<br />Network Damage Model<br />Intentional attack on the node with highest degree<br />Observed in the brain affected by Alzheimer’s disease<br />Focus on fragments after attack<br />Treatment<br />Based on cholingeric hypothesis<br />Needs to find out the cholingeric pathways<br />A spatiotemporal model of Alzheimer’s Disease<br />A combination of three with temporal parameter added in<br />2011/5/30<br />WECO Lab http://www.weco.net<br />31<br />
  39. 39. Remove Hubs<br />Hub<br />A Cluster<br />Three Cluster<br />Network Damage Model<br />2011/5/30<br />WECO Lab http://www.weco.net<br />32<br />Where 𝑞𝑘 is the probability a node will be occupied,<br />𝜃(𝑥) is the is the Heaviside step function,<br />𝑘𝑚𝑎𝑥is the degree threshold,<br />𝑘 is the degree of a node<br /> <br />𝑞𝑘=𝜃𝑘𝑚𝑎𝑥−𝑘=1    𝑖𝑓    𝑘≤𝑘𝑚𝑎𝑥0    𝑖𝑓    𝑘>𝑘𝑚𝑎𝑥<br /> <br /><ul><li>It has been applied to some studies of Alzheimer’s disease</li></li></ul><li>Spatiotemporal dynamics of Alzheimer’s Disease<br />Three different models<br />Neuropathologicalstageing of Alzheimer-related changes<br />Describe global pattern of lesions caused by Alzheimer’s disease<br />Lesions: distribution of amyloid and neurofibrillary changes<br />Network Damage Model<br />Intentional attack on the node with highest degree<br />Observed in the brain affected by Alzheimer’s disease<br />Focus on fragments after attack<br />Treatment<br />Based on cholingeric hypothesis<br />Needs to find out the cholingeric pathways<br />A spatiotemporal model of Alzheimer’s Disease<br />A combination of three with temporal parameter added in<br />2011/5/30<br />WECO Lab http://www.weco.net<br />33<br />
  40. 40. 2011/5/30<br />WECO Lab http://www.weco.net<br />34<br />Neurochemical Changes in Alzheimer’s Disease<br />Postsynaptic Neuron<br />Presynaptic Neuron<br />Synapatic Cleft<br />Nerve Impulse<br />Acetyl-CoA<br />Vesicles<br />ChAT<br />Ca2+<br />ACh<br />𝑡𝑎𝑢⇌𝑡𝑎𝑢<br /> <br />p<br />APP<br />Choline<br />ACh Receptor <br />ChAT – Choline Acetyltransferase<br />ACh – Acetylcholine<br />AChE – Acetylcholinesterase<br />APP – Amyloid Precursor Protein<br />AChE Inhibitor<br />AChE<br />
  41. 41. 2011/5/30<br />WECO Lab http://www.weco.net<br />35<br />Cholinergic Pathways<br />neocortex<br />cingulate<br />retrosplenia<br />thalamus<br />visual area<br />Ch1<br />Ch2<br />Ch4<br />hippocampus<br />Ch3<br />olfactory bulb<br />amygdala<br />Ch1 – medial septum<br />Ch2 – vertical limb nucleus<br />Ch3 – horizontal limb nucleus<br />Ch4 – nucleus basalis<br />Ch5 – pedunculopontine nucleus<br />Ch6 – lateral dorsal tegmental nucleus<br />deep cerebellar nuclei<br />Ch5<br />Ch6<br />
  42. 42. Spatiotemporal dynamics of Alzheimer’s Disease<br />Three different models<br />Neuropathologicalstageing of Alzheimer-related changes<br />Describe global pattern of lesions caused by Alzheimer’s disease<br />Lesions: distribution of amyloid and neurofibrillary changes<br />Network Damage Model<br />Intentional attack on the node with highest degree<br />Observed in the brain affected by Alzheimer’s disease<br />Focus on fragments after attack<br />Treatment<br />Based on cholingeric hypothesis<br />Needs to find out the cholingeric pathways<br />A spatiotemporal model of Alzheimer’s Disease<br />A combination of three with temporal parameter added in<br />2011/5/30<br />WECO Lab http://www.weco.net<br />36<br />
  43. 43. Local View<br />Global View<br />5K<br />3.6<br />4K<br />2.0<br />1.2<br />1K<br />2011/5/30<br />WECO Lab http://www.weco.net<br />37<br />Global and Local Views of Alzheimer’s Brain<br />
  44. 44. 2011/5/30<br />WECO Lab http://www.weco.net<br />38<br />∀ node 𝑖 in the network at time 𝑡,<br /> <br />𝜃𝑘𝑡𝑎𝑟𝑔𝑒𝑡−𝑘𝑖=1     𝑖𝑓    𝑘𝑖≤𝑘𝑡𝑎𝑟𝑔𝑒𝑡0     𝑖𝑓    𝑘𝑖>𝑘𝑡𝑎𝑟𝑔𝑒𝑡,<br /> <br />𝑙𝑒𝑡 𝑘𝑡𝑎𝑟𝑔𝑒𝑡=𝑓𝑡=𝑘𝑚𝑎𝑥−𝑡−𝑡0𝑝<br /> <br />Where 𝜽(𝒙) is the Heaviside step function, <br />𝒌𝒕𝒂𝒓𝒈𝒆𝒕represents a threshold of degree, <br />𝒌𝒎𝒂𝒙 is the maximum degree in a local region,<br />𝒌𝒊is the degree of node 𝒊, <br />𝒕𝟎 is the start point of the simulation, <br />𝒑is a period of time that controls the duration of an attack<br /> <br />
  45. 45. 2011/5/30<br />WECO Lab http://www.weco.net<br />39<br />∀ target node in the network, the total decreased number of neurons at time 𝑡𝑛 is<br /> <br /> 𝒇𝒕=𝑵𝒕𝟎−𝑵𝒕𝒏 <br />           =𝒕𝟎𝒕𝒏𝑽𝒕𝒅𝒕<br />           =𝒕𝟎𝒕𝟏𝒗𝟏𝒅𝒕+𝒕𝟏𝒕𝟐𝒗𝟐𝒅𝒕+⋯+𝒕𝒏−𝟏𝒕𝒏𝒗𝒏𝒅𝒕<br />           =𝒗𝟏𝒕𝟏−𝒕𝟎+𝒗𝟐𝒕𝟐−𝒕𝟏+⋯+𝒗𝒏𝒕𝒏−𝒕𝒏−𝟏<br />           =𝒗𝒄𝒕𝟏−𝒕𝟎𝒂𝟏+𝒕𝟐−𝒕𝟏𝒂𝟐+⋯+𝒕𝒏−𝒕𝒏−𝟏𝒂𝒏<br />           =𝒗𝒄𝒊=𝟏𝒏𝒕𝒊−𝒕𝒊−𝟏𝒂𝒊<br /> <br />where𝑵𝒕is the decreased number of neurons,𝑽𝒕is the speed of neuron deaths,<br />𝒗𝒊 is the speed of neuron deaths at time 𝒕𝒊,𝒗𝒄 is the constant speed of neuron deaths,<br />𝒂𝒊 is the amount of acetylcholine at time 𝒕𝒊,<br /> <br />
  46. 46. 2011/5/30<br />WECO Lab http://www.weco.net<br />40<br />∀ edge 𝒆in the network with source node 𝑺 and target node 𝑻, <br />the weight of 𝒆 at time 𝒕𝒏is<br /> <br />𝑾𝒕𝒏=𝜷𝜶×𝑪(𝒕𝒏)𝟏𝟎𝟒×𝟏𝒍<br /> <br />where 𝜶,𝜷are coefficients to determine the ratio between 𝑪(𝒕𝒏)and 𝒍, <br />notice that 𝟎<𝜶,𝜷<𝟏,<br />𝑪(𝒕𝒏)is the number of connections that compose 𝒆 at time 𝒕𝒏,<br />𝒍is the length of 𝒆<br /> <br />𝑪𝒕𝒏=𝑵𝑺𝒕𝒏×𝟏𝟎𝟒×𝒚𝒙+𝒚×𝑵𝑻(𝒕𝒏)𝒊=𝟎𝒚𝑵𝑻𝒊(𝒕𝒏)                    𝒊𝒇    𝒏=𝟎𝑪𝒕𝒏−𝟏×𝟏−∆𝒏𝑺𝑵𝑺𝒕𝒏−𝟏    𝒊𝒇    ∆𝒏𝑺≥∆𝒏𝑻𝟏−∆𝒏𝑻𝑵𝑻𝒕𝒏−𝟏    𝒊𝒇    ∆𝒏𝑺<∆𝒏𝑻        𝒊𝒇    𝒏>𝟎<br /> <br />where 𝒙and 𝒚are the number of inlinks and outlinks respectively,<br />∆𝒏𝑺and ∆𝒏𝑻are the decreased number of 𝑺and 𝑻respectively from<br />𝒕𝒏−𝟏 to 𝒕𝒏<br /> <br />
  47. 47. 2011/5/30<br />WECO Lab http://www.weco.net<br />41<br />Steps of Brain Network Simulation of Alzheimer’s Disease<br />Assume that 𝜶,𝜷, 𝒍are all equal to 1, 𝒗𝒄 is 2 per unit time, and 𝒂 is a factor of 2, <br />then the dynamics of weights are as follow:<br /> <br />5<br />3<br />2<br />1.875<br />1.125<br />0.375<br />ACh<br />0.33<br />0.33<br />0.13<br />0.625<br />0.375<br />0.25<br />1.66<br />1<br />0.33<br />3<br />1<br />3<br />1<br />1<br />1<br />0.33<br />0.33<br />0.11<br />t = 0<br />t = 1<br />t = 2<br />
  48. 48. Demo<br />2011/5/30<br />WECO Lab http://www.weco.net<br />42<br />
  49. 49. Conclusion<br />Brain simulation is the trend in the future of brain science studies<br />Try to design a brain network simulator<br />Layered architecture inspired by network comparison<br />Brain components<br />Workflow<br />Development approach<br />Case-based incremental delivery<br />A spatiotemporal model of Alzheimer’s disease<br />A prototype of brain network simulator<br />2011/5/30<br />WECO Lab http://www.weco.net<br />43<br />
  50. 50. Future Work<br />Brain network simulator development<br />Brain components refinement<br />Input data and data preprocessing<br />Network analysis<br />Distributed computing<br />Evolved brain network simulator<br />Add more cases into the brain network simulator<br />Ex: research result or experiment data of sleep<br />Usage<br />Research<br />Diagnosis<br />Personal healthcare<br />2011/5/30<br />WECO Lab http://www.weco.net<br />44<br />
  51. 51. Q&A<br />2011/5/30<br />WECO Lab http://www.weco.net<br />45<br />
  52. 52. Thanks For Listening!<br />2011/5/30<br />WECO Lab http://www.weco.net<br />46<br />

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