Bradley Voytek - Cognitive Networks

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In the blink of an eye—less than half a second—dynamic neuronal networks in our brains process, maintain, and act upon an abundance of information. In my research I seek to construct an understanding, from a network perspective, of cognition built upon first principles of neurophysiology and computational models. To do this I incorporate a variety of methods and tools in my research, including intracranial electrophysiological recordings from humans, scalp electroencephalography from healthy younger and older adults, behavioral and neuroimaging studies involving patients with focal brain lesions, data-mining of large-scale databases, and brain-computer interfacing. Specifically my research program aims to answer three questions: 1) What role does the prefrontal cortex play in shaping and coordinating network activity during complex cognition and executive functioning? 2) Under what circumstances is this network altered or disrupted and what are the consequences of such disruption? And, 3) What are the principles that allow for network communication in noisy internal and external environments? My research addresses these questions across multiple scales ranging from basic neurophysiology to population-wide analyses of cognitive data collected from more than 400,000 participants. My goal is to take cognitive science outside of the laboratory and "into the wild" using distributed data collection and large-scale data analysis to help bridge psychology and basic physiology.

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Bradley Voytek - Cognitive Networks

  1. 1. Cognitive Networks: From Neural to National AssembliesBradley Voytek, PhDUCSF Department of Neurologybradley.voytek@gmail.comhttp://ketyov.com
  2. 2. Frontal Cognitive Networks1. Frontal-dependent working memory networks2. Decision making and frontal network dynamics3. Neurophysiology of executive function in aging
  3. 3. Voytek & Voytek, J Neurosci Methods 2012
  4. 4. Prefrontal Working Memory Network1. Prefrontal lesions impair “top-down” control2. Dynamic network reorganization3. Rapid information (re)routing
  5. 5. Visual Working Memory Taskc.f.: Vogel & Machizawa, Nature 2004
  6. 6. Brain and Behavior - Causal RelationsSource: Damasio et al., Science 1994
  7. 7. Frontal Lobe LesionsSource: Voytek & Knight, PNAS 2010
  8. 8. Lateralized Presentation Non-match Match (1080-2580 ms) y s) la 0 m de 08 + test 1 80- (1 + + (0-180 ms) memory e + tim Ipsilesional ContralesionalSource: Voytek & Knight, PNAS 2010
  9. 9. Working Memory Deficits Non-match Match 3.0 ** ipsi- (1080-2580 ms) y s) la 0 m de 08 + test 0- 1 contra- accuracy (d) 8 (1 accuracy (d) + + (0-180 ms) memory e + tim 2.5 * * * 2.0 Control PFC BG Ipsilesional Contralesional L / RSource: Voytek & Knight, PNAS 2010
  10. 10. EEG
  11. 11. Top-Down Network Dysfunction Controls Patients 0.6 µV 0.4 µV -0.6 µV -0.4 µV Posterior Hemispheric Posterior Hemispheric Alpha Differences Alpha Differences P = 0.15 P = 0.045Source: Voytek & Knight, PNAS 2010
  12. 12. Visual Working Memory MaintenanceSource: Vogel & Machizawa, Nature 2004
  13. 13. Ipsilesional Contralesional -4 * -4 CDA amplitude (μV) CDA amplitude (μV) -2 -2PFC 0 0 2 2 300 900 300 900 -4 -4 CDA amplitude (μV) CDA amplitude (μV) -2 -2BG 0 0 2 2 stimulus 300 900 stimulus 300 900 onset time (ms) onset time (ms)
  14. 14. Why aren’t Deficits Complete?Source: Voytek, et al., Neuron 2010
  15. 15. Dynamic Network CompensationSource: Voytek, et al., Neuron 2010 c.f.: Voytek, et al., PLoS ONE 2012
  16. 16. Prefrontal Working Memory Network1. Prefrontal lesions impair “top-down” control2. Dynamic network reorganization3. Rapid information (re)routing
  17. 17. Frontal Cortical Network Coordination1. Frontal networks in cognitive control2. Frontal networks are dynamic3. Oscillatory coupling subserves network activity
  18. 18. Electrocorticography
  19. 19. ElectrocorticographyWARNINGGRAPHIC
  20. 20. Electrocorticography
  21. 21. Why ECoG?Source: Voytek, et al., J Cogn Neurosci 2010
  22. 22. Frequency Decomposition
  23. 23. Neurophysiology of Communicationc.f.: work by Miller EK; Fries; Singer; etc.
  24. 24. Coherence
  25. 25. Coherence
  26. 26. Communication through Coherencesource: Fries, Trends Cogn Sci 2005 c.f.: Voytek, et al., NeuroImage 2012
  27. 27. Spectral TopographySource: Voytek, et al., Front Hum Neurosci 2010
  28. 28. Frontal Theta/Gamma CouplingSource: Voytek, et al., Front Hum Neurosci 2010 c.f.: Canolty, et al., Science 2006
  29. 29. Visual Alpha/Gamma CouplingSource: Voytek, et al., Front Hum Neurosci 2010
  30. 30. Watrous et al., Nat Neurosci 2013
  31. 31. Source: Voytek, et al., in revision
  32. 32. Rostro-caudal Frontal OrganizationSource: Badre & D’Esposito, Nat Rev Neurosci 2009
  33. 33. Phase/Amplitude Coupling NetworksSource: Voytek, et al., in revision
  34. 34. PFC Phase/Amplitude CouplingSource: Voytek, et al., in revision
  35. 35. Phase/Amplitude Coupling NetworksSource: Voytek, et al., in revision
  36. 36. “Cognitive” Brain Computer InterfaceSource: Voytek, in progress c.f.: work by Ro; Thut; Herrmann; etc.
  37. 37. Frontal Network Coordination1. Frontal networks in cognitive control2. Frontal networks are dynamic3. Oscillatory coupling subserves network activity
  38. 38. Aging and Cognition1. Behavioral noise increases in aging2. Neural noise increases in aging3. Altered network communication in aging
  39. 39. Age and Response TimeSource: Voytek & Gazzaley, in preparation
  40. 40. Theories of Cognitive Aging Frontal Atrophy Neural NoiseSource: Andrews-Hanna et al., Neuron 2007
  41. 41. Neural Noise HypothesisSource: Voytek, et al., under review
  42. 42. Aging Increases Neural NoiseSource: Voytek, et al., under review
  43. 43. Aging Increases Neural NoiseSource: Voytek, et al., under review
  44. 44. Aging Decreases PACSource: Voytek, et al., under review
  45. 45. Aging and Cognition1. Behavioral noise increases in aging2. Neural noise increases in aging3. Altered network communication in aging
  46. 46. Where We Are Now1. Frontal networks critical (causal) in cognition2. Rapid network plasticity3. Oscillatory mechanisms subserve frontal control4. Frontal involvement in aging and neural noise
  47. 47. Age and Response TimeSource: Voytek & Gazzaley, in preparation
  48. 48. Flanker InterferenceSource: lumosity.com
  49. 49. Age, Distractibility, & PracticeSource: Voytek & Gazzaley, in preparation
  50. 50. n-back Working MemorySource: lumosity.com
  51. 51. 50 States 267,776 participants 16,288 participants IQSource: Voytek & Gazzaley, submitted
  52. 52. 51 Countries 109,907 participants 9,985 participants IQSource: Voytek & Gazzaley, submitted
  53. 53. Future Directions
  54. 54. SupportNational Institute of Neurological Disorders and Stroke NS021135National Institute of General Medical Sciences Institutional Research and Career Development Award (IRACDA)UCSF Information Technology Innovation AwardThe Feldman Family FoundationUniversity of California Presidents Postdoctoral Fellowship ProgramSociety for Neuroscience - Neuroscience Scholars Program
  55. 55. Cognitive Networks: From Neural to National AssembliesBradley Voytek, PhDUCSF Department of Neurologybradley.voytek@gmail.comhttp://ketyov.com

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