1. What is (computational) neuroscience? Neuroscience is the scientific study of the nervous system. It is a an interdisciplinary science that involves biology, chemistry, computer science, engineering, linguistics, mathematics, medicine, physics, psychology and even philosophy. Different approaches are used to study the molecular, cellular, developmental, structural, functional, evolutionary, computational, and medical aspects of the nervous system. Golgi – staining Ramon y Cajal -- anatomy Nobel Prize: Selverston lab, 1960s Neural circuit for chewing In lobster. Wu lab, 2004 Spiral waves in cortex (diam: 3-4 mm) fMRI, 1990s BOLD signal , brain areas John Rinzel (NYU), Kiev, 2011
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5. From McIntyre working group, 2006. 3-D reconstruction + DBS electrode placement + simulation of electric fields
6. Temporal pattern of pulse delivery … see P Tass, use of nonlinear dynamical systems
7. Computational Neuroscience What “computations” are done by a neural system? How are they done? WHAT? Feature detectors, eg visual system. Coincidence detection for sound localization. Memory storage. Code: firing rate, spike timing. Statistics of spike trains Information theory Decision theory Descriptive models HOW? Molecular & biophysical mechanisms at cell & synaptic levels – firing properties, coupling. Subcircuits. System level.
8. Computational Neuroscience What “computations” are done by a neural system? How are they done? WHAT? Feature detectors, eg visual system. (Hubel & Wiesel & Sperry: Nobel, 1981) Coincidence detection for sound localization. Memory storage. Code: firing rate, spike timing. Statistics of spike trains Information theory Decision theory Descriptive models HOW? Molecular & biophysical mechanisms at cell & synaptic levels – firing properties, coupling. Subcircuits. System level.
9. In vivo data from the barn owl shows auditory brain stem (NL) neurons encode ITD for sound localization A B C D E PLACE CODE OUTPUTS DELAY LINE INPUTS DELAY LINE INPUTS C 5 left ear leads right ear leads INTERAURAL TIME DIFFERENCE (µsec) 100 50 0 4409 Hz 0 -300 -150 150 300 -30 µsec % MAXIMUM RESPONSE A neural computation by single cell… but how? And soooo fast, when spikes and synaptic potentials are 1 ms time scale…
10. Dynamics of Excitability and Repetitive Activity Auditory brain stem neurons fire phasically, not to slow inputs. w/ Svirskis et al, J Neurosci 2002
11. Neuroscience -- a field with foundational understanding based on mathematical & computational approaches Nobel Prize, 1959 – shared with JC Eccles Wilfrid Rall (starting 1950s) developed ‘cable theory’ for dendrites
12. Computational Neuroscience What “computations” are done by a neural system? How are they done? WHAT? Feature detectors, eg visual system. Coincidence detection for sound localization. Memory storage. Code: firing rate, spike timing. Statistics of spike trains Information theory Decision theory Descriptive models HOW? Molecular & biophysical mechanisms at cell & synaptic levels – firing properties, coupling. Subcircuits. System level.