1 / 10

Cricket cercal system: population coding and linear algebra I

Ila Fiete Quantitative Methods in Neuroscience NEU 366M – Spring 2014 University of Texas at Austin. Cricket cercal system: population coding and linear algebra I. Cricket cercal system for wind detection. spiky antenna-like “cerci”. ~ 1 cm long each ~750 hairs/cercus

barbara-snider
Download Presentation

Cricket cercal system: population coding and linear algebra I

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Ila Fiete Quantitative Methods in Neuroscience NEU 366M – Spring 2014 University of Texas at Austin Cricket cercal system: population coding and linear algebra I

  2. Cricket cercal system for wind detection spiky antenna-like “cerci” • ~ 1 cm long each • ~750 hairs/cercus • non-bending hair in socket with unidirectional “hinge” • single mechanosensory receptor neuron wraps socket • receptor converts hair motion into voltage change • and spiking activity. Gwen Jacobs et al., J. ExpBiol 2008 Gabbiani & Cox, Ch.12

  3. Cricket cercal system for wind detection • Cricket nervous system: • Chain of ganglion nodes (cell bodies) connected • nerve bundles (axon/dendrite cables). • Last node: where cercal receptor/interneuron • circuit resides. Dark brown, light brown, cyan: receptor neurons. Purple: interneuron. Massive dimensionality reduction: 1500 receptor neurons  20 projecting interneurons. Gwen Jacobs et al., J. ExpBiol 2008 Gabbiani & Cox, Ch.12

  4. Tuning of identified cercal interneuron (10-2A) Beautiful “cosine tuning” shape:

  5. Group of identified interneurons Wind orientation tuning curves represent all four cardinal orientations.

  6. Simultaneous wind speed (intensity) tuning Linear increase in firing rate with logof windspeed.

  7. Interneuron does NOT specify wind-direction: many angles to one response Tuning curve not monotonic: one rate corresponds to more than one angle.

  8. Interneuron does NOT specify wind-direction: one angle to many responses Wind-speed modulation Tuning curve is multi-valued: one wind angle can drive various rates (depending on speed).

  9. Population coding: collection of neurons together code for variable • Wind orientation tuning curves represent all four cardinal orientations. • Cercal interneurons are basis vectors for the 2-dimensional space of horizontal wind directions and speeds.

  10. How to understand and decode the population code?

More Related