University of Cambridge > Talks.cam > Craik Club > Is the code in ferret V1 a 'sparse code'?

  Browse A-Z

Log in

Googledetails Microsoftdetails

🔐 Log In

Information on

Subscribing to talksdetails Finding a talkdetails Adding a talkdetails Disseminating talksdetails Help and Documentationdetails

ℹ️ Information

Is the code in ferret V1 a 'sparse code'?

Download to your calendar using vCal

If you have a question about this talk, please contact Cordula Becker .

It has been proposed that the primary visual cortex provides a “sparse code” for the information in natural scenes. It has been difficult to pin down quite what a sparse code would look like! One measure is “life-time sparseness”: how few natural scenes does a given neuron respond to. We investigated how neurons in ferret V1 responded to flashed presentations of digitised photos of natural scenes. Some neurons showed very sparse responses: i.e. they responded to very few photos. The degree of sparseness was correlated with whether the neurons were simple or complex, with the sharpness of their tuning for sinewave gratings and with their general responsivity to gratings. In a sparse code, a neuron would respond weakly to most stimuli but would respond well to a few, giving a leptokurtic response distribution. In V1, response variance increases with increasing response. If a response distribution is replotted against equally-discriminable response steps, the distribution becomes much less kurtotic!

This talk is part of the Craik Club series.

This talk is included in these lists:

Note that ex-directory lists are not shown.

Other lists

andrew caine CCDC, 12 Union Road, Cambridge, CB2 1EZ Kapitza Seminar Room, Room 16 Kapitza Building, Cavendish Laboratory

Other talks

Tissue-scale communication in cancer development Title to be confirmed Welcome Reception and Poster Session Title to be confirmed Group Work Dr Dinis Calado, Senior Group Leader, Immunity and Cancer Laboratory, the Francis Crick Institute
 

© 2006-2025 Talks.cam, University of Cambridge. Contact Us | Help and Documentation | Privacy and Publicity