Attentional modulation of feature selectivity in area V4 James Mazer Department of Neurobiology Yale School of Medicine

Attentional modulation of feature selectivity in area V4 James Mazer Department of Neurobiology Yale School of Medicine

What is feature attention?

• Feature-based attention: attention directed towards a particular value along some stimulus dimension

• in contrast to...

• attention to a particular region of space (space-based)
• attention to a particular visual “channel” or feature dimension

Why study feature attention?

• natural visual environments are cluttered

• during natural vision we often know what we want, even when we don’t know where it is

• feature attention, like spatial attention, can provide some resolution of limited neural bandwidth or capacity problems

How do we study feature attention?

Extrastriate area V4

Salience maps & visual search

Salience maps & visual search

Feeviewing visual search task

Feeviewing visual search task

Freeviewing visual search behavior

Modeling attentional effects

Freeviewing reverse correlation

Modeling attentional effects

Freeviewing reverse correlation

Tuning shift: matched filter

Tuning shift: matched filter

Summary

• feature attention can alter (1) mean rate, (2) gain and (3) preferred stimuli in V4

• baseline, gain and selectivity modulations occur in all possible combinations

• preference changes could facilitate target detection during visual search (but it’s not a simple matched filter).

• maximal tuning modulation occurs in neurons with broadest orientation tuning

Acknowledgements