Month: April 2016

New preprint: letter distortions and visual crowding

A preprint of our manuscript “Detecting distortions of peripherally-presented letter stimuli under crowded conditions” is now available on biorXiv.

The manuscript is submitted for publication, but we’d really appreciate comments from anyone who’s interested. Just send me an email at with any thoughts, suggestions, abuse, etc!

Quick link: QuestIntuition

My friend Daniel Saunders recently released a neat little graphical toolbox for Matlab called QuestIntuition that allows you to play around with the QUEST procedure for adaptive sampling of psychometric thresholds. This will be a good resource for students learning how QUEST works.

Some questions :

  1. What happens if the initial guess is way off? How many trials does QUEST need to recover?
  2. What happens if the assumed slope is way off?
  3. What happens if the upper asymptote of the psychometric function is lower than the threshold QUEST is trying to find (I saw this in a paper I reviewed once)? Does it still produce reasonable samples?

Check it out!