The Capacity of Visual Short-Term Memory is Set Both by Visual Information Load and by Number of Objects

  title={The Capacity of Visual Short-Term Memory is Set Both by Visual Information Load and by Number of Objects},
  author={George A. Alvarez and Patrick Cavanagh},
  journal={Psychological Science},
  pages={106 - 111}
Previous research has suggested that visual short-term memory has a fixed capacity of about four objects. However, we found that capacity varied substantially across the five stimulus classes we examined, ranging from 1.6 for shaded cubes to 4.4 for colors (estimated using a change detection task). We also estimated the information load per item in each class, using visual search rate. The changes we measured in memory capacity across classes were almost exactly mirrored by changes in the… 

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