Abstract
Three
pigeons were trained to remember arrays of 2–6 colored squares and
detect which of two squares had changed color to test their visual
short-term memory. Procedures (e.g., stimuli, displays, viewing times,
delays) were similar to those used to test monkeys and humans. Following
extensive training, pigeons performed slightly better than similarly
trained monkeys, but both animal species were considerably less accurate
than humans with the same array sizes (2, 4 and 6 items). Pigeons and
monkeys showed calculated memory capacities of one item or less, whereas
humans showed a memory capacity of 2.5 items. Despite the differences
in calculated memory capacities, the pigeons’ memory results, like those
from monkeys and humans, were all well characterized by an inverse
power-law function fit to d’ values for the five display sizes.
This characterization provides a simple, straightforward summary of the
fundamental processing of visual short-term memory (how visual
short-term memory declines with memory load) that emphasizes species
similarities based upon similar functional relationships. By closely
matching pigeon testing parameters to those of monkeys and humans, these
similar functional relationships suggest similar underlying processes
of visual short-term memory in pigeons, monkeys and humans.
Keywords
- Change detection;
- Visual short-term memory;
- Visual working memory;
- Pigeons;
- Monkeys;
- Humans
Copyright © 2015 Elsevier B.V. All rights reserved.
