Animal Information Processing

Comparative psychologists have been very creative in recent decades. Many of their experiments use conditioning techniques to show that animals perform sophisticated information processing, with results similar to humans.

How have comparative psychologists been creative in recent decades? What are the two alternatives, when animals are trained to do "clever" things?

Is this the return of the "similarity assumption" of Romanes? Not necessarily. There are always two possibilities when non-human animals perform in a way resembling humans:

1. The animal is carrying out the same information processing as humans.

2. The animal is performing the same task in a different way.

Either alternative is interesting to psychologists. The first possibility, that a common mechanism underlies the behavior of different species, might point us toward fundamental or "primitive" processes widely shared in the animal kingdom. Complex cognitive activity is composed of many simpler processes, and surely humans and different species share some of those.

The second possibility, that different species (or different individuals) perform a task in different ways, also presents an interesting challenge. Scientists can compare the different solutions for clues to their advantages and disadvantages. For example, one solution might involve only a few neurons; therefore it might be very efficient. However, the efficient solution may be limited in other ways.

Here are some examples of comparative research showing that different species can perform some of the same information processing tasks as humans, whether or not they do it in the same exact way.

What is a surprising finding involving chinchillas?

—Kuhl and Miller (1975) showed that a chinchilla was just as good as humans at discriminating complex human speech ability once thought to be a unique evolutionary adaptation of humans.

—Brannon and Terrace (1998) showed that chimps could learn to count from 1 to 9 and to identify pictures that contained 1 to 9 different objects.

—Blough (1962) showed that pigeons saw letters of the alphabet much like humans. The pigeons produced a "confusion matrix" (tendency to mistake one letter for another) similar to humans.

The Muller-Lyer illusion

How did Geiger and Paggio study a housefly's response to the Muller-Lyer illusion?

—Geiger and Paggio (1975) showed that common houseflies are fooled by the Muller-Lyer illusion, perceiving the midpart of the bottom arrow as longer than the midpart of the top arrow.

—Bottle-nosed dolphins were shown to have a memory for lists of sounds similar to that of humans (Thompson & Herman, 1977).

—Goldfish were shown to see the "same" color even when spectral composition is radically altered, just like humans (Ingle, 1985).

—Tree swallows follow a logical "game-playing" or "decision-making" pattern called Tit-for-Tat (Lombardo, 1985).

—Cats have the same P300 component of the EEG, equated with meaningful interpretation of stimuli, as do humans (Wilder, 1981). So do monkeys (Arthur & Starr, 1984).

—Octopi are capable of observational learning. If allowed to watch another octopus that has been trained to pick one of two targets, the observer will pick the same target (Fiorito and Scotto, 1992).

And the list goes on. Many laboratory tests of human cognitive abilities can be adapted to non-human animals, with suitable ingenuity. The result is often the discovery that non-human animals perform similarly to humans.

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Copyright © 2007 Russ Dewey