Parrot Cognition: Symbolic Understanding of "Same" and "Different"

This study investigated whether a parrot could use vocal labels to demonstrate a symbolic understanding of the concepts "same" and "different."

Method

Participants

The subject was an African Grey parrot named Alex.

Procedure

Researchers used the model-rival technique to train Alex. This involved:

• Teaching Alex to vocally label objects based on color, shape, and material.
• Presenting Alex with pairs of objects and asking "What's same?" or "What's different?"
• Rewarding Alex for correct vocalizations.

Training and Testing

• Training sessions occurred 2-4 times per week, lasting 5 minutes to 1 hour.
• Objects varied in color (red, green, blue), shape (triangular, square), and material (rawhide, wood).
• Secondary trainers, unfamiliar to Alex, conducted trials to minimize cueing effects.
• Testing took place over 26 months, with "same/different" questions integrated into other testing sessions.
• To ensure novelty, the same objects were never presented twice during testing.
• Incorrect responses resulted in object removal and a verbal "NO!" from the examiner.

Results

Familiar Objects

• Alex responded correctly in 99 out of 129 trials (76.6%).
• First-trial accuracy was 69.7% (69 out of 99).

Novel Objects

• Alex achieved 85% accuracy (96 out of 113) on novel objects.
• First-trial accuracy for novel objects was 82% (79 out of 96).

Probes

• Alex scored 90% (55 out of 61) on probe trials.
• First-trial accuracy on probes was 89% (49 out of 55).

Conclusions

This study provides evidence that parrots have the potential to:

• Comprehend the symbolic concepts of "same" and "different."
• Learn and respond to verbal questions with categorical labels.