Grapheme–phoneme correspondence learning in parrots

Symbolic representation acquisition is the complex cognitive process consisting of learning to use a symbol to stand for something else. A variety of non-human animals can engage in symbolic representation learning. One particularly complex form of symbol representation is the associations between orthographic symbols and speech sounds, known as grapheme–phoneme correspondence. To date, there has been little evidence that animals can learn this form of symbolic representation. Here, we evaluated whether an Umbrella cockatoo (Cacatua alba) can learn letter-speech correspondence using English words. The bird-participant was trained with phonics instruction and then tested on pairs of index cards while the experimenter spoke the word. The words were unknown to the bird and the experimenter was blinded to the correct card position. The cockatoo’s accuracy (M = 71%) was statistically significant. Further, we found a strong correlation between the bird’s word-identification success and the number of overlapping letters between words, where the more overlapping letters between words, the more likely the cockatoo answered incorrectly. Our results strongly suggest that parrots may have the ability to learn grapheme–phoneme correspondences.