Related Experiment Video
Updated: Aug 13, 2026
06:14
A Method for Investigating Change Blindness in Pigeons (Columba Livia)
Published on: September 7, 2018
Abstract:
Many partially sighted children use the mouth, lips, and tongue as an aid in identifying objects-this has been termed discriminatory pica. Investigation of a case of lead poisoning in a pupil at a residential school for the blind led to the discovery of others with asymptomatic lead poisoning, all of whom had the same habit.All the children recovered without treatment when they abandoned their habit of discrimination by use of the mouth. Authorities responsible for schools for the blind should be aware of this risk.
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