Confused by this anomaly, Gould assumed she must have been making some simple experimental error, and she went to the Rockefeller library, hoping she could find an explanation as to what she was doing wrong. She ended up looking through numerous papers in the Rockefeller stacks. Several 1962 papers revealed the research at MIT by Joseph Altman claiming that adult rats, cats, and guinea pigs all formed new neurons. Altman’s results had been at first ridiculed, then ignored, and quickly forgotten in favor of Pasko Rakic's findings.