One of the pioneers in the field of developmental cognitive neuroscience, Diamond researches how executive functions are affected by biological and environmental factors, especially in children.

[12] Although officially a PhD candidate in Psychology, she spent her first four years of graduate school working primarily in anthropology and sociology.

[12] Having given up her initial thesis topic, she returned to a question that Jerome Kagan had posed in Diamond's first year in graduate school: "If infants all over the world show the same cognitive changes at roughly the same time, those changes cannot be due entirely to learning or experience, because their experiences are too diverse; there must be a maturational component; what might that maturational component be?

[12] Diamond hypothesized that maturational changes in the brain's prefrontal cortex made possible the impressive cognitive advances seen between 6 and 12 months of age.

[12] Diamond learned from books on her own and was granted permission to add Nelson Butters from the Boston VA (who had published widely on the anatomy and functions of prefrontal cortex) to her thesis committee.

[12] To get hard evidence on the brain to support her hypothesis, Diamond went to Yale University School of Medicine to work with Patricia Goldman-Rakic.

The conference and resulting book served to jumpstart many research collaborations and the nascent field of developmental cognitive neuroscience.

[36] She has spoken in North America and abroad (including in Argentina, Australia, Austria, Belgium, Brazil, Bulgaria, Chile, Czechoslovakia, Denmark, Ecuador, France, Germany, India, Indonesia [Bali & Java], Ireland, Israel, Italy, Mexico, the Netherlands, New Zealand, Peru, Poland, Portugal, Russia, South Africa, Spain, Sweden, Switzerland, Thailand, and the UK [England, Scotland, and Wales]).