Here are several links to bibliographies about the relationship between breastfeeding and cognitive development:

http://www.flca.info/HTMLobj-152/Bg___Cognitive.pdf
http://www.kellymom.com/bf/bfextended/ebf-refs.html#Intelligence
http://www.kellymom.com/bf/start/prepare/bf-benefits.html#Intelligence

That may at least give you a start at finding the information you are looking for!

Warmly,
Michelle Roth, BA, LCCE, CIMI, La Leche League Leader, mother of 4

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