My research over the past ten years shows each of these views are incorrect.
Instead, babies form concepts from early in life. Although primitive and
not fleshed out, the first concepts are abstract and form the foundation
of the adult conceptual system. The "new" infant is useful in understanding
the continuity of development and illuminates not only the course of growth
of the conceptual system but also its decline in semantic dementia and
related brain disorders.
Jean Mandler is professor in UC San Diego's Department of Cognitive Science.
Mandler, Jean M. Development of categorisation: Perceptual and conceptual categories. IN: Infant development: Recent advances. Gavin Bremner, Alan Slater, George Butterworth, Eds. Hove, England: Psychology Press/Erlbaum, 1997. p. 163-189.
Mandler, Jean M. Preverbal representation and language. IN: Language and space. Language, speech, and communication. Paul Bloom, Mary A. Peterson, Lynn Nadel, Merrill F. Garrett, Eds. Cambridge, MA: MIT Press, 1996. p. 365-384.
Mandler, Jean M.; McDonough, Laraine. Long-term recall of event sequences in infancy. Special Issue: Early memory. Journal of Experimental Child Psychology, 1995 Jun, v59 (n3):457-474.
Gardner, Howard; Mandler, Jean M.; Kosslyn, Stephen M. Developmental
theories and neurocognition. IN: The science of the mind: 2001
and beyond. Robert L. Solso, Dominic W. Massaro, Eds. New York,
NY: Oxford University Press, 1995. p. 65-106.