Early stages of production Oller (1980) and Stark (1980)

Within these stages are considerable overlap.

I. Phonation (0-1 mos.)

II. Goo or Cooing (2-4 months)

III. Expansion stage; vocal play (4-6 mos.)

IV. Canonical and reduplicated babbling (6-8-10 mos.)

reduplicated babbling; Variegated babbling-

V. Jargon Stage

Vocoid and Contoids- nonphonemic speech sound productions