Case studies of isolated children have supported the critical period hypothesis. These children who are exposed to language later in life, have shown extreme deficits in phonology, morphology and syntax. The best known is the case of Genie, a girl who was locked in a room where she had minimal human contact, particularly with her mother. She was punished by her father if she was to make any noises or sounds. She was discovered at the age of 13 and placed in a normal linguistic environment. When she first brought to the hospital, she did not acquire any language. Although she acquired some English after puberty, her phonology was abnormal and she had limited control over her syntax and morphology.
Fromkin et al. (1974) tested Genie on a dichotic
Fromkin et al. (1974) tested Genie on a dichotic