Effects of mother and infant hearing status on interactions at twelve and eighteen months.

Eighty mother-infant dyads, evenly distributed among the four possible hearing status combinations, were videotaped during free play when infants were 12 months old and again when they were 18 months old. Pairs of trained observers evaluated interactive behaviors for mothers, infants, and dyads. At time 1, hearing mothers and deaf infants ranked lowest, hearing mothers and hearing infants ranked highest, with the two deaf-mother groups intermediate. At time 2, deaf mothers and hearing infants received more negative rankings, leading to concern for the effect of mismatched hearing status regardless of the functional capabilities of mothers and infants to communicate in a mutually comprehensible mode. Discussion focuses on possible explanations for the negative influence of hearing status differences.