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SENSORY PRIMACY IN THE INFANT'S DISCRIMINATION OFTHE MOTHER Colleen Smitherman.

It has been suggested that attachment depends onI

the infant being able to discriminate the mother Ifrom other individuals. It is often assumed that I

the infant first does this using visual information. 1Infants 12 weeks old have been found capable ofdiscriminating their mother's face, but otherstudies suggest that discrimination of the mother'svoice may occur even earlier. This study comparedauditory and visual discrimination of the mother ininfants from I1to 28 weeks old using one paradig~.

After a pretest, 36 infants were habituated tocriterion to their mother's projected photographaccompanied by her recorded voice. Another 36infants were .habituated to an unfamiliar female.Test tr~als were given where the .voice changed, theface changed, both changed, or nothing changed. Aposttest followed.

There were no significant effects for sex orcondition, but there was a significant interactionbetween age and test trial. Eleven-week-old· infantssignificantly increased fixation time only in trialswhere the voice changed. Twenty-eight-week-oldinfants increased fixation time only in trials wherethe face changed.

These results suggest that ll-week-old infantsmay attend more to auditory than visual informationin discriminating the mother from other socialobjects. .BY 28 weeks, infants had made a shift insensory primacy towards increasing attention tovisual information and decreasing attention toauditory information.