Publication Date


Document Type


First Advisor

Sie, Georgiana W.

Degree Name

M.S. (Master of Science)

Legacy Department

Department of Home Economics


Infant psychology


Research in the fields of child development and human psychology has shown that manipulation of certain aspects of a child's environment appears to have a measurable effect on his vocalizations, particularly after the third month of postnatal life. The generic question of the present study is: "Can one influence the frequency of vocalization of four-month-old infants by brief daily periods of specific vocal and visual stimulation?" Vocalization frequency was tabulated from pre-and post-experimental recordings of the total sample of ten infants, and from additional weekly five-minute sample recordings of the four infants of the experimental group. Intervention consisted of daily fifteen-minute periods of vocal and visual stimulation conducted by the researcher for five consecutive weeks in the infants' homes. The major hypothesis underlying the study was supported, i.e. the difference of the change in vocalization frequency between the experimental group and the control group was significant beyond the .05 level. Additionally, infant sex appeared to be an influential variable! the frequency of vocalizations increased for both males and females of the experimental group and for females of the control group, whereas the recorded vocalization frequency of the control group males decreased significantly (at the .035 level) during the same period.


Includes bibliographical references.||Includes illustrations.


x, 104 pages




Northern Illinois University

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