Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Family Consumer Human Development

Committee Chair(s)

Lori A. Roggman


Lori A. Roggman


Kandy Baumgardner


Tim Gilbertson


Ann Austin


Research on parenting is increasingly being studied from a biological perspective. An understanding of the biological mechanisms leading to individual differences in maternal behaviors can help direct research toward more focused intervention resulting in closer mother-infant attachment relationships, and therefore, positive child outcomes. This research was a preliminary study that tested mothers' ability to taste a harmless chemical, 6-n-propylthiouracil (PROP), in relation to their responses to a questionnaire about the emotional investment they experience towards their infant. Although research attempting to relate these two variables together has not been carried out before, individual studies show potential links between these two.

The model underlying this research is that the hormones involved in parent investment, such as oxytocin and estrogen, are mediated on a cellular level by second messenger systems which vary in individuals, and that the ability to taste PROP, a chemical that some people can taste and others can not, has genetic connections to this second messenger system. Although the lack of previous research limited strong predictions, it was expected that tasters of PROP would possess a hormonal milieu that would relate to more invested parenting, compared to non-tasters.

This study tested 220 low-income mothers of one-year-old infants enrolled in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) and Early Head Start (EHS) program for their ability to taste PROP, and correlated their taste sensitivity with parent investment as measured by a questionnaire. Additional questionnaires assessed adult attachment, breastfeeding, and close physical contact as possible mediators and moderators in the association between parent investment and PROP taste sensitivity.

Findings were statistically significant, although in the opposite direction than hypothesized. Non-tasters of PROP, rather than tasters, had higher overall parent investment responses than tasters. Non-tasters also rated higher than tasters in secure adult attachment attitudes. Close physical contact related to increased parent investment. There was no relationship between taste sensitivity and duration of breast feeding or between taste sensitivity and close physical contact.