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Updated: Jan 28, 2026

P50 Sensory Gating in Infants
Published on: December 26, 2013
Do Infants in the First Year of Life Expect Equal Resource Allocations?
Melody Buyukozer Dawkins1, Stephanie Sloane2, Renée Baillargeon1
1Department of Psychology, University of Illinois at Urbana-Champaign, IL, United States.
Insights
Young infants expect fair resource distribution, showing sensitivity to fairness very early in life. This expectation is observable under simple conditions, emerging in the first year of human development.
Area of Science:
- Developmental Psychology
- Cognitive Science
- Moral Psychology
Background:
- Previous research indicates fairness sensitivity in toddlers, but findings in younger infants are inconsistent.
- It remains unclear if infants younger than one year expect equitable resource allocation.
Purpose of the Study:
- To investigate whether young infants expect fair division of resources.
- To determine the conditions under which infant fairness expectations are observable.
Main Methods:
- Three violation-of-expectation experiments were conducted with 9-month-old infants (N=120).
- A fourth experiment tested 4-month-old infants (N=40).
- Infants observed animated puppets receiving cookie distributions (1:1, 2:0, 2:2, 3:1).
Main Results:
- 9-month-olds expected and detected unfairness (2:0) in a 1:1 distribution of two cookies.
- This expectation held whether cookies were given sequentially or via placemats.
- Infants did not show a preference for fair over unfair (2:2 vs. 3:1) distribution of four cookies.
- 4-month-olds also expected fair distribution of two cookies.
Conclusions:
- Infants demonstrate sensitivity to fairness from a very early age (as young as 4 months).
- This suggests an innate expectation of fairness is part of human moral cognition.
- Fairness expectations are observable only under specific, simple conditions in early infancy.
Abstract:
Recent research has provided converging evidence, using multiple tasks, of sensitivity to fairness in the second year of life. In contrast, findings in the first year have been mixed, leaving it unclear whether young infants possess an expectation of fairness. The present research examined the possibility that young infants might expect windfall resources to be divided equally between similar recipients, but might demonstrate this expectation only under very simple conditions. In three violation-of-expectation experiments, 9-month-olds (N = 120) expected an experimenter to divide two cookies equally between two animated puppets (1:1), and they detected a violation when she divided them unfairly instead (2:0). The same positive result was obtained whether the experimenter gave the cookies one by one to the puppets (Experiments 1-2) or first separated them onto placemats and then gave each puppet a placemat (Experiment 3). However, a negative result was obtained when four (as opposed to two) cookies were allocated: Infants looked about equally whether they saw a fair (2:2) or an unfair (3:1) distribution (Experiment 3). A final experiment revealed that 4-month-olds (N = 40) also expected an experimenter to distribute two cookies equally between two animated puppets (Experiment 4). Together, these and various control results support two broad conclusions. First, sensitivity to fairness emerges very early in life, consistent with claims that an abstract expectation of fairness is part of the basic structure of human moral cognition. Second, this expectation can at first be observed only under simple conditions, and speculations are offered as to why this might be the case.
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