Validation of a Novel Method for Use in Studies of Iron Status, Brain Function (EEG), and Recognition Memory Performance in Infancy

Abstract

BackgroundEarly infancy is a time of peak cortical development when young infants are more susceptible to cognitive deficits from nutritional deficiencies. Previous studies link EEG measures of brain function to behavioral measures during recognition memory tasks in early infancy, but few in the context of nutrition deficiencies. Animal studies have shown that specific nutritional deficiencies affect the brain in targeted areas rather than as a broad cognitive change, but many current studies of nutrition and cognition in human infants only use general measures of cognition.ObjectiveOur study is unique in looking at early infant recognition memory, brain function, and iron status. This analysis examines the relationship between behavioral and brain (EEG) measures of memory as a validation of methods that could be applied in subsequent studies of the relationship between infant iron status and cognitive function.MethodsEEG data were collected from infants (4–6 mo, N=30) during a memory task (Oddball) in which the infants observed novel and familiar stimuli of emotionally neutral female faces. During a related memory behavior task (Paired Comparison), infants viewed two faces simultaneously and the length of infant gaze at each stimulus by stimulus type was measured. Hemoglobin and serum ferritin were measured to assess anemia and iron stores, respectively. The main EEG outcomes were the difference in amplitude and slope of the late slow wave (ΔLSW) between novel and familiar stimuli, a known measure of memory. The percent of time spent looking at the novel versus familiar stimuli (%Nov), as well as the total time spent in attention were the main memory behavior outcomes. Student's t‐tests and regression modeling were used to analyze the association between ΔLSW and %Nov. Age, sex, race, birth weight, and maternal education were assessed as potential confounders in regression models.Results and ConclusionsPreliminary results show that ΔLSW was significantly associated with %Nov (β = 0.52 ± 0.27; p=.04). These results show that our novel combination of methods successfully measures recognition memory and improves on previous work by using specific behavioral tasks and measures of brain function in the context of infant iron deficiency. This study will inform future work in the fields of nutrition and cognition.Support or Funding InformationFunded by USDA/CUAES (Hatch #NYC399413) and Cornell Human Ecology Alumni Association; JEHN supported by NSF GRFP