Abstract

Background: Iron deficiency is the most prevalent micronutrient deficiency worldwide. There is evidence that iron deficiency produces alterations in the developing brain, eventually leading to long-lasting effects on various cognitive functions. Methods: Here, we investigated motor learning and its consolidation after sleep in adolescents who sustained iron deficiency anemia (IDA) in infancy, compared to healthy controls, in the context of a long-term follow-up Chilean research project. Fifty-three adolescents who formerly had iron deficiency anemia as infants and 40 control adolescents practiced a sequential motor finger tapping task, before and after a night of sleep. Performance was measured at the end of learning, 30 min later (boost effect), and the next morning. Results: Revealed slower learning in subjects with infant iron deficiency anemia than control subjects, followed by a proportionally similar performance boost at 30 min. Performance remained stable overnight in healthy controls but further improved in infant IDA adolescents, suggesting a beneficial effect of post-training sleep on the consolidation of incompletely learned motor skills. In particular, overnight gains in performance were observed in female, but not male infant iron deficiency anemic subjects, suggesting a gender effect. Conclusions: Our results indicate long-lasting motor learning deficits in infant IDA adolescents and provide support to the hypothesis that post-training sleep might, to some extent, compensate for hampered motor learning during wakefulness. (C) 2019 Elsevier B.V. All rights reserved.