John Wen, Agung Julius, and LESA researchers at UNM were published in the prestigious Chronobiology International Journal for their work on ‘Actigraphy-based parameter tuning process for adaptive notch filter and circadian phase shift estimation’.
The composite of research used by both the LESA team at Rensselaer and the team at the University of New Mexico that led to this publication is the result of a long-standing collaboration of bringing engineered solutions to human factor studies to help better understand the relationship of dynamically tuned lighting and circadian phase shift. The researchers developed a novel adaptive notch filter (ANF) modeling process, that allows them to estimate the circadian phase shift from the actigraphy data rather than saliva samples. They were able to demonstrate how the ANF algorithm, when applied to the actigraphy data, is able to estimate the circadian phase as determined by the Dim light melatonin onset or DLMO – the “gold standard” method for identification of circadian phase. Their results demonstrate that applying ANF with a well-defined parameter tuning process to actigraphic data can provide accurate measurements of the circadian phase and its shift without resorting to salivary melatonin collections according to their published data.