Gain a basic understanding of biomedical optics and of propagation of the light in the human tissue; Provide a literature review on commercial, FDA approved and clinical/gold standard research tools detailed within academic papers for comparison of optical devices; Determine methodologies used for assessment/comparison of PPG signals within literature; Acquire PPG signals with Holst Centre’s wearable optical patch and compare devices within specific methodologies; Communicate via presentations and report writing findings.