Abstract: A monitoring device (24) includes a band (32), configured to fit around an appendage of a human subject (22), and one or more sensors (46, 58, 60, 62) fixed to the band and configured to sense physiological parameters of the human subject. In one embodiment, at least one visible light source (82) is fixed to the band. A controller (64) is fixed to the band and is coupled to receive signals from the sensors and to actuate the at least one visible light source in response to a state of the device. At least one flexible light guide (40) is embedded in an outer surface of the band while extending around at least a part of a circumference of the band when fit around the appendage, and is coupled to receive light from the visible light source and to emit the light from the outer surface in a bright stripe along a length of the light guide.