The physiological origin of task-evoked systemic artefacts in functional near infrared spectroscopy. - Evgeniya Kirilina; Alexander Jelzow; Angela Heine; Michael Niessing; Heidrun Wabnitz; Rüdiger Brühl; Bernd Ittermann; Arthur M. Jacobs; Ilias Tachtsidis (NeuroImage, 2012)