The Algonauts Project 2021 Challenge: How the Human Brain Makes Sense of a World in Motion. - Radoslaw Martin Cichy; Kshitij Dwivedi; Benjamin Lahner; Alex Lascelles; P. Iamshchinina; Monika Graumann; Alex Andonian; N. A. R. Murty; K. Kay; Gemma Roig; Aude Oliva (CoRR, 2021)