C. Aubuchon, R. Vergne, S.A. Cholewiak, B. Kunsberg, D. Holtmann-Rice, S.W. Zucker, & R.W. Fleming, Orientation fields predict human perception of 3D shape from shading, Proc. Natl. Acad. Sci. U.S.A.

Adding notes and sketches in a reflection journal can be an enjoyable way to process information and record observations.