The image below marks a shift in Matisse’s work. prior to this he focused on colorful patterning throughout his pieces. The Portrait of Yvonne Landsberg was created in 1914, at the height of WWI. Having returned from Morocco the year before, Matisse was met with the dark realities of the eminent war. He worked with darker hues primarily using blacks and greys.
during this period Matisse was also interested in letting the public into the painters process. He was no longer concerned with hiding the grid lines and markers artists use to set up their compositions. The sketch like brush strokes surrounding the figure of Yvonne play with this idea of process, mimicking the possible sketch marks created in the construction of the piece.
Dreaming Eyes of Wonder 
The direction that his work went as you point out is a recent new revelation to me; last weekend I visited the Tate Modern on my way back from Barcelona and was amazed (through the curator’s explanations) to discover that Matisse was genuinely avant-garde to his contemporaries. This departed from my instinctual expectations of his work (because of the cliches), that Matisse created accessible, almost “pop” art owing to those iconic images of dancing nudes, and colorful Gaugin-like portraits.
Looking forward now to seeing the MoMA show, thanks for the heads-up.
I had the same reaction. A friend of mine over the weekend had asked me what I thought of Matisse, because my house is filled with Van Gogh. I shrugged my shoulders and said I didn’t hate his work. So I decided to dedicate that sundays post to Matisse. As I was searching images I can across this work, which was very unlike many of the pieces I had seen before. I really liked it. I recently visited the Munch exhibit at the NGA and it reminded me a little bit of those woodcuttings (probably because of the dark tones and themes in the piece). So I decided to do a bit of research on the piece, and then stumbled upon the MoMA show. I’m looking forward to heading up to NYC to visit the show soon.