Among all the Impressionists, van Gogh was the one who was influenced the most by Japanese prints and ukiyo-e aesthetics.  He even made a number of oil copies of woodblock prints.  He did not merely copy the prints.  He was concentrating on the forms that were essential to the composition.  Japanese art gave van Gogh the confidence to remove conventional kinds of modeling.  It taught him about the expressive power of large areas of a single color brushed in relatively flatly.  He also learned the enormous decorative power of unbroken contours, lines which he drew not uniformly in black but also in a variety of other colors.

In each of his portraits, van Gogh had the same extraordinary intensity of expression concentrated in the eyes.  In Self Portrait (1886) he used Neo-Impressionist brushwork, whereas in Self Portrait Dedicated to Paul Gauguin (1888) he painted himself like a Japanese man. 

He wrote to his brother, "I have conceived it as the portrait of a bonze, a simple worshipper of the eternal Buddha.The head is modeled in light colors painted in a thick impasto against the light background with hardly any shadow.  Only I have made the eyes slightly slanting like the Japanese." (Quoted by Fred Orton, Japanese Prints Collected by Vincent van Gogh, Amsterdam: Rijksmuseum, 1978, p.14)