Image and words.
Thoughts go in math also...#s... if you really sit down and think.
Concentration is difficult for me all the time because I usually hear things during PRing, first distracting thoughts, then relevant phrases to the book.
Trying writing on images and not using subvocalization to guide your fingers...
Chang
ps - also try DVORAK keys eyes closed! :P
softgaze and eat up the layout in pdf. Then ask your inner mind to guide you to type phrases. That's my "dictionary game".