There are a few studies on the chameleon brain and nervous system, but for the most part they are detailed anatomy articles found in old journals that require a considerable understanding of the brain already. Was there anything in particular you were curious about? A couple trends you see is that the cerebellum is highly developed (important in balance and equilibrium), the olfactory bulbs are tiny with slender peduncles (suggesting limited ability to smell), the nucleus sphaericus is reduced (suggesting limited vomeronasal capacity), the basal optic root ganglion is well developed (good eye movement control), and the hypoglossal nucleus is highly differentiated (complex and highly evolved tongue projection mechanism).
Chris