I've been working for ~8 years in a mix of environments, some with syntax highlighting and some without. When working without highlighting, I rely on the shape

I've been working for ~8 years in a mix of environments, some with syntax highlighting and some without. When working without highlighting, I rely on the shape of the code's text and the search function of my editor to navigate as I jump around code. With syntax highlighting, I have those tools, and extra navigational cues provided by little islands of color. I haven't noticed a difference in my scanning speed or code comprehension between the two. It may be there, but I'm not conscious of it. Consciously, I've got a slight preference for the colorization. It makes the code feel "friendlier", and I'm happier to be looking at it. The un-highlighted environments tend to be older Unix machines with other annoyances in the operating experience, so I'm sure that plays a lot into my perception.