Not sure I'd call it one of Brakhage's more accessible films, but it's definitely one of his least abstract ones. If you like Brakhage's style of filming and editing, but aren't taken with the abstract images that exemplify his work, you may want to give this film a chance. Be sure to read up about it up front though.
The Act of Seeing with One's Own Eyes is an unflinching autopsy documentary. There's a ton of dead bodies, often very mangled ones, that get examined. A lot of it involves cutting up the remains and cleaning up the mess afterwards. These are not pretty pictures and will probably be considered very shocking by many.
But, as the title of the film explains, that's pretty much the point. It's just a shame that Brakhage refuses to add a soundtrack to his work and that film simply can't substitute the real deal, which takes away some shock effect of this documentary. This comes from a longtime horror fan though, so make sure you know what you're getting yourself into.