Gosh, I would naturally assume they are, esp. when affecting communication - intake of information or expression of it, but that is just my guess on the matter.

Here is a link to a handbook from the state of Co., but it looks like this definition would be state-specific, at best. It does appear to include physical limitations/disabilities.

http://www.cde.state.co.us/gt/download/pdf/TwiceExceptionalResourceHandbook.pdf

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