What is the term for the "knowing what you think but can't explain it" phenomenon?
Mental block

A mental block is an uncontrollable suppression, or repression of painful or unwanted thoughts/memories. Also can be an inability to continue or complete a train of thought, as in the case of writer's block. In the case of writer's block, many find it helpful to take a break and revisit their topic.

You can also check out a list of synonyms and related words for &quot;forgetful and forgetfulness&quot;.