Perhaps one of the most powerful emotional state that inhibits the work of scholars is hopelessness. Hopelessness can come in various intensities and can attack scholars for a variety of reasons. Sometimes, even the smallest defeat will trigger a powerful wave of hopelessness.
Consider the following "sources"
A senior colleague says something critical about your the type of work you do
An article comes back from a journal rejected
A grant you applied for was rejected
A colleague who you started the same time as is going up for tenure early
These are but a few. But are they really the source, or are they merely triggers? This is the type of self exploration that you must do. Without bringing these issues to light, you my be thrown off when hopelessness attacks.
Think about this post, and perhaps write a bit in your academic journal (or start one if you did not have one yet).