Incoherent.  Is this not the word you use when you cannot understand someone for they are making no sense?  There are various things that can cause one to become incoherent:  mental confusion, ingested substances, fear, lack of focus Coherence is necessary to communicate not only in this earthly realm, but most especially with the so-called higher realms.  How do you become coherent?  Cleanse the energetic body regularly of dissonant energy, find balance in your life, become centered, heal emotional wounds, practice presence all of these lead to a greater ability to get in touch with other aspects of the Self.  Become coherent at will and you will connect.