Does the use of cannabis affect the ability to recall dreams? Will cannabis be a negative factor in the ability to recall dreams from waking up.

How do the cannabinoids affect you when in a dreaming state?
Current research tells us that yes, cannabis will affect the ability to recall dreams. As for the negative - positive outcomes, it seems to be subjective.

One of the few researchers in this field, Hans Hamburger says:


  “By smoking weed, you suppress the REM sleep, and with that you also
  suppress a lot of important functions of that REM sleep. One of those
  functions is reliving the things you have experienced and coming to
  terms with them, as it were. Processing all kinds of psychological
  influences is something you do in REM sleep.
  
  You also anticipate the things that will happen the next day or the
  days after that. While you’re sleeping, you already consider those and
  make decisions in advance.” – Hamburger


You can find more of his publications here: https://www.ncbi.nlm.nih.gov/pubmed/?term=Hans%20Hamburger