[MarioWorldGamer (OP)]

I apologize for making these sorts of topics, but this is an important question.  I have a friend who suffers from horrible flashbacks and I have a question regarding flashbacks.  We know the types of experiences flashbacks can bring back such as certain smells, sounds, and emotions.

But are there certain types of experiences that cannot be brought back during a flashback such as feeling hungry, tired, thirsty, etc.?  The most important question I have here is, would that also include the completely altered and strange horrible mental states we experience in our dreams and nightmares?

These types of altered mental states during dreams and nightmares cannot be described.  They are entirely new experiences unlike any other.  They are not experiences like touch, smell, feelings, etc.  They are completely altered mental states.  So can those altered mental states be brought back and experienced during your waking life during a flashback or not?   

 

[evan_au]

These types of altered mental states during dreams and nightmares cannot be described.  They are entirely new experiences unlike any other.

Dream researchers wake dreamers as they are approaching the end of a REM cycle. They find that if the dreamer reports their dream immediately, they can describe and capture the general content of the dream (including the emotional content).
 
I have heard that dreams generally a greater concentration of negative emotions and the more aversive situations than the dreamer's real life.
See: https://en.wikipedia.org/wiki/Oneirology

I have a friend who suffers from horrible flashbacks

Dreams are usually forgotten soon after waking (in fact, the vast majority of dreams are forgotten even before you wake).

Flashbacks are a problem if they cause distress, are frequent, intrude on waking activities and the continuous panic state prevents relaxation. These are more likely to be flashbacks of very negative events, and fall under the banner of Post-Traumatic Stress Disorder.
See: https://en.wikipedia.org/wiki/Posttraumatic_stress_disorder

are there certain types of experiences that cannot be brought back during a flashback such as feeling hungry, tired, thirsty, etc.? 

I expect that almost any physical, emotional or mental state can be reconstructed in some form during dreams.
The operation of dreams is still somewhat mysterious, but they are known to be involved in memory consolidation. So it makes sense that they should be able to consolidate all kinds of real-world experiences.

I have experienced some exceptions:-
- In my experience, the sentences in a book have not been generated consistently in a dream state; so while there is a realistic experience of reading, I have used rereading the same sentence several times to identify a dream state, and enter lucid dreaming
- In lucid dreaming, you can generate experiences that do not correlate with the real world. I have heard of others using lucid dreaming to play out alternative scenarios and strategies that they have later tried in real life. 
- While making the sudden transition from nightmare to waking, you try to carry out your dreaming action (eg running away) on your real body. But your body is still paralysed in a dream state, so you have the experience of trying to run, but not being able to move your legs.

[mrsmith2211]

Can you clarify when the flashbacks are happening, waking up from a dream, or during awake activities. Awakening at night after a dream is a whole different scenario than experiencing flashbacks during normal day to day activities.