Is it impossible for a human to feel pain in a dream?

Question

I am absolutely sure that humans can feel emotions in a dream. I've experienced some of the strongest anxiety in my life during nightmares. Sometimes the emotions were strong enough to persist in the real world - I remember once seeing my father at the lunch table and feeling my metaphorical hackles rise, preparing to hurl an argument at him - and being confused why I can't come up with a good argument, until I remembered that I'd just dreamed the heated argument we'd had, and my feeling mad at him wasn't due to any cause existing in waking reality.

I have also experienced sensory inputs which were definitely present in the real world and got seamlessly incorporated in the dream, e.g. the sensation of a full bladder, or of being cold. So I'd think that in general, sensory inputs from the body can be felt when one's sleeping and dreaming. Also, I think that it is possible to dream some sensory state which doesn't have a cause in physical reality, just like it happens with emotions (but can't remember an exact dream where this happened).

On the other hand, one of the most overused tropes in fiction is heroes who pinch themselves to make sure they aren't dreaming. I find this quite strange. If my understanding of sensory input in dreams is correct, a pinch shouldn't be any proof - a person could feel the pain while dreaming, and keep on dreaming. Maybe the logic behind that is that pain is such an important signal, that when it is felt, even if it was caused by a dream, the brain will awaken the body to prepare it for response to a danger - so pinching oneself in a dream will lead to dreamed pain, which will lead to an awakening.

I have never felt compelled to pinch myself to test if I am dreaming - certainly not in waking reality, and if I did it in a dream, I must have forgotten that dream, which means that it can't have worked. I have sometimes surfaced of a dream enough to notice that I am dreaming, decide either "what a lovely dream, I want more" or "dumb dream, I want something more pleasant" and continue dreaming without waking up, and sometimes I can really take decisions at that point which influence the story of the dream. So it is plausible that a person could decide at such a point that they will now pinch themselves, and dream that they are doing it. But will the resulting pain be enough to wake them up? Or will they experience no pain at all from a "dream pinch"?

And is there any way at all to make a dreaming person experience pain - either from external stimuli, or from a voluntarily dreamt pain stimulus like the pinch, or from an involuntary dreamt stimulus like the dreamer dreaming that a car is hitting them? What happens when a dreaming person experiences either of these three?

Answer 1

Experimental evidence suggests that it is possible to experience pain while dreaming, though it does appear to be quite uncommon.

I refer to two papers, both published by the American Academy of Sleep Medicine, in the journal Sleep:

The first, produced in 1993 by researchers at the Laboratoire du Sommeil, Hôpital du Sacré-Coeur de Montréal, Québec, Canada:

Experiences of dreamed pain were reported incidentally in 2 experiments on the effects of somatosensory stimulation administered during REM sleep. Dreams were selected from 5 Ss who had reported at least 1 instance of dreamed pain in the studies. Ss had undergone 42 stimulation trials over 20 nights and had reported a total of 13 dreams (31%) with 1 or more references to pain. There was a high level of individual variability in susceptibility to dreaming about pain. Most often, the references to pain appeared to be direct, untransformed incorporations of real sensations produced by stimulation. Pain was in many cases associated with strong emotion, typically anger. Thus, pain is compatible with the representational code of dreaming. Further, the association of pain with dream content may implicate brainstem and limbic centers in the regulation of painful stimuli during REM sleep.

An additional paper, produced by researchers at the Burn Center Hĵtel-Dieu du Centre hospitalier de l'Université de Montreal, Quebec, Canada:

It has been shown that realistic, localized painful sensations can be experienced in dreams either through direct incorporation or from past memories of pain. Nevertheless, the frequency of pain dreams in healthy subjects is low. This prospective study was designed to evaluate the occurrence and frequency of pain in the dreams of patients suffering from burn pain. Twenty-eight nonventilated burn victims were interviewed for 5 consecutive mornings during the first week of hospitalization. A structured-interview protocol was used to collect information on dream content, quality of sleep, and pain intensity and location. Patients were also administered the Impact of Event Scale to assess posttraumatic symptoms. Thirty-nine percent of patients reported 19 pain dreams on a total of 63 dreams (30%). Patients with pain dreams showed evidence of worse sleep, more nightmares, higher intake of anxiolytic medication, and higher scores on the Impact of Event Scale than did patients reporting dreams with no pain content. Moreover, patients with pain dreams also had a tendency to report more intense pain during therapeutic procedures. Although more than half of our sample did not report pain dreams, these results suggest that pain dreams do occur at a greater frequency in suffering populations than in normal volunteers. More importantly, dreaming about pain may be an added stress for burn patients and may contribute to both poor sleep and higher pain intensity, which could evolve into a cycle of pain-anxiety-sleeplessness.