The thing about emotional pain is that there is a source to it. External stimulus is perceived and translated into something we can understand. Then, it is bounced around our memories in an attempt to find context before it is converted into the conscious thought that we can articulate. Emotional pain only arises when our attempt to contextualize stimuli recalls a previous painful experience. Thus, our attempt to understand our own emotional pain is dependent on our abilities to recognize the role of memory in conjuring context.
The thing about drugs is that it creates an experience that cannot be replicated without drugs. Our perception of the experience that certain drugs invoke is dependent on our ability to contextualize our memories and adjusting the necessary distortions to replicate its effects. If you take acid, for example, your ability to understand the effects of acid on the mind is dependent on your ability to recall your experience when you are on acid. Yet, if something happens when you were on acid and you cannot remember your thoughts when you were on acid, then you effectively have never taken acid.
I find this to be an interesting concept because if you have a drug that makes you forget about the experience of being on the drug, then this experience effectively does not exist as a function of identity. If our access to our own memories constitutes the construction of our identity, then an inability to access memories would constitute a destruction of identity. If we were to take a metaethical perspective, if we are unable to contextualize where we are in the world, then we would not be able to identify ourselves.
In A Theory of Justice, Rawls postulates the concept of the veil of ignorance as a state of forgetfulness as a determinant of ethical value. If we have no memories of who we are, then we are effectively absent of identity.
For a long time, the concept of torture literally freaked me out. Elaine Scarry writes in The Body in Pain that the reason the experience of torture is so hard to understand is that the pain does not have a source. Once immense physical pain exists, it deconstructs the world in which we inhabit and reduces experience to the totality of the pain.
Thankfully, most of the pain I experience in my life is emotional pain, which I would honestly say is nothing compared to the worst physical pain I have felt. I don’t believe that there are forms of intense emotional pain that are equivalent to intense physical pain. Sometimes, when I find myself vomiting over a toilet from drinking too much, I question whether my subsequent forgetfulness is from the effects of alcohol on memory or the effect of intense pain on memory. Either way, I forget about how bad of an experience it was.
If I am exposed to something that causes emotional pain, then I would need to trace the path of how my perceptions have bounced around my internal world to translate into the negative sentiment that I feel. If I am able to identify which memories have been touched, then I am able to contain the effects of traumatic reoccurrence. Yet, per the nature of something as intangible as the internal world, the hard part lies in identifying the pathway between perception and sentiment.