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I found this article through an interest in the “what do the blind “see” when they dream” question, as it was formulated by Eliezer Sternberg. I was originally skeptical about the idea that the blind have a completely non-visual interpretation of an isotropic model of space. I decided the synesthetic hallucinations induced by classical tryptamine hallucinogens might could provide interesting evidence as to how the blind experience internal models of space. I queried “congenitally blind” and “tryptamines" and found a number of reposted iterations of the following article.  
They all referenced, in one way or another, the case study linked below that can be accessed via the proper credentials or by paying a fee.

In short a congenitally blind Russian rock musician, who chose to self identify as Mr. Blue Pentagon for the purposes of the study, described a number of his experiences after having imbibed (what is presumed to have been) lysergic acid diethylamide 25 (more commonly known as LSD). He described experiences of synesthesia induced by recorded music. Specifically, he described the experience of listening to a Bach piece as having qualities typical of multimodal perception, such as “height” or depth or as if he was being “showered” by or immersed in sounds.

One could hypothesize, based on the above, that the “cross chatter” seen on fMRI between brain regions in individuals who have consumed tryptamines has a similar effect on the spatial perception that the visual cortex has accommodated to process in the congenitally blind.

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