This is quite profound compared to the average person who is not even a visual thinker. Those who think in pictures take it for granted this is how everyone does it, but they are in the minority. Most people cannot picture something in their mind’s eye, they have to remember what something looked like and construct a memory bank of facts in order to describe something they have seen previously. So what is in their head when they close their eyes is blackness and thoughts alone, but not imagery. So what you were describing for Tesla is an exquisite capability to visualize and use it creatively, to vary things and witness the changes with great accuracy and precision, such that he could even predict when things would work, where there was space physically for a mechanical action to happen, and so on. So his was an extreme degree of innate capability to manipulate visual representations of physical objects, so he did not need a drawing board and measurement devices, and so on, but could simply see it in his mind and alter it incrementally in any way he chose.
This has analogies with other senses with which some individuals have extraordinary gifts. This is true in the case of some musicians who will compose entire symphonies in their head without reference to a musical instrument to hear what chords sound like, and melodies might sound like when played note by note. They can construct the aural panorama of a multiplicity of instruments going at once—speed it up, slow it down, vary the texture and the dynamics in ways to hear it differently, and then transfer that through music notation onto a written manuscript that can be followed by musicians, and conducted for a concert by an orchestra to reproduce what originally was thought alone, at one point, generated creatively through the consciousness of the composer.
Here, too, are signposts that there is a well of creativity existing somewhere that innovators tap into. They are not all simply conjuring things up from nothing on the fly, they are deriving inspiration from an infinite set of possibilities, and essentially uploading that into their awareness, and often with divine help as a collaboration, and that is true of profound work of all kinds. This is why artists, writers, and musicians will talk about having a muse, a mysterious inner voice, a well of inspiration that will start to flow at times and may bring forth a work wholesale, from first to last, or it might be in segments, pieced together over time, but only when the muse is present and bringing something forth to be experienced and observed and captured for use in the future. Here, too, are elements of conscious interaction, only possible from consciousness being “non-local,” meaning, “extending beyond the brain itself.”