All sorts of involved material has been written about the development of cognitive precursors in prenatal people,⇲ including the functions that contribute to symbolization (and therefore language), and I’m not going to be able to do it justice in this summary;⇲ however, if you want to understand what has not been going well for someone, then you need to know at least something about what should have been happening.
So here goes.
You don’t have to read it now, but I will connect the section of my communication tutorial that details the full array of sensory systems that are available to us. This link (a) creates an easily available reference and (b) grounds the following uses of the terms “exteroceptive” and “interoceptive.”⇲
Prenatal exteroceptive senses develop in the following order: touch, taste, smell, hearing, and sight. Red is distinguished. Objects receive enough focus to track them, which means that there must be some amount of engagement in figure/ground distinction.
There isn’t a whole lot of reliable information on the prenatal development of interoceptive senses,⇲ other than various suggestions that it seems like it should happen,⇲ and relatively speculative inclusions in descriptions of more general sensorimotor observations.⇲ Pain is sensed. Those senses that rely on gravity would be affected to some extent by the fact that the prenatal person is floating, so generalization to life in/on the outside would not be straightforward.
Crucially, though, we know that prenatals can extract at least some of the signal from out of the noise in their world, turning at least some of their time-stream into relevant information segments.
Learning to determine such boundaries is a massively big deal.
And then subsequently determining them is as well.
I am going to try to narrow things down a bit.
“We found evidence that the auditory system has internalized these statistics and uses them to group features into coherent objects.”