Aphantasiac here so this raises an obvious question. Cursory search suggests visual hallucinations due to drugs or schizophrenia are reported. Conscious and involuntary visualisation seem to be somewhat independent.
Using this data, one would expect to see only 0.25 cases in those 66 blind kids.
Stated differently, there is around a 78% chance of having 0 cases in those 66 by random chance alone.
Dumb.