Hyperphantasia is the condition of having extremely vivid mental imagery. It is the opposite condition to aphantasia, where mental visual imagery is not present. The experience of hyperphantasia is more common than aphantasia and has been described as being "as vivid as real seeing". Research indicates that 2–3% of people have aphantasia, and up to 10% have hyperphantasia. These numbers refer only to the extremes of visual imagination; currently there isn't much data on other mental senses.
If we go back to the original Galton study, people reporting extreme imagination listed experiencing mental imagery that was:
•Brilliant, distinct, never blotchy
•Comparable to the real object, as if they were actually seeing it
•Feel dazzled, like you would when looking into the sun
•Clearness, brightness
•High definition
•"As if the reality is before me"
