People with amazingly clear mental images.
Cossins writes about those people with the unusual condition of hyperphantasia. Such people routinely have remarkably clear and lifelike mental images by comparison with the rest of us. It turns out that there is probably a spectrum of mental imagery, although it is hard to measure this. At the other end of the spectrum, some people have very limited mental imagery. This is called aphantasia. Most of us are somewhere between the two extremes. Perhaps, before mankind developed language, most people had hyperphantasia. Perhaps language took us from a world of mental imagery into a world of mental words, our inner dialogue.
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