I admit to some doubts on the methodology, which stem from the concept behind this research. In reverse order, I am concerned that the visual analog scale could be correct. Is it possible to have a reluctance to learn something? Possibly, but rarely. A negative response to the question regarding interest in learning how to rate restaurants is correctly answered as "none, indifferent." I seriously doubt that a person could have a negative attitude to this as strongly as he might have a positive attitude. For a person who doesn't want to know, the correct response would be "indifferent." 

The first question is more general: is it possible to study curiosity in humans without first relating it to curiosity in other animals? Practically all animals display exploratory behavior when placed in a novel environment. Most show some signs of apprehension/anxiety, and the exploration serves the purpose of alleviating that anxiety. So perhaps human curiosity began as a survival factor: the curious survived because they explored the back of the cave, and the indifferent were eaten? I think it is possible to make a case that curiosity began its ontological life as a measure of reducing fear of the unknown and was subsequently modified when language developed. 

I would be interested to explore this further. 

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I would like to comment on Dr. Niall McLarren's first question:

"The first question is more general: is it possible to study curiosity in humans without first relating it to curiosity in other animals?"

Of course it is related, we discussed in our paper that the knowledge instinct orginated possibly from back to Amniotes.

The principal point in our paper is that the knowledge instinct is a different mechanism from "survival." And there are specific emotions "aesthetic emotions" related to satisfaction of the knowledge instinct. These emotions are fundamentally different from basic emotions related to other insticts and drives. Aestetic emotions are foundations of all human "higher" cognitive abilities

Leonid Perlovsky

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  published extensively in related areas

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