Listening to “Start the Week” on BBC Radio 4 this morning (15 March) I was astonished to hear one of the participants use this word and pronounce it /kɒgˈnaɪtɪv/. This is not given by any of the current dictionaries of pronunciation, nor by the OED, and I’ve been wondering what model he was taking in order to arrive at it.
There’s decisive, with its noun decision, as cognitive has cognition, but decisive has the verb decide, for which cognitive has no equivalent (cognize?).
Attrition does give attritive /əˈtraɪtɪv/ but OED notes this as a rare word. Excitive /ɪkˈsaɪtɪv/ – latest quotation 1862. Incitive /ɪnˈsaɪtɪv/ – 1888.
And out of 200 words ending -itive, these are the only ones with pronunciation /-aɪtɪv/.