The interaction of ability and motivation: Average working memory is required for Need for Cognition to positively benefit intelligence and the effect increases with ability

This study examined the role of working memory in the relationship between Need for Cognition (NFC) and intelligence. We previously reported that NFC is associated with intelligence but not working memory. This was unexpected as working memory has a strong relationship with fluid intelligence. 167 participants completed the NFC short scale, WAIS-III, and experimental working memory and fluid intelligence tasks. Moderation analyses revealed significant interaction effects between NFC, intelligence, and working memory. Working memory appeared to serve as a moderator between NFC and intelligence such that the positive effect of NFC on intelligence was only present for individuals with at least average working memory ability. There was evidence that the positive association between NFC and intelligence was increased with higher working memory.