Some evidence for the existence of a general factor of semantic memory and its components

This paper is concerned with the issues of the factorial structure of long-term semantic memory, with what are the major domains of long-term memories for different kinds of information and knowledge, and whether these are positively intercorrelated to form a general factor of long-term semantic memory. The methodology of the study consisted of the construction of a test of general knowledge, which endeavoured to cover all major areas or domains of general knowledge in western cultures. This was administered to 509 females and 209 males, mean age 20.9 years, most of whom (638) were undergraduate students. Nineteen measures conforming to primary domains of general knowledge were subjected to confirmatory factor analyses, using LISREL 8.30. A model with six first-order factors (Physical Health and Recreation, Current Affairs, Fashion, Family, Arts and Science) showed a good fit to the data (SRMR=0.047). In a subsequent higher-order factor analysis, the six first-order factors loaded substantially (range 0.54–0.90) on a single second-order factor (SRMR=0.050). Thus, all domains of general knowledge tested in the study were positively intercorrelated and explicable in terms of a strong general factor of long-term semantic memory ability. The six first-order factors are probably expressions of interests.