Twenty high mental age (MA) subjects and 33 low MA subjects who had been in a free word association test 30 months previously were retested with the Moran 80-Word List. At the time of the previous testing, subjects in the high group had a mean chronological age (CA) of 17.1 and mean MA of 11.5; subjects in the low group had a mean CA of 15.3 and mean MA of 7.6. Associated words were scored for variability of predication, functional relationship, synonym, superordinate, logical coordinate, contrast, faults, and commonality. The low group showed a significant increase in the number of dimension-referent responses (p .01), reduced their reaction time (p .001), and increased their commonality scores (p .01). When all faults were combined, excluding the assonance responses of two subjects, the reduction in faults was significant (p=.001). The results supported the prediction of no significant change in word association structures in the high group and a shift in the direction of the high group by the low group, due to continued maturation during the 30-month interval. (SN)