Fig. 3

Changes over time in lexical diversity and talkativeness during conversation predicted by family-related variables. Plot a represents estimated average trajectories over time in lexical diversity during conversation for individuals with maternal perception of child’s reciprocated closeness at the mean (green), 1 standard deviation (SD) below the mean (red) and 1 SD above the mean (blue). Closer mother-child relationship was positively associated with the rate of change over time. Plot c represents estimated average trajectories over time in talkativeness during conversation for individuals with mothers who graduated college (red), and mothers who graduated high school (blue)