In the present study, speeded tasks with differing assumed difficulties of the trials are regarded as a special class of simple cognitive tasks. Exploratory latent growth modeling with data-driven shape of a growth curve and nonlinear structured latent curve modeling with predetermined monotonically increasing functions were used to analyze…

Inspection time (IT) and Peabody Picture Vocabulary Test (PPVT) scores from 75 school children aged 6-13 years in 2001 were compared with the performances of 70 children aged 6-13 years who had attended the same primary school in 1981 ["J. Exp. Child Psychol." 40 (1985) 1.]. ITs for the 2001 sample were measured with the same four-field…