Research going back to the sixties shows that early cognitive stimulation has only a transitory effect. The gains pre-schoolers make from these programs don’t hold up in the early grades. Lack of brain maturation may be holding things back. Parents boast that their very young children can now read — thanks to electronic game formats, but the kids may be learning to word-call, not read. That’s because reading comprehension requires abstract thinking. In fact, the overstimulation of the visual approach may impede auditory (phonics) learning later on. Be careful, parents.