It will be difficult if not impossible to overcome the disadvantages of deficiencies in early childhood stimulation later in adulthood. But now trends in both brain science and cognitive science have converged to bring about revisions to these ideas from the conventional wisdom. For over a decade, the James S. McDonnell Foundation in St. Louis has supported extensive research in neuroscience. Enriched early childhood environments causes synapses to multiply rapidly. Early experience does not cause synapses to form rapidly.
More synapses mean more brainpower.
The plateau period of high synaptic density and high brain metabolism is the optimal period for learning. The neuroscientists who count synapses in humans and monkeys merely point out that during the plateau period, monkeys and humans develop a variety of skills and behaviors.