Insufficient Nutrition and Stimulation

Malnutrition interferes with brain cell production, reduces brain weight, and is particularly damaging during the first 6 months of life when the brain's nerve cells grow larger and the majority of synapses are formed. The result is lower than expected IQ and learning ability, poorer social adaptation, and reduced initiative. Fortunately, studies find that some reversal of the negative effects of poor nutrition is possible after several years of adequate nutrition and enriched care giving.

Early sensory deprivation also adversely affects brain maturation and learning. Even milder losses in stimulation, such as late entry into school, intermittent attendance at school, and dropping out can negatively affect intelligence.

Numerous animal studies since the 1960s have demonstrated how reduced learning opportunities affect brain development. Conversely, enriched environments and learning opportunities result in thicker gray matter, more glial cells, higher brain metabolic activity, and more chemicals needed for neural transmission. Likewise in humans, learning experiences "pump the brain" (Bakker, 1984, p. 1) such that "the brain after learning is a different one than the brain before learning" (Merzenich & Jenkins, 1995, p. 249). Parents and teachers can do much to "help the brain remake itself' because "the life we lead leaves its mark in the complex circuitry of the brain-footprints of the experiences we have had, the thoughts we have thought, the actions we have taken" (Begley, 2002, p. B4).