In a finding sure to inflame the math wars, a team of neuroscientists has revealed the crucial role played by rote memorization in the growing brains of young math students.

Memorizing the answers to simple math problems, such as basic addition or the multiplication tables, marks a key shift in a child’s cognitive development, because it helps bridge the gap from counting on fingers to complex calculation, according to the new brain scanning research.

The progression from counting on fingers to simply remembering that, for example, six plus three equals nine, parallels physical changes in a child’s brain, in which the hippocampus, a key brain structure for memory, gradually takes over from the pre-frontal parietal cortex, an area of higher order reasoning.

Related: Math Forum.