"The Mathematical Brain"

- What do we mean by "the mathematical brain?"
The mathematical brain refers to an inborn ability that humans have that allows them to map numbers into their brains. In other words, our brains are set up from birth to understand numbers and number patterns.

- What do we do when we are asked to compare two numbers?
When we are asked to compare two numbers, we change those numbers into pieces of lines. Then we compare the length of each piece, so that we can decide which number is larger.

- How did scientists learn about the mathematical brain?
Scientists learned about the mathematical brain by studying patients who had suffered brain injuries.

- What is acalculia?
Acalculia is a loss of the ability to calculate and solve mathematical problems.

- Dehaene’s most famous patient was known as "the approximate man." How do you think he got this name?
This man was able to decide which of two numbers was bigger or smaller even though he could not perform mathematical calculations. He did this by comparing the numbers.

- What had earlier researchers noted in their studies of patients with acalculia?
Earlier researchers had noted that patients with acalculia usually had other problems too. For example, some confused directions; some could not name the fingers of their hands; and some could not write. All these patients had injuries to the same part of the brain--the inferior parietal cortex of the left hemisphere.

- Which part of the brain seems to be involved in simple number processing?
The inferior parietal cortex in the left hemisphere of the brain seems to be involved in simple number processing.

- Do scientists know how the brain actually processes numbers?
No. The scientists only know which part of the brain processes numbers, but they do not know how that part of the brain does it.

- What happens in the brain as we learn to perform more precise mathematical calculations?
When we go to school and learn more complex math, the mental number line in our brain gets more developed. At this point, other parts of the brain such as the basal ganglia in the left hemisphere become involved along with the inferior parietal cortex.

- What do PET scans of normal brains show during mathematical processing and calculation?
PET scans of normal brains have shown that there is usually activity in the inferior parietal cortex when people are processing numbers and that when someone is doing multiplication, there is a lot of activity in the left basal ganglia.