How much RAM and hard drive space does a human brain have?

The closest comparison to RAM in our brains is short-term memory.
While computers encode information in a binary code of either on or off, the synapses in our brains are more complicated. (Pixabay)
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How much RAM and hard drive space does a human brain have? asks nine-year-old Richard Robinson-Orozco.

Lisa Saksida, a professor at Western University in London, Ont., says the closest comparison to RAM in our brains is short-term memory. 

Human short-term memory holds about seven items. "Our RAM is probably quite improvished compared to a computer's," says Saksida, who holds a Canada Research Chair in translational cognitive neuroscience.

Less is known about the hard drives in our brain than the ones in computers.

Saksida says a rough guess is the human brain contains 90 to 100 billion nerve cells or neurons. Each neuron makes about 1,000 connections to other neurons. Multiplying it out gives 100 terabytes of information, assuming each connection or synapse holds 1 byte of information. 

But while computers encode information in a binary code, either on or off, synapses are more complicated. Given how cells interact each other, each one helps with more than piece of information at a time, Saksida says.