The brain probably stores around 10-100TB of data.
According to Forrest Wickman, computational neuroscientists generally believe the brain stores 10-100 terabytes of data.1 He suggests that these estimates are produced by assuming that information is largely stored in synapses, and that each synapse stores around 1 byte. The number of bytes is then simply the number of synapses.
These assumptions are simplistic (as he points out). In particular:
- synapses may store more or less than one byte of information on average
- some information may be stored outside of synapses
- not all synapses appear to store information
- synapses do not appear to be entirely independent
We estimate that there are 1.8-3.2 x 10¹⁴ synapses in the human brain, so according to the procedure Wickman outlines, this suggests that the brain stores around 180-320TB of data. It is unclear from his article whether the variation in the views of computational neuroscientists is due to different opinions on the assumptions stated above, or on the number of synapses in the brain. This makes it hard to adjust our estimate well, so our best guess for now is that the brain can store around 10-100TB of data, based on this being the common view among computational neuroscientists.