Human Memory Prosthesis

Cave Paintings became writing, photography, and film, sundials became clocks, the abacus became the calculator, and all of these other tools supplementing human cognition gave way to the computer. We are as smart as our technological brain-extensions allow us to reach beyond our grasp.

Mathematician Von Neumann estimated the total memory storage for a human brain at 1 Exabyte or 10²⁰ bits in 1950. Anatomists lowered the estimate to 10¹³ to 10¹⁵ in the 1970’s. Thomas Landauer lowered the total memory a human stores in a lifetime to 100 Megabytes in 1986, based on our retaining 2 bits per second of “visual, verbal, tactile, musical memory” multiplied against an average human lifetime of 2.5 billion seconds.

Whether you believe the best estimate or that we have less capacity than a CD Rom, our memories are highly flawed. Look at ourselves in an old photo album, and we realize the immense wealth of data we have lost to time. As data storage becomes cheaper and cameras become smaller, the possibility of a comprehensive memory prosthesis will emerge in our lifetimes. Imagine being able to rewind and review every moment of your life without having to rely on memory. Find your car keys by reviewing the recording of the last time you had them rather than tearing up your house exhausting all the possibilities.

Psychology already knows how much our perceptions and emotional states can change the way we remember things. The capability to review any moment in our lives would allow us to analyze our experiences objectively. When our mind plays tricks on us, we can check the recording to determine if we saw what we think we saw. Imagine the implications for domestic spats.

We could also return to a moment in time, such as our first kiss or learning to ride a bicycle, evaluating it from a wiser perspective, and gaining even more wisdom in the process. Such a device will inevitably lead to very interesting legal challenges. Just as diaries and journals are sometimes sequestered in courts as evidence, an individual’s personal webcam would certainly be admissible. The recording would become deleterious for the criminal, but advantageous for the victim. The camera would serve as a neutral witness for juries and judges to review its third-person account of events.

Is it possible to record every moment in a person’s life? If one hour of video on a DVD consumes 2.5 Gbytes, multiplied against the 600,000 hours of the average human lifespan, then we will need 1500 Terabytes to record a lifetime. We will soon have DVDs with a storage capacity of one terabyte. I envy the future human who possesses a bookcase filled with DVDs chronicling their lifetime, or whatever storage device becomes the next standard.

There is one important constraint also needing consideration; we are only recording two senses, hearing and seeing. We’re leaving out taste, touch, and smell. We’ll be able to review ourselves eating the escargot, but we won’t know what it tasted like. People who wish to capture an approximation of the missing senses would need to speak to their memory prosthesis, describing the missing sensations. If you find people talking to their bluetooths in grocery stores a bizarre site, as if they were talking to themselves instead of someone on the phone, imagine someone talking to their memory prosthesis, describing the flavor of anchovies, the scent of a lavender, or the feel of silk. It would certainly improve people’s language skills, giving them an incentive to adopt a more descriptive lexicon for our three undervalued senses, and exercising the right brain.

Just some futurist speculation on a technology we will see in our lifetimes, and the implications for our culture. Feel free to contribute your own perspectives.

Many of these numbers come from Professor David Wishart’s slide presentation Between Biological and Digital Memory.

Thomas K. Landauer “How Much Do People Remember? Some Estimates of the Quantity of Learned Information in Long-term Memory” Cognitive Science
10, 477-493, 1986