After spending decades in the HDD industry, I came to believe that even the slightest loss of stored data was so catastrophic as to justify a hurried team meeting and a frantic search – using the latest high-tech tools – for the root cause. I never hesitated to buy extra storage for my own personal data so that I could always have a backup. Computer memory stores data as a string of 1’s and 0’s, typically represented by either tiny, magnetized regions on a surface, or as electrical charges on floating gate transistors.   Storage integrity is affected by things like temperature, humidity, and mechanical shock. The physics is straightforward, but the possibilities for failure are many.

Of late, I have begun to ponder memory loss of a different kind. It seems that if you sometimes enter a room only to forget why you went there, it is normal. If you misplace your car keys and find them on the bathroom counter, that too is normal. If, however, you find your keys in the freezer, you may need to summon a different team with a separate set of tools to figure out what is going on. The human brain has around 86 billion neurons, each with thousands of connections. A process known as synaptic plasticity alters the strength of these connections, forming the basis for learning and memory. Unlike with digital devices, storage is analog and influenced by emotion, context, and experience.

With all those neurons and connections buzzing away, you would think we could remember pretty much everything, but the design wasn’t meant for that. According to a 2009 report by the Global Information Industry Center at UC San Diego, we are exposed to 34 Gigabytes (nearly 12 hours’ worth) of information on a daily basis. Cognitive psychologist George Miller, in a 1956 paper on memory capacity, suggested that we can only keep 7 things (plus or minus 2) in mind at a time. While researchers are still debating the number, most suggest that it is probably smaller rather than larger. Our brains are mindbogglingly miraculous in function, but they are also selective. <continue reading>