A few weeks ago I was enjoying some incredible sesame seared tuna in Key West with a great crew. The setting was absolutely stunning; great conversation, atmosphere, weather the works! The conversation drifted around all afternoon but one particular statement caught my attention - ‘I multi-task all the time’.

Some well humoured competition between the guys and girls followed with the boys being put firmly in their place by the girls on this particular topic! The examples provided included studying whilst also watching a film or holding a conversation whilst watching something on tv etc. There was a strong belief by some of the group that they could indeed carry out two independent tasks at the same time.

Whilst the consensus amongst the group was that this activity was dangerous some still believed they could concentrate on both tasks at the same time with little degradation in ability for either task.

I challenged a member of the group to demonstrate their multi-tasking abilities. Initially, I asked them to count to 26 as fast as they could and then to recite the alphabet as fast as possible - both of these tasks individually took only a few seconds. I then asked the same individual to combine the two tasks in sequence – A.. 1.. B.. 2.. C.. 3.. etc. which took more than 10 times as long to complete.

Individually counting to 26 and reciting the alphabet are simple tasks but combining them is not a learned skill and so we mentally separate the tasks. At the beginning it is quite easy but as the alphabet progresses most individuals slow down.

To understand why this is so much more challenging we must consider how the brain processes information. Modern computers state that they have quad cores (or more) meaning they can deal with several channels at once - in this example counting would be one channel and the alphabet would be another. The human brain only has a single channel – imagine a beam of light from a torch where only the item [task] in the beam can be processed.  The brain can only focus on and complete one activity at a time therefore if we want to complete 2 tasks simultaneously we must share our brains processing power [our attention] between the two tasks and switch back and forth between them; this switching also incurs a time penalty which will extend overall task duration. Depending on how many tasks we are conducting simultaneously and how much time we allocate to each will determine the relative success of, and time taken to complete, each task.

We can also look at additional tasks as distractions where one task is taking up valuable processing power – driving and operating a mobile phone for example. For an experienced driver, the mechanics of actually controlling the vehicle are learned motor responses that the subconscious can deal with however, monitoring the vehicle and other road users is a higher level function which requires processing power from our ‘single channel’ brain. If we add another task such as talking on/operating a mobile phone the result is the same as when we count and recite the alphabet together – our attention is constantly being shared between two tasks with our performance being degraded in each.

Many will likely have seen this video however, it demonstrates this point incredibly well. If we imagine talking on our mobile phones to counting the passes and driving to be watching the overall scene it is clear why adding tasks to our workflow can be so detrimental to success or even dangerous.

To minimise the risk of mistakes during safety critical activities we must prevent distractions as far as possible. In aviation we ensure a sterile cockpit area during certain phases of the flight – no extraneous conversations etc so that we can concentrate on those most essential tasks.  I do the same thing when I am studying – I create an environment that means all my attention is focused on the task at hand [learning] and not shared with other tasks/distractions e.g. email, social media or the TV!

It is impossible to remove all distractions, especially in highly dynamic environments, but we should strive to design our processes and procedures such that our workload is reduced to just those tasks which are essential at critical phases. If we are able to design processes and procedures with an understanding of our limitations we can reduce the chances of a catastrophic system failure and increase the likelihood of a repeatable successful outcome. If we allow distractions into our systems we may miss those most critical pieces of information [the gorilla] that could have helped lead to a successful outcome.