The ability to multitask is arguably the most desirable skill to possess in today’s day and age. Whether in an academic or a professional setting, one’s ability to manage a large task load and high stress situations is seen a positive attribute.
But despite our cultural preference, our internal biochemistry does not thank us for the ever-increasing amounts of stress we overload ourselves with.
Seemingly simultaneous awareness and processing of information actually happens in a matter of incremental windows. During these few seconds, the brain takes in the stimuli from the environment as a block and subsequently processes the data in the next window.
What really ends up happening when we multitask is that at any given time, one subject occupies the foreground of our consciousness while the other tasks stay in the background until they are given access to the central processor.
What we refer to as multitasking is really more similar to channel surfing. Rather than actually being able to focus on a variety of things at once, we can really only give our attention to one thing at a time.
The human brain cannot simply double its efforts to concentrate on different things or to solve multiple problems at the same time. Contrary to popular belief, multitasking only saves time when doing relaxed or mindless tasks.
Our attention control processes are mediated by the prefrontal and parietal lobes. The prefrontal cortex is the executive part of the brain. It helps to assess and prioritize tasks and it tags the spot at which a task has been interrupted so we can return to it later.
This system typically operates extraordinarily well. But when we try to regularly multitask in our everyday lives, it causes disjointed thinking. Connections that would normally be formed in the cognitive process are lost, and no lasting neuronal connections are created from the information processed.
As many people have experienced, when we attempt to multitask indefinitely, it becomes difficult to process information and concentrate. The human brain was not built to sustain continuous partial attention for extended period of time. The sense of self-control we normally possess begins to break down, and we tend to get frustrated when doing many things that require attention.
The brain needs to fully process the stimuli it receives, which it cannot do effectively with signal overload or signal disruption.
Under intense pressure, our brains signal the adrenal gland to release the stress hormones, adrenaline and cortisol. In the short term, such as taking an exam, these hormones help increase memory and boost energy levels.
In the long term though, they impair cognition, lead to depression and alter the circuitry in the hippocampus, amygdala and prefrontal cortex, the areas of the brain that control mood and thought. Brain cells in the hippocampus, which is known for its role in the formation of new memories and accessing and building connections to existing memories, are affected and the damage from the stress makes it difficult for a person to acquire new skills and learn new facts.
Biochemical consequences of stress in our everyday lives is truly worth emphasizing. As most of us have felt at some point or another, our bodies and brains cannot sustain high levels of stress indefinitely and we eventually crash. Rather than celebrating the amounts of stress we can handle, we should instead concentrate our efforts on reducing that stress, ultimately facilitating better brain function.
