The Distracted Mind: Ancient Brains in a High-Tech World (The MIT Press)

by Adam Gazzaley

You are at the dinner table with your family, the television blaring in the background, and everyone has a phone sitting on the table that they constantly pick up, check the screen, tap a few times, and then put down face up so they don’t miss incoming messages. This is followed by clumsy attempts to figure out what you missed in the conversation and reengage as best as possible.

The magnitude of the impact is even greater for those of us with underdeveloped or impaired brains, such as children, older adults, and individuals suffering from neurological and psychiatric conditions.

“Interference” is a general term used to describe something that hinders, obstructs, impedes, or largely derails another process.

also referred to as “noise.”

The interference can either be generated internally, presenting as thoughts within your mind, or generated externally, by sensory stimuli

two distinct varieties—distractions and interruptions—based on your decision about how you manage the interference.1

the act of sitting down with a friend to catch up on each other’s lives. This seems like a relatively straightforward goal. But, even without the presence of modern technology, four types of interference threaten to derail you from accomplishing this sort of goal: internal distraction, external distraction, internal interruption, and external interruption.

Distractions are pieces of goal-irrelevant information that we either encounter in our external surroundings or generate internally within our own minds. When it comes to distractions, our intentions are very clear—we wish to ignore them,

Interruptions are the other major source of goal interference. The difference from distractions is that interruptions happen when you make a decision to concurrently engage in more than one task at the same time, and even if you attempt to switch rapidly between them.

Interruptions such as these are often referred to as “multitasking,” defined as the act of attempting to engage simultaneously in two or more tasks that have independent goals.

when it comes to what actually occurs in your brain, the term “task switching” is a better description.

What distinguishes distractions from interruptions are your intentions about how you choose to manage them; either you attempt to ignore them and carry on with your original goal—distraction—or you engage in them as a simultaneous, secondary goal—interruption.

All complex systems are susceptible to interference,

the human brain, undeniably the most complex system in the known universe, it should thus come as no surprise that it is extremely sensitive to interference at many levels. Indeed, the reason why goal interference in particular is so prominent in our lives is the inherent complexity of our goals and the limitations we have in fulfilling them. Our ability to establish

The sheer magnitude of our impressive goal-setting abilities has resulted in the conditions necessary for goal interference to exist in the first place.

Our ability to effectively carry out our goals is dependent on an assemblage of related cognitive abilities that we will refer to throughout this book as “cognitive control.” This includes attention, working memory, and goal management.

Our cognitive control abilities that are necessary for the enactment of our goals have not evolved to the same degree as the executive functions required for goal setting.

Our cognitive control is really quite limited: we have a restricted ability to distribute, divide, and sustain attention; actively hold detailed information in mind; and concurrently manage or even rapidly switch between competing goals.

In many ways, we are ancient brains in a high-tech world.

We can visualize this as a conflict between a mighty force, represented by our goals, which collides head on with a powerful barrier, represented by the limitations to our cognitive control.

a tension between what we want to do and what we can do.

According to a 2015 report by the Pew Research Center, 96 percent of all US adults own a mobile phone, and 68 percent own a smartphone. Among US smartphone users, 97 percent of them regularly use their phone to send text messages, 89 percent use it to access the Internet, and 88 percent send and receive email.5 Worldwide estimates are that 3.2 billion people, 45 percent

these technological innovations have been accompanied by a shift in societal expectations such that we now demand immediate responsiveness and continuous productivity.

Several studies have reported that US adults and teenagers check their phone up to 150 times a day, or every six to seven minutes that they are awake.9 Similar studies in the UK have found that more than half of all adults and two-thirds of young adults and teens do not go one hour without checking their phones.

Interference-inducing behaviors involve intentionally placing oneself in a distracting environment (e.g., going to a crowded, noisy coffee shop to write a book)

fascinating question remains—why do we do it, even if we understand that it degrades our performance?

physiological signs of increased arousal are associated with switches between multiple types of content on a single device.12 In regard to rewards, researchers have shown that novelty is associated with reward processing in our brains.13

In addition, the act of receiving an earlier reward is often more highly valued, even if a delayed reward has greater overall associated value.14 This phenomenon, known as the “temporal discounting of rewards,” is a strong influence on impulsive behaviors and so may also play a role in the inherent drive to seek the immediate gratification that comes from switching to new tasks sooner rather than later.

We engage in interference-inducing behaviors because, from an evolutionary perspective, we are merely acting in an optimal manner to satisfy our innate drive to seek information. Critically, the current conditions of our modern, high-tech world perpetuate this behavior by offering us greater accessibility to feed this instinctive drive and also via their influence on internal factors such as boredom and anxiety.

The answer is that at our core we are information-seeking creatures,

Macaque monkeys, for example, respond to receiving information similarly to the way they respond to primitive rewards such as food or water.

Thomas Hills, a pioneer of this perspective, describes, “Evidence strongly supports the evolution of goal-directed cognition out of mechanisms initially in control of spatial foraging but, through increasing cortical connections, eventually used to forage for information.”

In 1976, evolutionary biologist Eric Charnov developed an optimal foraging theory known as the “marginal value theorem”(MVT), which was formulated to predict the behavior of animals that forage for food in “patchy” environments.

The key factor in the model is designated in the figure as the “resource intake curve.” It reflects the diminishing returns of foraging in the same patch over time (represented by the curved line). The cumulative resource intake does not increase linearly or eternally as time foraging in the current patch increases (i.e., the nuts run out).

let’s consider the MVT and replace foraging for food resources with foraging for information resources, and insert you as the information-foraging animal. Here, the patches are sources of information, such as a website, an email program, or your iPhone.

returns of resources over time as you gradually deplete the information obtainable from them, and/or you become bored or anxious with foraging the same source of information. And so, given both your inherent knowledge of the diminishing resources in the current patch and your awareness of the transit time to reach a new information patch, you will inevitably decide to make a switch to a new information patch after some time has passed.

the wonder of the mind is to fully appreciate that it is the essence of every emotion you feel, every thought you have, every sensation you experience, every decision you make, every move you take, every word you utter, every memory you store and recall … in the truest sense, it is who you are.

despite all this, the human mind has fundamental limitations when it comes to our ability to use cognitive control to accomplish our goals.

These primordial lives were dominated by an uninspired sequence of events: detectors on their surface assessed chemical gradients of nutrients and toxins in the surroundings that guided the direction of their locomotion. This was essentially a simple feedback loop that transformed sensation into movement.

basic function remained at the core: to sense positive and negative factors in the environment and to use that information to guide actions.

The perception-action cycle is fed by sensory inputs from the environment—sights, sounds, smells, and tactile sensations—whose signals enter the brain via an expansive web of specialized nerves.

These patterns are sculpted by processes of divergence, convergence, amplification, and suppression, which form complex representations of the external world, or perceptions.

The perception-action cycles of primitive brains were essentially automatic, reflexive loops.

During this pause, highly evolved neural processes that underlie our goal-setting abilities come into play—the executive functions.

If a child pinches your arm, you will invariably recoil, fulfilling the pain-withdrawal reflex. But you are then unlikely to strike back. You are able to pause, engage in goal-setting processes, evaluate the act as nonmalicious and the young perpetrator as a nonthreat, to reach a decision that a violent response is unwarranted and inappropriate.

Children with underdeveloped goal-setting abilities often do strike back in this situation, much to the dismay of parents around the world.

Neuroscience research has helped us understand that perception is not a passive process; sights, sounds, and smells of the world do not simply flood into our brain. Rather, the inward flow of information is sculpted and pruned by goals in much the same way that our actions are, resulting in our perceptions being an interpretation of reality and not a veridical representation.

animal behaviors are often attributed human-like goals. This is an act of anthropomorphization—the assigning of human qualities to other entities.

Consider the dramatic stories that emerged following the 2004 Indian Ocean earthquake off the west coast of Sumatra. This undersea earthquake resulted in a tsunami claiming the lives of approximately 230,000 people in fourteen countries. Interestingly, reports noted that as humans stood transfixed, or even approached the receding tide that preceded the tsunami out of curiosity (top-down goals), other animals took off to higher grounds before the destruction ensued.