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How Bias Changes the Brain

Updated: Sep 1, 2023

Every day the news is filled with stories about crime, terrorism, crime, violence, injustice, drug abuse and oppression. Serious news has been redefined as the “newest bad news”. And it’s not just the A-block on news shows. Newspapers, opinion pieces and cover stories on magazines deliver enough bad news to make one wonder if we’ll survive another day.

Have you ever wondered how all of that bad news affects your brain? Not your feelings -- but your brain chemistry? Recent studies maintain that heavy news watchers experience a misperception of risk, higher anxiety, lower moods, learned helplessness, iincreased cortisol levels, and greater activation in the survival brain. They are even fatalistic. We can debate all day long whether the world really is getting worse, but neuroscientists agree that the nature of news interacts with the nature of cognition in a way that makes us believe it is.

Psychologists Amos Tversky and Daniel Kahneman maintain this is the “availability heuristic” at work. The availability heuristic is the brain’s natural tendency to estimate the probability of an event happening by the ease with which examples come to mind. When the brain taps into a memory for reasons other than frequency such as how recent, how gory, or how unusual it is, the natural default is to overestimate how likely it is.

An easy example is the fear of flying. Car crashes kill far more people than plane crashes. Yet, the fear of flying, or aerophobia is in the top 10 phobias of all time” list and affects nearly 6.5% of the world’s population. Plane crashes are “breaking news” while car crashes are often not covered at all. If it bleeds, it leads.

With 24/7 access on every device, t’s impossible to escape the negative news coverage completely. We live in a world that desperately needs more compassion, tolerance, and kindness. However, recent research from the University of Michigan and the University of Rochester Medical Center reports that compared to the late 1970s, empathy among students has declined by more than 40%.

Compassion Fatigue

Sociologists maintain that the saturation of negative news has resulted in compassion fatigue. Also known as secondary traumatic stress (STS), compassion fatigue is a condition characterized by a gradual lessening of compassion over time. It is common among people who work directly with trauma victims such as health care professionals, police officers, paramedics, and even teachers. But, now we are seeing it regardless of occupation. Symptoms include hopelessness, failure to experience pleasure, constant stress and anxiety, sleeplessness or nightmares.

Negativity Bias

We can blame some of it on the media, but there is some neuroscience behind it, too. Namely, a cognitive bias that affects all of us.  Negativity bias refers to the idea that negative thoughts, emotions or social interactions have a greater effect on us than do neutral or positive things.  From an evolutionary standpoint, we have survived and evolved thanks to the negativity bias. It was the brain's built in way to keep us cautious of all the environmental dangers around us. Through evolution the bias has become so automatic that it can be detected at the earliest stage of the brain’s information processing.

The negativity bias has been explored in a variety of cognitive functions such as attention, learning, memory, and decision-making. For example, studies show that when we are presented with a decision in which we can either gain something or lose something, it’s a natural tendency to consider the potential loss more than the potential gain.

Jonathan Haidt, social psychologist, explains in his book, Happiness Hypothesis, why we have a preference for the bad over the good:

“This principle, called ‘negativity bias,’ shows up all over psychology. In martial interactions, it takes at least five good or constructive actions to make up for the damage done by one critical descriptive act. In financial transactions and gambles, the pleasure of gaining a certain amount of money is smaller than the pain of losing the same amount. In evaluating a person’s character, people estimate that it would take twenty-five acts of life-saving heroism to make up for one act of murder. When preparing a meal, food is easily contaminated (by a single cockroach antenna), but difficult to purify. Over and over again, psychologists find that the human mind reacts to bad things more quickly, strongly, and persistently than to equivalent good things. We can’t just will ourselves to see everything as good because our minds are wired to find and react to threats, violations, and setbacks. As Ben Franklin said, ‘We are not so sensible of the greatest Health as of the least Sickness.’”

But there is good news! There is a way to change the brain’s negativity bias. Simply, it's just a matter of training our brains for positivity, to actively become more attuned to positive emotions such as joy, interest, contentment, pride and love. Science claims that for a positive experience to get into our long-term memory we should hold it in our field of attention for at least 10-20 seconds, if not it disappears.

Experience-Dependent Plasticity

Taken one step further, we have the power to take that 10-20 second experience and physically change the brain. Specifically, it’s called experience-dependent plasticity.

All mental activity—sights, sounds, thoughts, feelings, conscious and unconscious processes—is based on underlying neural activity. But brain imaging technology shows that intense, prolonged, or repeated mental and neural activity will alter the structure of the brain. In other words, neurons that fire together wire together and mental states become neural traits.

One famous study used brain imaging technology to study the brains of London cab drivers. If you’ve ever been to London, you know that the streets and numbers don’t follow a logical grid pattern. Black Cab drivers memorize the city's layout by driving it and paying attention to landmarks and buildings. Scientists discovered that the connections in their visual-spatial cortex were thicker and larger because they used that part of the brain day in and day out.

Other studies have examined the brains of people who practice mindfulness. They are thicker and stronger inthree key regions: prefrontal areas behind the forehead that control concentration and focus; the insula, the region responsible for self-awareness, and interpersonal experiences, and the hippocampus which manages memories. What is fascinating about mindfulness is that it doesn’t just change affect the neural structure, but it also alters the genetic structure. People who routinely practice relaxation will increase the activity of genes that calm down stress reactions.


So what does experience-dependent plasticity have to do with the negativity bias? If intense, prolonged or repeated experiences alter the neural structure, we can create those experiences with intention and control those changes. We have the power to focus on the positives or the negatives. The choice we make will change the brain in a way that keeps the survival brain working or strengthens the thinking, rational brain.

Neuroscientists call this self-directed neuroplasticity and it’s actually pretty simple. If you focus on self-criticism, worries, hurts, and stress, over time your neural structure will become wired for reactivity, anxiety, anger, and sadness. On the other hand, if you focus on positive people and events, pleasant feelings, or your own good qualities, then your brain will be wired for optimism, strength and resilience.

This isn't new age nonsense. Numerous studies and brain scans have shown that intentional emotional experience training actually does sculpt a better brain. The key is to create and focus on more emotionally positive reactions than negative ones.

So today, use your mind to change your brain to change your mind and wire happiness into your brain.

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