How neuroscience is rewriting the art of war

When military historians attempt to make sense of a conflict like the Second World War, they tend to examine the external conditions of battles, such as which army possessed the most advanced weapons, experienced generals, favorable terrain, and reliable supply lines.

Nicholas Wright, a neuroscientist and longtime national security adviser for the British and American militaries, prefers to focus on the internal conditions: What’s happening inside people’s brains. How do people respond to fear and stress? How do soldiers assess risk or make life-or-death decisions?

As he notes in the introduction of his new book, Warhead: How the Brain Shapes War and War Shapes the Brain, common explanations for why the Allies managed to defeat the Axis often boil down to some combination of “Russian manpower and American manufacturing.” But this familiar story leaves many important facts: “Germany almost won; Britain didn’t lose; Russian will didn’t collapse; and Americans learned from ingenious and effective adversaries.”

According to Wright, “none of that can be understood without the central weapon of war, the human brain.” The same is true of modern warfare. While no longer waged exclusively with rifles and rockets, but also AI, drones, and cyberattacks, today’s wars nonetheless influence how we think, feel, and act on the battlefield.

In Warhead, Wright explains how armed conflict impacts every part of our brain, from the instinctive reflexes of our reptilian brainstem to the cognitive and metacognitive functions of the prefrontal cortex. He also reveals how this knowledge has been leveraged in past and present wars, and how it could be leveraged in the future to enhance the offensive capabilities of soldiers or protect civilians from foreign threats.

I recently spoke with Wright to discuss the extent to which violence and conflict are intrinsic to our evolutionary history, whether humans can ever achieve world peace, and how authoritarian regimes arise from a biological fondness for strong, efficient leadership. 

(The following interview has been edited for length and clarity.)

Big Think: What motivated you to write this book, and what makes the intersection between neuroscience and national defense so relevant today? 

Wright: Nowadays, many people want to know why there are so many wars, and what we can do about them. To help answer these questions, we can use the latest research on what has always been the central weapon of war — and instrument of peace — the human brain. 

Consider May 1940. The German army had fewer men, guns, tanks, and planes than France’s defenders. But in the 1920s and 1930s, German military professionals had studied how they could harness the human brain’s capacities for shock, creativity, guile, willpower, daring, and skill to win wars by surprising and deciding faster than the enemy.

Big Think: How has the scientific understanding of the brain in conflict developed over time?

Wright: The brain has always been central to the most insightful thinking on warfare, whether that’s ancient China’s Sun Tzu, who prized deception and self-knowledge, or early 19th-century Prussia’s Carl von Clausewitz, for whom war was a clash of wills. That said, the scientific study of the brain really took off in the late 19th century.

One idea that greatly advanced our scientific understanding is that the brain employs models that link senses to actions, thereby helping us achieve our goals. Knowledge of these models can challenge what seems common sense. It seems common sense that light hits your retina, is converted into signals, and is then processed by the brain into images. However, that’s not completely true: Our perception is controlled by our expectations. However objective our perception may seem, we can only ever perceive part of reality.

Carl von Clausewitz famously described the “fog of war.” As societies industrialized, scientists applied their understanding of perception to enhance that fog. As a psychology manual for the U.S. Armed Forces from 1943 put it: “Take advantage of another man’s brain, use its own rules to deceive it, to make it perceive something that is not real.” Exploiting our brain’s expectations was the core target, and it remained so as militaries digitized.

Big Think: What are some of the most profound and effective ways our understanding of the human brain has shaped the way we conduct warfare, and how the brain may shape warfare in the future?

Wright: I can give you three items from my own direct experience advising the Pentagon. First, enhancing “information operations” to defend populations from attack by those seeking to sow discord. What are the features of audiences, messages, and messengers on social media that are most effective at influencing people? The brain helps us list them. 

Second, nuclear weapons. While writing this book, I met with analysts from U.S. Strategic Command, which runs the U.S.’s nuclear planning. What they often find most useful is insight about how humans think, as their job is essentially to understand the brains of key individuals like Xi Jinping, Vladimir Putin, and Kim Jong Un.

Third, how humans and machines (including AI) can work together. You can have the best tech in the world, but if it doesn’t work well with the humans who have to use it, you’ll lose. If an AI and a human are working together, they must communicate effectively, and that requires understanding the human side as much as the AI side.

Big Think: Could you explain the neuroscience behind the “will to fight,” a concept often discussed in literary and philosophical contexts as opposed to scientific ones?

Wright: Fear is so powerful because almost no human wants to die. Self-preservation is a basic feature of life. And yet, running away is often not the best way to succeed or survive, and so humans, like most other animals, evaluate and manage risks.

Risk assessment involves not only the amygdala but also the insula, which lies next to it. The insula helps explain another reason why soldiers remain in the fight: the powerful social bonds with members of their unit, who they don’t wish to leave or let down.  

A good analogy is that of a concert orchestra. The orchestra’s sections — strings, percussion, and so on — work together, and the output of any one section alone cannot produce a symphony.

In the brain, “bottom-up” systems give the “orchestra” abilities, such as reacting to pain, vital drives like hunger, and visceral instincts like the emotions of anger or fear. More cognitive, “top-down” systems, arising from higher brain areas like the prefrontal cortex, give abilities such as control and reflection, or [the ability to] think about thinking. Humans need both.

Big Think: Are qualities that would be helpful on a battlefield, such as fear management and risk assessment, inborn or acquired?

Wright: Qualities like fear management can be developed by training. For example, soldiers who were studied during parachute training showed dramatic stress responses within minutes of their first jump, but in later training jumps, that stress changed to thrill. That’s why training is crucial. [It helps] avoid the kind of moral collapse that occurred among French soldiers in 1940 and helps people cope with the unexpected.

Overall, training is probably more important than selective recruitment, although recruitment can be necessary for specialists with specific areas of expertise. Such expertise requires an innate ability, thousands of hours of practice, and the ability to learn effectively. All three are necessary and none is sufficient on its own.

Big Think: If perfectly peaceful societies are incompatible with human nature, what practical steps can nations take to foster peace and avoid war? Instead of chasing utopias, how can we use self‑knowledge to build something more durable?

Wright: A prime reason for my optimism is that human self-knowledge is cumulative. Self-knowledge can help us avoid oversimplistic ideas that are wrong or incomplete. Steven Pinker was probably right when he argued that the arc of history tends towards peace. But that’s not enough to keep us safe because wars do happen, and they don’t win themselves.

Other thinkers, like Robert Sapolsky, hope that we can stop wars by persuading enough people that they are bad and pointless. Reconciliation is as natural as conflict — but pacifism, or being completely unwilling to defend yourself, while aiming for peace as an end, provides no means of getting there.

Others still focus too exclusively on building ever more powerful militaries, or using them ever more aggressively, regardless of the risks they run. 

We can reduce the chances of conflicts and wars escalating. [To do so], we need to understand why humans fight, lose, and win. Wisdom is seeing the bigger picture of ourselves in the world, so our chosen actions help us live better.

Big Think: Some argue that the centrality of conflict and aggression in human evolutionary history is overstated and even misconstrued. How do you respond to that line of thinking, both as a neuroscientist and a Pentagon advisor?

Wright: Is the human story one of relentless violence only? No. There is art, beauty, love, happiness, construction, invention, wonder. But violence is part of us, too. Our closest ape relatives, like chimps and bonobos, show a fair amount of violence, as did many groups of hunter-gatherers. Since states first popped up, history has been full of wars.

Wiser people don’t just look away from things that are unpleasant, especially not when the stakes are high. Some overstate the role of violence, others understate it. As I warn in the book, both can be dangerous.

Big Think: Warfare evolves. If the brainstem helps us understand conflict in its most primitive forms, which regions of the brain will shape how we navigate the wars and military technologies of the future?

Wright: I would push back a little and say our entire brain will shape our military and technological futures. 

Take the hypothalamus. Located at the top of the brainstem, it’s crucial for sleep, thirst, hunger, warmth, and sexual reproduction, and work on this organ could yield huge prizes for humanity. Astronauts traveling to Mars will have to survive for months on a tiny spaceship with minimal food, endure microgravity where their bones and muscles waste away, and suffer from cosmic radiation bombardment. The hypothalamus helps with all those challenges in animals.  

The higher parts of the brain will be crucial, too. For example, human-machine interfaces will increasingly use augmented reality that superimposes information on our vision to help us act — not because augmented reality is a Silicon Valley fad, but because it’s a natural extension of how we perceive. 

The book’s journey through the brain ends at the frontal pole, a region involved in self-reflection — thinking about thinking. How self-reflection operates matters because it will always be needed to make wiser choices about our toughest challenges. [For instance], no human or AI can be infinitely wise. But the more we discover about our brain’s machinery for wisdom, the more pathways open up to building wiser AI. 

Big Think: You’ve written about the neuroscience of war. What about the neuroscience of authoritarianism? How do such regimes exploit certain brain functions or cognitive tendencies?

Wright: Most social species self-organize into social hierarchies because doing so can help decrease aggression and conserve energy in the group. Strong leadership also enhances effectiveness: a group of doctors treating an emergency trauma patient needs someone to lead them, or things might get missed.

The challenge for free societies is that the effectiveness of leadership and social hierarchies always affords the possibility for authoritarianism. Charismatic and successful military leaders like Douglas MacArthur, who refused to follow President Harry Truman’s orders during the Korean War, will always hold considerable power due to the prestige and dominance that militaries bring.

Big Think: You mention that the hippocampus — linked to memory and spatial navigation — shapes how humans fight over territory and historical grievances. How do you think collective memory operates on a geopolitical scale? When people in power rewire a society’s collective memory, are they literally rewiring our brains?

Wright: Yes! And it’s not just people in power who shape the contents by which our societies function. We all shape human memories that are physically encoded in our brains. I have seen patients where specific brain disorders affect specific types of memories. Losing memories leaves us adrift because we remember not for the sake of the past, but for the future, so we can create a landscape of possibilities to navigate.

To be useful, our memories are dynamic rather than static, which is why forgetting is an active process, a feature and not a bug. Collective memories are dynamic, too. The stories we tell about ourselves and events, including war, are shaped by our social interactions: talking, reading, watching TV, or movies. 

In Britain and the U.S., we have largely forgotten what many who actually fought or led in World War II knew: The Germans fought better on land than the British and Americans until near the war’s end. French collective memories altered considerably after World War II, converting a story of collaboration after June 1940 into one of resistance.

Chinese memories of World War II have changed even more, and these changes matter today. In the book, I describe how China’s involvement in World War II was part of a series of civil wars, and how, during Communist leader Mao Zedong’s rule, the war was told as a story of communism’s rise.

Since Xi Jinping assumed power in 2012, Chinese stories have increasingly included nods to Chinese nationalist (not just communist) soldiers fighting bravely, thus placing a strong, victorious, and morally righteous China at the forefront of the postwar global order.

Big Think: Deterrence theory in geopolitics assumes people act rationally. Yet neuroscience shows us that perception is biased, emotions hijack reasoning, and threat‑detection systems, like the amygdala, can overreact. As such, should we rethink assumptions behind, say, nuclear or cyber deterrence?

Wright: No Western country can destroy all of Russia’s or China’s nuclear weapons, meaning that — whatever others do to them — they can strike back and kill millions. What we can do is influence their decision-making to deter them from using nuclear weapons and to influence their escalation if war happens. 

That’s why U.S. Strategic Command officials are interested in cognitive insights, how humans think. They want to influence how others think, as societies or as individuals. We have to put ourselves in the other’s shoes, to anticipate how the other will decide to act (or not act), so that we can better make peace with them, deter them, and — if we must fight — outwit them.