Sample Chapter: Life and Death Design
This is a sample chapter from Katie Swindler‘s book Life and Death Design: What Life-Saving Technology Can Teach Everyday UX Designers. 2021, Rosenfeld Media.
Chapter 1: A Designer’s Guide to the Human Stress Response
The human stress response is key to our survival as a species. A human without a stress response would never avoid pain, defend themself from an attack, or invent solutions to overcome problems. Stress is unpleasant, but that unpleasantness has a purpose. It’s by design. It’s meant to drive humans away from harmful things. Stress is a powerful motivator and a major driver of human behavior, which is why it’s critical that designers of all types of products, services, and experiences understand the ins and outs of the human stress response.
Stress takes many forms. There’s eustress, which is a healthy, beneficial type of stress experienced when engaging in enjoyable, challenging experiences. There’s also hypostress, caused by boredom, that drives the person to take action to relieve the tedium. But when most people think of stress, they think of distress, which is a stress response in reaction to negative or overwhelming things. Under the umbrella of distress are the two most common types of stress that scientists study: acute stress, stress in response to a momentary crisis that quickly passes, and chronic stress, which lasts weeks, months, or years.
Although the causes, severity, and durations of different types of stress responses may vary, at its core, the basic biology of stress is always the same. The stress response has stood the test of evolution for millions of years with the core processes, hormones, and reactions remaining largely unchanged from the time of our earliest mammalian ancestors. In fact, the core difference between the human stress response and the stress response of animals is not a change to the core functionality at all but rather an additional feature—logic. The development of the prefrontal cortex, the part of the brain that handles logic and reason, gave humans a way to interrupt, redirect, and suppress their instinctual stress reactions. This additional layer of control means that humans’ reaction to stress is significantly more complex than that of other animals, but when you understand the driving forces at the core of the stress response, patterns of behavior emerge. It is through understanding these patterns and better anticipating users’ needs in these moments of crisis that designers can make a positive impact.
This book will focus primarily on the acute stress response, because the effect of stress on human behavior is most pronounced in moments of peak stress. The extreme reactions that humans experience during acute stress make it an ideal teaching tool: it’s easier to break down, share relevant examples, and establish applicable techniques for designers. And, once you understand how to create designs that support users through an acute stress response, the lessons can be adapted and applied to any other type of stress.
What Happens in a Moment of Acute Stress?
During an acute stress response, the body diverts energy from some physical and mental functions to supercharge others. These changes favor qualities that are associated with “primal” attributes—strength, speed, and aggression. This response sharpens senses, intensifies focus, and drives fast, intuitive decision-making. But these advantages come at a cost: the loss of fine motor control, a suppression of impulse control, a degradation of rational thought and higher-order thinking like reading and math, and a loss of empathy and creativity. The things that people value most about their humanity are momentarily set aside in a raw bid for survival.
Some industries have invested heavily in research around designing for the human stress response. For example, designers who make airplane dashboards, weapon interfaces, and medical devices understand that their users are likely going to be in intense, high-pressure, life-and-death situations when using their products, and they invest in the research necessary to ensure that their products allow humans to function at peak performance while using them. But flying planes, fighting wars, and performing surgeries aren’t the only situations where humans experience stress, far from it.
Consider the visceral reaction someone might have to logging in to their banking app to find their account unexpectedly overdrawn, or receiving the devastating news through a social media app that a friend has died. Or think about how often people lose their temper at chat bots or threaten to throw their laptop across the room in frustration over some technical issue.
Of course, digital interfaces aren’t just the cause of acute spikes in stress. They are also the place where people often turn for help during a moment of extreme distress—for example, dialing emergency services after a car crash, checking for updates on an approaching storm, frantically Googling for medical information to determine if they should take their child to the ER, or ordering a taxi to escape a date that’s turned threatening.
Because technology has become so integrated into every aspect of people’s lives, it is a near certainty that, over the course of your career as a digital designer, you will design products that will be used by someone during or directly following a moment of crisis, even if that is not the product’s primary intent. By studying and understanding the human stress response, you can better anticipate people’s needs and behaviors in those moments, allowing your product to support them in the moments that really matter.
In this chapter, we’re going to start with an overview of the acute stress response, which includes five major stages:
- Startle re1ex
- Intuitive assessment
- Fight, flight, or freeze
- Reasoned reaction
- Recovery
In order to illustrate all the steps of the response, we’ll follow the tale of a woman named Amy (named for the neurological star of the stress response—the amygdala) as she experiences a frightening event. Amy and the following story are fictional, but the science underlying Amy’s adventure is as real as it gets.
Amy’s Accident
Amy is about to have a very bad morning. She’s driving to work—it’s a route she’s followed a hundred times before. She’s driving on the kind of mental autopilot only daily commuters can achieve. Engrossed in her podcast episode, Amy begins to execute a standard maneuver, switching from the center lane to the left lane of a three-lane highway, when an unexpected movement is caught by the very edge of her peripheral vision. This is when the trouble begins.
The unexpected movement triggers the first phase of the acute stress response, the startle reflex. Her system is flooded with adrenaline, a stress hormone that supercharges the body for survival reactions like fighting or fleeing danger. This unconscious re1ex causes her to simultaneously turn her attention toward the threat while moving her body away from it. Her arms jerk the wheel sharply to the right in order to move herself and her car out of the path of the incoming object.
Now that Amy has turned to face the approaching object, she enters the second phase of the response, intuitive assessment. She effortlessly and instantly identifies the mystery object as a motorcycle recklessly speeding in the left lane. Intuitively, she assesses the trajectory of the motorcycle compared to the trajectory of her own vehicle and, without the need for any actual math, she correctly calculates that she is no longer in danger of colliding with the driver. However, she is so focused on avoiding the cyclist that she doesn’t realize her reflexive motion, fueled by adrenaline, was an overcorrection, sending her car veering into the right lane. BAM!
Amy’s front bumper clips the side of a minivan. Her vehicle bounces back, thrown into the center lane. This is the moment when Amy officially enters a full fight-or-flight response, the third stage of the acute stress response. This stage is fueled by even more adrenaline along with a healthy dose of cortisol, another important stress hormone that increases focus, drives immediate action, and prioritizes fast, intuitive decision-making over logic and reason. She wrestles with the wheel to keep from rebounding into the motorcycle on her left. Supercharged by adrenaline, her foot slams down hard on the brake. She hears the squeal of tires from multiple vehicles and sees cars swerving all around as they try to avoid rear-ending her. In her panic, Amy is frozen in her seat. Only her eyes move, darting between her mirrors and windows, as the traffic slows to a crawl around her. Miraculously, no additional crashes occur.
A robotic voice fills the car, “Vehicle crash detected. Connecting to OnStar Emergency.” Amy remembers that OnStar crash support service came included with her car purchase and is equal parts embarrassed and relieved when a few seconds later a “real human” comes on the line. “This is Randall with OnStar. Is anyone injured?” This rational question kicks Amy’s brain out of the panic mode of fight or flight and into the fourth stage, reasoned reaction. She reports that she is uninjured, but she is unsure about the people in the other vehicle. Centered by Randall’s clear, step-by-step directions, Amy follows his instructions to pull her badly damaged car to the side of the road and confer with the other driver. Luckily, no one in the van is injured either. Still, Randall offers to send a police officer to the scene to create an accident report for the insurance company and Amy agrees.
By the time Amy parks her car on the shoulder, her heart rate and breathing have almost returned to normal. Amy has now entered the recovery period, the fifth and final stage. Since her response to the accident involved very little physical exertion, Amy still has plenty of leftover adrenaline in her system, causing shaking hands and jitteriness. While she waits for the police to arrive, she channels her restless energy into using her phone to do all kinds of things: taking down the other driver’s contact information, texting her boss to tell her she’ll be late for work, and taking pictures of the damage to her own car and the minivan. She even uses her insurance app to file a claim and order a tow truck for her car, and then orders an Uber for herself to the nearest car rental agency. Although it will be another hour or two before the effects of the adrenaline and cortisol fully wear off, Amy, her car, and all the other people and vehicles involved in the incident will make a full recovery from this stressful morning.
Amy’s acute stress response both helped and hurt her during this encounter. First, it helped her reflexively avoid a collision with the motorcycle, but this caused her to overcorrect and hit the minivan. Next, it helped her wrestle the car back under control, though in bringing it to a sudden stop, she nearly caused a pileup. And finally, it took her back to rational thinking in the end, allowing her to
execute a flurry of activity in the aftermath of the event.
At each step of the response, her ancient instincts had to work with multiple types of modern interfaces: digital, physical, and voice con- trolled. Some of those interactions were more successful than others. Different parts of the stress response require different approaches from designs. Understanding those various needs is critical to creating designs that can properly protect and empower a user in a moment of crisis.
Startle Reflex Considerations
When you are designing for a startle response, it’s helpful to remember that a startle response is a powerful force of nature, allowing humans to respond to danger with lightning-fast reactions. You can attempt to harness it through your designs, but this requires your interface to be in just the right place at just the right time. In Amy’s story, her hands were on the steering wheel at the moment she was startled, so she was able to use the wheel to jerk out of the path of the motorcycle. This reaction is exactly why drivers are instructed to keep their hands on the wheel at all times while controlling a vehicle. Physical interfaces like steering wheels, buttons, and knobs tend to be better at capturing these speedy reactions than touchscreens, but there are design lessons that can be borrowed from these analog controls to maximize the responsiveness of all kinds of digital interfaces including touchscreens, which we’ll explore more in Chapter 2, “The Startle Reflex.”
It’s also important for designers to keep in mind that, more often than not, startle re1exes are just a nuisance. Either they are false alarms, or they cause someone to overreact, like Amy careening into the right lane after jerking away from the motorcycle. Designers should always take steps to minimize false startle moves, or, if prevention is impossible, put systems in place to protect users from themselves in these uncontrolled, reactionary moments. We’ll dig into specific techniques for accomplishing these goals in Chapter 2.
Intuitive Assessment Considerations
When Amy turned to assess the threat level of the speeding motorcycle, this assessment, like all intuitive knowledge, happened instantaneously in her subconscious through a process of pattern matching. Even though she had never seen that particular vehicle before, she was able to match it to the category of objects she had learned was listed as “motorcycles.” Similarly, she was able to predict the motorcycle’s trajectory intuitively, based on how she had seen similar vehicles move in the past.
It’s important to note that nearly all of the driving maneuvers Amy executed throughout this story were powered by her intuition. She never once stopped to calculate how many degrees to turn her wheel to avoid a collision. All of her interactions came from an intuitive understanding of the car’s interface, which she had developed through years of repeated use.
Note: A Dangerous Learning Curve
It takes time and practice to develop reliable intuition for tasks as complex as driving. This is why the first 18 months of driving are so dangerous for new drivers, with car accidents topping the list of causes of death among American teenagers.
Designing for intuition can be a mixed bag. On the one hand, a truly intuitive interface can make technology feel almost like an extension of the user, allowing the person to focus all of their conscious efforts on the problem they are trying to solve. However, there are times when creating interfaces that rely too heavily on intuitive decision-making, unrestrained by fact checking or logic, can lead users to make hasty decisions that are overly influenced by harmful biases and stereotypes. When you are designing for intuition, it is critical to understand the types of environments where this subconscious ability to match patterns and automate decision-making is helpful, and the kinds of situations where users need to have their bias checked by the systems they use. We’ll explore different techniques for maximizing the benefits of intuition and minimizing the drawbacks in Chapter 3, “Intuitive Assessment.”
Fight, Flight, or Freeze Considerations
When a fight-or-flight response is triggered, the user’s rational mind is no longer in charge. No matter what their original objective was, now survival is the only goal. Often, users forget about technical solutions altogether in this state, falling back on more primal methods of dealing with danger. But, occasionally, users are forced through circumstances to interface with technology while in the grips of panic.
During Amy’s accident, her use of technology (AKA the car interface) during her fight-or-flight response was highly inconsistent. On the one hand, the fight-or-flight response enhanced her physical strength in a way that helped her get the car steering back under control after hitting the minivan. But the instinct to slam hard on her brakes, a form of the freeze response, actually increased her risk of a second collision with the cars behind her. This kind of unpredictable performance is very common when someone is panicking.
The best thing that technology can do when someone is in fight-or- flight mode is to protect them from harm and get them back to a rational state of mind as quickly as possible. For someone triggered to flee a situation, always allow them to exit or quit if they wish. Additionally, consider ways to provide clear, unobstructed paths to help, preferably human help. For someone in fight mode, look for ways to deescalate the situation. For those who are frozen in fright, give clear, specific direction to help them snap out of their indecision. (For example, the type of direction the OnStar operator Randall provided for Amy.) All of these techniques and more will be explored in Chapter 4, “Fight, Flight, or Freeze.”
Reasoned Reaction Considerations
More often than not, to survive and thrive in the modern world requires more logic than instincts. Well-designed systems and services can help users act rationally in a stressful situation by taking complex, multifaceted procedures and breaking them down into step-by-step processes. As illustrated in Amy’s story, companies like OnStar will design talk paths for their operators that allow them to triage the information-gathering process quickly and efficiently in an emergency. The goal is to ask about injuries first, and then address safety concerns like getting out of traffic, before moving on to more mundane issues like accident reports and insurance claims. Having these conversation flows written out and streamlined by the design team ahead of time allows the operator to stay calm and focus on the needs of the person in the crash, while executing each step correctly and in the right order of priority.
Experiences that are well crafted for reasoned response help users focus on the most relevant information for the task at hand and make well-informed choices at every step in the process. Techniques for designs that support rational decision-making under stress are explored thoroughly in Chapter 5, “Reasoned Reaction.”
Follow the Signal
Your senses capture raw data from the outside world just the same way a microphone, video camera, thermometer, accelerometer, or other electronic sensor might. And just like a machine, incoming data from each of your senses are turned into electric signals that travel through the brain for processing. When an acute stress response is triggered by something the senses can see, hear, or feel, that signal takes a very specific path through your brain and body, which is mapped in Figure 1.1.
Figure 1.1
A map of the signals related to the acute stress response as they travel through the brain and body.
SENSORY THALAMUS: The sensory thalamus is essentially the switchboard for the senses. Normally, it sorts incoming information from the senses and passes it on to the appropriate parts of the brain for decoding. But when it detects something sudden and unexpected, it sends out a special super-fast signal to the amygdala.
AMYGDALA: The amygdala is the central coordinator within the sympathetic system, the body system that controls the fear response. It’s located in the mid-brain sitting just above the spinal cord. When the amygdala receives the emergency signal from the sensory thalamus, it sends two signals, one to the hypothalamus and one to the hippocampus.
HYPOTHALAMUS: The hypothalamus is a small but mighty region at the base of the brain that controls a number of functions; the most critical to the stress response is the release of the hormone adrenaline that triggers the startle reflex. All of this happens within about 100 milliseconds (a 10th of a second) from when the motion was caught by the peripheral vision.
HIPPOCAMPUS: The hippocampus holds experiential memories, for example, memories that are gained through seeing and experiencing things, as opposed to facts or concepts learned in other ways. If the suspected threat matches a memory of something dangerous, then the amygdala will trigger a full fight-or-flight response by activating the HPA axis.
HPA AXIS: HPA stands for hypothalamus, pituitary gland, and adrenal gland, which, when triggered, flood the bloodstream with the stress hormones adrenaline and cortisol. When this happens, energy is redirected from nonessential systems like digestion, reproduction, and immunity to supercharge the circulatory and respiratory systems—the moment when the fight-or-flight reaction truly sets in.
PREFRONTAL CORTEX: Logic and reason come from the part of the brain at the very front of the forehead called the prefrontal cortex. Although its response time is a fraction of a second slower than the hippocampus, it has the ability to overrule the more primal survival responses if it thinks the body is taking the wrong actions.
PARASYMPATHETIC SYSTEM: When the crisis is over, the parasympathetic system sends a signal down the spinal cord, telling each body system to return to normal. The circulatory, respiratory, and immune systems bring the heart rate and breathing to normal. The release of acetylcholine restarts any temporarily suppressed processes in the digestive, reproductive, and other nonessential systems.
Recovery Period Considerations
Users often turn to technology for help in the aftermath of a stressful event. In Amy’s story, as soon as she resolved the immediate threat, she was on her phone engaged in a flurry of activity.
While the physical aftereffects of adrenaline, like shaking hands, may be of some concern to interface designers, of much more relevance are the lingering mental effects of cortisol during this period. Cortisol drives action. In low-to-moderate levels, it is extremely helpful in terms of focus and motivation. During an acute stress response, however, cortisol floods the brain, intensifying focus to the point of tunnel vision and compelling a person to address the immediate threat to the exclusion of all other goals. High levels of cortisol can cause poor decision-making, reduce creative problem solving, and increase aggression in users. And while the effects of an adrenaline rush rarely last for more than an hour, cortisol can take several hours to be filtered out of the bloodstream.
These negative mental effects have major implications for all kinds of designs used in the aftermath of a stressful event. Luckily, designers can help shorten this recovery period by designing aesthetics that calm the person and lead to empowering actions. In Chapter 6, “Recovery,” we’ll examine all the techniques that designers can leverage to help users weather the recovery period.
Finding the Peak Stress Points for Your Users
As a designer, being aware of the potential moments of crisis or stress for your users is critical to designing a supportive experience. Here are some questions to ask yourself or discuss with your col- leagues to help you find the moments of peak stress within the user experiences you design:
- What are the circumstances where you must deliver bad news to your user? (Example: Service outage or telling a customer a bill is past due.)
- What are the points where the user may discover bad news that your company/digital product is not necessarily aware of yet? (Example: Their account was hacked.)
- What are some upsetting things that might have happened to someone that would cause them to turn to your company/digital product for help? (Example: Customer in car crash and uses insurance app to order a tow truck.)
- If a bully or domestic abuser were trying to use your app/product to harass or harm one of your users, how might they use your digital product to do so? (Example: Abuser cancels power to victim’s apartment through a previously shared utility account.)
For additional insights, it can be helpful to map these stressful moments. These stress points can be added to a high-level strategy document like a customer journey map that illustrates all of the stages a customer goes through when interacting with your company. Or, if your product is already designed, you can map them directly to your interface designs. Are there certain screens that handle a lot of stressful moments? Or if you are designing voice-based interfaces or diagraming service experiences, are there places within your flow of user interactions that are hot spots for stress? These can be the first places you start to apply the lessons in this book.
It can also be helpful to interview users who have gone through the types of stressful situations you identify and ask them about the type of help they wish they had had in their moment of crisis. Performing a contextual inquiry, which means observing someone as they actually experience and deal with the stressful experience, would generate even richer and more accurate insights—however, many crises are rare, dangerous, emotionally traumatic, or unpredictable, making direct observation impossible or inadvisable. Additionally, it’s important to be especially mindful of research ethics when interviewing users about past upsetting experiences. Make sure that you are giving them proper compensation, providing a safe environment, and not asking them to relive their trauma.
Critical Information: The Human Stress Response
An acute stress response is triggered when a human is faced with an immediate threat. When designers understand the specific neurological and physiological effects of the stress response, they are better able to create experiences that support users in critical moments. See the phases of the stress response in Figure 1.2.
Figure 1.2
The five stages of the stress response elicit different emotions, actions, and neurological activity.
