Do You Get Used to Everything?

A dot can fade without moving

Fix your gaze on a small point and a faint shape off to the side may disappear from awareness. This is Troxler fading. The shape remains on the screen; its visibility changes while you look elsewhere.

In a 2006 experiment, eight people watched a peripheral target while an eye tracker recorded their movements and they reported when it faded or returned. Tiny involuntary eye movements called microsaccades became less frequent before fading and more frequent before renewed visibility. That relationship helps explain why steady fixation can produce fading, even though our eyes are never completely still. Martinez-Conde et al., 2006

Sensory adaptation is a change in responsiveness during sustained stimulation. Habituation is a learned reduction in a response to repetition, such as a shrinking startle. Researchers distinguish it from sensory adaptation and from a muscle becoming tired. A response that recovers after a rest, or remains strong to a different stimulus, gives them clues about which process they are studying. Rankin et al., 2009

A response can shrink or grow

A sea slug supplied an unusually clear view of habituation. In Aplysia, a touch can trigger a defensive gill-withdrawal reflex. Castellucci and Kandel isolated nerve tissue and repeatedly stimulated sensory neurons while recording the response in motor neurons. The signal weakened. Their analysis traced the change to less chemical transmitter being released by the sensory cell, while the receiving cell's sensitivity remained unchanged. Castellucci and Kandel, 1974

Sensitization is an increased response, and it can coexist with habituation. In some pain conditions, increased responsiveness in pathways carrying pain signals contributes to pain from ordinarily harmless touch. Clifford Woolf's review calls this central sensitization. It contributes to some forms of chronic pain, with different degrees and durations. Woolf, 2011

Tolerance has another definition: the same dose of a drug produces less of a particular effect. Richard Solomon's opponent-process theory offered a model in which a pleasant response evokes an opposing reaction that strengthens with repetition. The stronger opposition reduces pleasure during exposure and leaves a worse state afterward. That pattern can help describe aspects of drug tolerance and withdrawal. Solomon, 1980

Addiction also involves processes that this picture leaves out. In Berridge and Robinson's incentive-sensitization account, cues associated with a drug can acquire an increased power to provoke wanting, even as the pleasure from taking it declines. Wanting and liking needn't move together. The account concerns addiction, rather than a general mechanism for enjoyable habits. Berridge and Robinson, 2016

The lottery story left things out

The famous 1978 lottery study interviewed 22 winners, 29 people paralyzed in accidents, and 22 controls. It didn't follow them from before the event to after it. Winners weren't significantly happier than controls at that one interview; the injured group was significantly less happy. The often repeated story that both groups returned to the same baseline goes beyond the experiment. Brickman et al., 1978

The fading impact of changed circumstances is often called hedonic adaptation. Lucas and colleagues used 15 annual waves of a German household survey to follow changes within the same people. Their marriage analysis followed 1,761 people who married and stayed married: average life satisfaction rose around marriage and then moved back toward its earlier level. Individual changes varied substantially. Widowhood showed a more persistent average loss during follow-up. Neither finding gives a newly married or bereaved person a two-year deadline. Lucas et al., 2003

In a British panel, Oswald and Powdthavee found partial recovery in life satisfaction following the onset of work-limiting disability, while average satisfaction remained lower, especially with severe limitations. Their paper explicitly disagrees with earlier estimates of very little recovery. These are statistical averages, with no prediction for an individual's recovery. Oswald and Powdthavee, 2008

Lindqvist, Östling and Cesarini surveyed 3,362 Swedish lottery players 5 to 22 years after prizes were awarded. Comparing players whose prize amounts had been randomly determined, they found lasting gains in overall life satisfaction. Effects on reported happiness and mental health were smaller and weren't statistically significant. The follow-up was a single survey, not a record of each winner's mood over those years. Lindqvist, Östling and Cesarini, 2018

A prize may improve someone's judgment of their finances long after the initial excitement passes. A question about life as a whole and a question about feelings right now measure different things.

Stutzer and Frey's German panel analysis found that longer commutes were associated with lower life satisfaction, including in comparisons within the same people over time. It didn't establish that nobody adapts to commuting, or identify an income increase that would causally compensate a commuter. Stutzer and Frey, 2008

A route that takes an hour each way still consumes two hours after you learn every turn. Familiarity can change how the journey feels without returning the time. Before relying on future adaptation, it helps to ask which part of a problem would actually have to change.

A break can restore some enjoyment

Quoidbach and Dunn had 55 students taste chocolate at two sessions a week apart. Between sessions, one group abstained, another received a large supply, and a control group received no instruction about consumption. At the second tasting, the abstaining group reported more savoring and positive feeling than the other groups. Quoidbach and Dunn, 2013

That is a small experiment about one food over one week. It suggests a way to keep a favorite treat enjoyable; it doesn't establish a general reset for pleasure. Taking a break from chocolate is also quite different from depriving yourself of company, rest or security.

Another experiment changed attention rather than consumption. Koo and colleagues asked participants to write about how a positive event might never have happened. Thinking through the near-miss produced more positive feeling immediately afterward than simply describing the event's presence. In a relationship experiment, they selected people who were already relatively happy in relationships lasting at least five years. The result doesn't promise lasting affection or repair a troubled relationship. Koo et al., 2008

The exercise can be quite ordinary. How did you end up knowing a particular friend? Which chance meeting made that possible? Looking at the route by which something arrived may make it easier to notice. Imagining catastrophe isn't required.

These experiments concern noticing an existing pleasure. Accepting continuing harm is a different proposition.

Surprise affects a moment's happiness

In Rutledge and colleagues' gambling experiments, people repeatedly reported how happy they felt while receiving certain rewards and taking risks. A model using recent rewards, expectations and the difference between expected and actual outcomes predicted those ratings. Cumulative winnings alone didn't account for the fluctuations. A smartphone version tested the model in 18,420 players earning points. Rutledge et al., 2014

A welcome surprise can therefore matter even when it barely changes a total. But the model also gave positive expectations a role before the outcome arrived. Setting expectations low isn't a free way to increase happiness: you give up some anticipation along the way.

The measurements were brief ratings in a reward task. Extending them into "you feel the slope, not the height" skips the rest of a person's life. Improving circumstances can still leave someone in pain or short of money.

An alarm can become routine

A warning that has accompanied several uneventful days can start to seem less urgent. That reassurance may affect a decision even when the danger hasn't changed.

Practice can make more visible

Repetition can also improve recognition. Chase and Simon showed chess positions briefly to a master, a class A player and a beginner, then asked them to reconstruct the boards. The master's advantage was much greater for positions from real games than for randomly arranged pieces. Their explanation was learned groups of pieces, or chunks. The master had encountered arrangements that made the board easier to remember. Chase and Simon, 1973

This classic study had three participants. It illustrates memory supported by knowledge of chess, with no claim that the master possessed a generally superior memory.

Some practiced responses become less demanding of deliberate attention. In Shiffrin and Schneider's visual-search experiments, people learned to find target characters among distractors. With a consistent distinction between targets and distractors, detection became easier. When the roles were reversed, the old learning interfered: characters people had learned to ignore now needed a response. Repeating a task and practicing flexible responses aren't automatically the same thing. Shiffrin and Schneider, 1977

Making the familiar strange

William James described one benefit of habit in 1890: it "diminishes the conscious attention with which our acts are performed." A familiar action can leave us freer to think about something else. That was his account of everyday conduct, long before the visual-search experiments. James, 1890

The critic Viktor Shklovsky was interested in what habitual recognition leaves out. In his 1917 essay on art, he argued that an unfamiliar description can slow perception and let us experience something we ordinarily pass over. His phrase was "to make the stone stony." This is a claim about what art can do, not a laboratory demonstration of dishabituation. Shklovsky, 1917

A painting of a familiar street might draw a viewer's attention to window shapes they ordinarily pass by. That is the attention Shklovsky describes, without requiring a return to a first impression.

We can sometimes change where we look, how we practice, or how often we take a pleasure for granted. What that changes, and how long the change lasts, remains much harder to predict.

Studies and primary texts

Links beside the claims identify the evidence used. The list distinguishes experiments, observational panels, theories and literary interpretation. The four charts are conceptual illustrations, not plots of the studies' data.