How Sensory Adaptation Works

Imagine that you just walked into your favorite Italian restaurant. The delicious smell of garlic and tomatoes is almost overwhelming when you first walk through the door. You sit down to wait for a table, and after a few minutes, the scents dissipate until you barely notice them. This is an example of sensory adaptation.

Read on to learn more about sensory adaptation and how it works. We also explore examples of sensory adaptation and how it differs from habituation.

What Is Sensory Adaptation?

Sensory adaptation is a reduction in sensitivity to a stimulus after constant exposure to it. While sensory adaptation reduces our awareness of a stimulus, it helps free up our attention and resources to attend to other stimuli in our environment.

All five senses can experience sensory adaptation. Our senses are constantly adjusting to what's around us, as well as to us individually and what we are experiencing, such as aging or disease. It is important to note that sensory adaptation does not occur with pain perception.

Causes of Sensory Adaptation

Sensory adaptation, also known as neural adaptation, occurs due to changes in the neural receptor cells that receive and process sensory information. Perception is how we recognize and interpret what is coming in through our senses. Research suggests that sensory adaptation occurs within the multiple stages of perceptual processing.

This adaptive change can occur slowly or quickly. Fast adaptation happens very quickly, in the span of milliseconds. Slow sensory adaptation can occur over minutes, hours, or even days. Some evidence suggests that repeated exposure to stimuli may allow people to "learn" how to adapt faster to the change.

Sensory adaptation serves an important function by helping people tune out distractions and focus on the most relevant or important stimuli around them. Imagine what it would be like if you didn't experience sensory adaptation. You might find yourself overwhelmed by the pungent smell of onions coming from the kitchen or the blare of the television in the living room.

Examples of Sensory Adaptation

Here are some more examples of the types of sensory adaptation that happen in real life and affect different senses.

• Scent: Smokers are not bothered by the smell of tobacco smoke the way nonsmokers are, because smokers are accustomed to the odor. Their sensory receptors respond less to the stimuli (the smell of smoke) because they experience it often.
• Sight: When you go into a dark room or outside at night, your eyes eventually adjust to the darkness because your pupils enlarge to let in more light. Likewise, when you are in bright light, your eyes adjust to the narrowing of your pupils.
• Touch: When you jump into a cold swimming pool or first get into a hot tub, the water may feel unpleasantly cold or much too hot, but eventually, your body adjusts to the temperature, and it feels only mildly cool or perfectly pleasant.
• Taste: With the first bite of a very flavorful dish, you'll notice the strong saltiness, sourness, or sweetness of the food. But after a few mouthfuls, your taste buds will adapt, and the flavor will not be as pronounced.
• Hearing: A classic example is city dwellers who can tune out traffic and other urban sounds. Their sleep isn't disturbed by the sounds outside their windows, because they have adapted to the noise. Imagine living by train tracks!

Sensory Adaptation vs. Habituation

Sensory adaptation and habituation both involve reduced attention to a stimulus, but the two concepts have important differences. 

Sensory adaptation is an automatic, involuntary process that involves becoming less sensitive to sensory stimulation at the cellular level.

Habituation is a phenomenon involving a decrease in the perceptual experience when exposed to the same sensory stimuli over time. In other words, perception is the psychological result of the cellular process that occurs when our senses are stimulated. As our senses adapt to familiar stimuli, our perception and experience will change, or habituate.

While habituation may occur without much thought, we are often aware that something we once enjoyed no longer has the same effect. Or, vice versa, something that once bothered us, is long forgotten. Some examples are below:

• Ticking clock: When a room is quiet, you can hear the ticking of a clock from 30 feet away. Once your senses have adapted, or your attention shifts elsewhere, you no longer perceive the ticking sound.
• Favorite meal: If you order the same dish every time you eat at a restaurant, you might find yourself enjoying it less after you become accustomed to it. You might even start to notice things you don't like about the meal.
• Drug use: When you use drugs repeatedly, your body no longer responds as it once did, and you no longer experience the same degree of pleasure.
• Relationships: We can also habituate to relationships as time goes on. As we become more familiar with someone and know what to expect, our senses are no longer on high alert. As we become less stimulated, we may perceive the relationship differently and become complacent.
  

A Word From Verywell

If you've heard the term "nose blind," you've heard of sensory adaption; it's the same thing. (But it's different from anosmia, or the inability to smell.) You also might notice that when you're away from a smell or a sound for a while, such as when you go on vacation and then return to your home, you notice it again. It will probably not take much time for you to adapt to the sensory inputs of your environment and go "blind" to them once again.