Absolute threshold is a very specific psychological and sensory term.
We define it as the smallest intensity of a stimulus that has to be present for the stimulus to be detected. The most common example of this involves sensitivity to heat.
Think of an electric burner on a stove. You place your hand on the burner and then turn it on the lowest setting. At first, you won’t feel anything because it takes time for the coils to heat up. Eventually, it will get warm enough for you to detect heat; there is some temperature that is just hot enough for you to notice it. Not hot enough to get burned, but just enough for you to become aware of the change in temperature.
In this case, your absolute threshold is the point at which it is just hot enough for you to detect the presence of the heat. Now for someone else, the absolute threshold would be higher or lower, sooner or later. In psychology, such a variation in perception or feeling is referred to as a threshold.
“Languages are so much easier for Tom; he just has a facility with language.”
“You know those pictures you can’t see unless you stare at them all cross-eyed. Mary can see those almost immediately.”
“Cindy can taste when a dish needs salt or seasoning; my taste buds aren’t that sensitive.”
“Little Billy can shoot those alien invaders before I even see them on the screen.”
Can you see how all of those statements reflect a difference in thresholds for one person as opposed another?
We are all unique. With that uniqueness comes very different sensitivities to all kinds of stimulus and input from the world around us. How quickly we pick up on sights, sounds, smells, etc. is a measure of our absolute threshold.
We all have different levels of response to heat, light, sound, color and dozens of other sensory inputs. Your particular response or perception of a stimulus is your threshold.
It is possible to measure when you become aware of something and often your awareness precedes your conscious recognition of the stimulus. You know when someone says: “The noise from those fluorescent lights is driving me crazy.”
You hadn’t even noticed the annoying buzz, but now that someone has mentioned it, you can’t stop hearing it. Did you not hear the noise before? Or has your absolute threshold for the noise been reset by them mentioning the sound?
There is another interesting concept in psychology called signal detection theory, which says that our ability to observe is not an absolute quantity but rather depends on situational and motivational factors. Simple example, I tell you that your appointment is over when the music begins to play. What I don’t tell you is that the music will start very low and slowly increase in volume. Because you were told about the music, you will hear it sooner, at a lower level, than someone who was not warned about the upcoming sound.
Here is the point. Absolute threshold can be reset to receive more information (“to hear the music sooner”) simply by paying attention. Signal detection is enhanced by paying attention to more information and the ability to remember the information and access it later.
Notice that nowhere have I mentioned remembering the information or storing the memory. In fact, studies have shown that with absolutely no attempt to increase memory or use any memory tricks whatsoever, an individual will recall more information simply by paying closer attention to events as they unfold. The additional information makes you more sensitive to more subtle clues you would have missed previously.
By resetting your thresholds higher, you remember more of what you see and hear even with no conscious effort on your part to save those memories. It is a proven function of threshold behavior that as you make more refined observations, you simply retain more information. The simple truth is that paying attention to details makes those details easier to detect.
Applications of absolute threshold are all around us. Hearing a baby’s cry, sensing traffic around us, awareness of change in temperature. Any input to your senses, whether seeing, hearing, tasting, smelling or tactile can be sharpened when we first become aware of our absolute threshold and then by paying attention that threshold.
Voices are my favorite example. We all have been in a situation with a partner where we didn’t pick up on the tone of their voice that said:
“I’m angry,” or “I need help,” or even “I need you to listen.”
When that happens, ask yourself, how long did it take me to recognize the tone? Now simply notice that sooner would have been better for you both. The next time this happens, your absolute threshold will have been reset, and you will pick up on the nuance in your partner’s voice sooner.