Sensory Adaptation

Last week I touched on the concept of priming in which exposure to a stimulus heightens the response to that stimulus .  More exposure increases the response to that stimulus so, as in the example I gave before, when you are shopping for a specific model of car you are probably going to notice that car more often.  This effect is so profound that it can begin to feel that there are actually more Nissan Altimas on the road than before (or more people talking about priming, or more websites about psychology, or whatever else you may stumble upon).

This can be useful for us because when something novel is introduced to us, it’s probably a good idea to keep an eye on it until we know what it is.  If I’m a caveman just hanging out in my cave and I see a new animal around my sweet cave dwelling, it’s probably not a bad idea to be ever-aware of its presence until I figure out whether or not it’s a threat to me.  So what happens when I determine it’s not a threat?  What happens when the novel and the insignificant just becomes insignificant?  Dedicating energy (physical or mental) to insignificant stimuli is a waste of our resources, so how do we handle that?

Sensory Adaptation

Sensory Adaptation and Priming

Initially we are more aware of a new stimuli but as time passes we become less aware.

In my post about The Psychology of Stimulation I hinted at the effect of sensory adaptation in my example of the large furnaces that were in my childhood schools.  These absurdly loud things buzz and hum so loudly that when they turned off the teacher inevitably spent a few seconds yelling at us before adjusting to the change in noise level.  That’s not the interesting part though.  The interesting thing about this example is that in spite of their loudness, they were inevitably tuned out while they were on. They were tuned out so effectively that their silence was temporarily more intruding than their loudness.  What’s going on here?

The answer is sensory adaptation.   In the most simple terms, as our brain determines that a stimulus is unimportant, or even distracting, it (more accurately, central nervous system) simply begins to ignore it.  We will cover the biology of this process in a later post but the chart above provides a nice visual.

Real World Example

Sensory adaptation happens every day and all around.  It’s why your friends house stinks yet they don’t know what you’re talking about. It’s why you don’t smell the perfume you put on this morning by the time you get to class.  It’s why the buzzing of the florescent light above you doesn’t seem to buzz, until I just pointed it out to you. This is a very cool video that does a great job explaining sensory adaptation and shows you a really neat trick in which you will see sensory adaptation at work firsthand.  Here’s a hint: Do this right, and you’ll see the network of capillaries that feed blood to your eye. Were you able to get it to work? Let us know!

  • Kathryn

    Lacunae exposed. Well done! Yes, the wiggle-thing works.