In this lesson, you will learn about sensory memory, how it relates to other types of memory, and two specific types of sensory memory called echoic and iconic memory.
According to the Atkins-Shiffrin theory, memory involves three distinct but related processes: sensory memory, short-term memory and long-term memory. Together, these processes provide the avenue for environmental information to be received by the senses and either put to use, stored for later use or ignored altogether.Most people associate memory processes exclusively with the brain, and for the most part, that is accurate. What is responsible for getting the information from the senses to the brain? That’s where sensory memory becomes so important.Our senses are directly linked to our central nervous system, which is comprised of our spinal cord and brain.
The process of getting information from our senses to our brain happens very quickly. In fact, it happens so quickly that we are not always consciously aware of everything that is being picked up by our senses.Sensory memory allows environmental information to be retained, sometimes for as little as a fraction of a second, as it makes its way into our consciousness. Our sensory systems are constantly receiving and processing an incredible amount of information at any given moment. As we go through our day, it is virtually impossible to consciously recognize all of this information.
Stop and think for a moment about what you are doing right now. Your eyes are taking in the visual information of the light in the room, the letters and words that comprise this lesson and all the things that are going on in your peripheral vision simultaneously. Even if you’re in a relatively quiet room, if you stop and really listen you will hear that there are quite a few noises and sounds occurring all around you.Sensory memory absorbs a tremendous amount of environmental information.
It also provides our brains with a lot of details in a short amount of time. Using the examples mentioned above, you are not only seeing and recognizing objects or hearing and recognizing sounds around you. Your eyes are seeing colors, texture, size and shape. Your ears are hearing tone, pitch and loudness.
A whole host of detailed information must be taken in through our senses very rapidly.It’s pretty amazing how quick and efficient our sensory systems are when you think about it. Sensory memory allows our brains to make quick reactions and judgments without having to wait on the information to be processed by conscious thoughts. Quite often the information taken in through the senses does end up being consciously processed and used in short-term memory or stored in long-term memory, but thanks to sensory memory, our brains can rapidly sense and perceive a host of environmental information while our brains decide what is useful and what is not.
Types and Examples
Sensory memory plays an important role in receiving and processing environmental influences from all five senses. However, visual and auditory information tend to receive the most attention. In fact, researchers have uncovered certain unique characteristics of sensory memory within these two sensory systems that distinguishes them from one another and the other sensory systems.
- Echoic memory is a specific type of sensory memory involved in processing auditory information.
- Iconic memory is a type of sensory memory that is unique to our visual system.
Echoic memories can be retained for several seconds before they are either lost or put to use by our brains. Think about the last time you had a conversation with someone. Thanks to echoic memory, you would likely have little difficulty repeating back what he or she said word-for-word immediately after the first statement without really thinking about it. The words that were just spoken were retained long enough by the echoic memory process to allow you to recognize the sounds without much conscious effort. You can remember the term ‘echoic memory’ by thinking of an echo.
While echoic memory can last for several seconds, iconic memory lasts for only a fraction of a second. Iconic memories are the visual images that you see in your mind’s eye. As you look at an object, taking in all of its attributes, iconic memory is responsible for creating a visual representation of that object in your brain.Even though they don’t last long, iconic memories are what allow you to perceive an object in our environment and decide to attend to it or ignore it. For example, imagine you are driving down a busy highway and all of a sudden a car in the lane next to you swerves into your lane.
Your eyes take that information, where within a fraction of a second your iconic memory creates a visual image in your mind of what is happening. It lasts just long enough to allow your brain to understand what is happening and react accordingly. Not all examples are as extreme as swerving cars.
In fact, iconic memory is playing a critical role in your ability to read this lesson.
Sensory memory is a critical component of our overall memory process. It allows us to sense a lot of information while our brains decide what is important and what is not. Two types of sensory memory are echoic memory, which is responsible for auditory information; and iconic memory, which is responsible for helping us to hang on to visual images.
After you finish this lesson, your aim should be to:
- Recognize the three processes included in the Atkins-Shiffrin theory
- Explain what sensory memory is
- Describe echoic memory and iconic memory