Understanding Echoic Memory: Definition, Function, and Examples
Most people are familiar with the concept of "memory" as the ability to recall events that happened previously. But what is echoic memory? Echoic memory is the brief sensory memory of audible sounds. It’s a type of sensory memory that registers and temporarily holds auditory information (sounds) until it is processed and comprehended (Carlson, 2010). This automatic but temporary auditory memory response is a component of sensory memory.
Following the initial registration, the sounds resonate and are replayed in the mind (Radvansky, 2005). Echoic memory has a role in our perception of auditory stimuli in our world. Memories start by receiving sensations from our five senses. Specifically, echoic memory is sensory memory associated with auditory information received from the environment. The term echoic stems from the word echo, which is in reference to the brief echo, or the reverberation of sound that is transmitted neurologically via this type of sensory memory. An echoic memory example occurs with conversation.
Echoic memory continually processes sound from our environment. Echoic memory is constantly “on,” meaning that your brain automatically picks up sounds and stores them, albeit briefly. Echoic memory allows the brain to retain spoken syllables in order for the brain to process them into intelligible speech.
How Echoic Memory Works
When you hear something, your auditory nerve sends the sound to your brain. It does this by transmitting electrical signals. At this point, the sound is “raw” and unprocessed audio information. Echoic memory occurs when this information is received and held by the brain. Specifically, it’s stored in the primary auditory cortex (PAC), which is found in both hemispheres of the brain. The information is held in the PAC opposite of the ear that heard the sound. For instance, if you hear a sound in your right ear, the left PAC will hold the memory. But if you hear a sound through both ears, both the left and right PAC will retain the information.
After a few seconds, the echoic memory moves into your short-term memory. This is where your brain processes the information and gives meaning to the sound. The process of echoic memory is automatic. This means audio information enters your echoic memory even if you don’t purposely try to listen. In fact, your mind is constantly forming echoic memories.
Duration of Echoic Memory
Echoic memory is a type of sensory memory that temporarily stores auditory information or sounds for a brief period, typically for up to 3-4 seconds. Echoic memory lasts three to four seconds before the information disappears. Subjects weren’t able to distinguish segments that were longer than a few seconds, but were able to recognize segments that were less than two seconds long. If someone wishes to remember the brief burst of information in their echoic memory, they must consciously transfer the auditory information into their short-term memory.
Examples of Echoic Memory in Daily Life
Here are a few everyday examples of echoic memory:
- Conversing with another person: Spoken language is a common example. When someone talks, your echoic memory retains each individual syllable. Your brain recognizes words by connecting each syllable to the previous one. Each word is also stored in echoic memory, which allows your brain to understand a full sentence.
- Listening to music: Your brain uses echoic memory when you listen to music. It briefly recalls the previous note and connects it to the next one. Echoic memory allows the brain to interpret individual notes into a recognizable song. As a result, your brain recognizes the notes as a song.
- Asking someone to repeat themselves: When someone talks to you while you’re busy, you might not fully hear what they say. When someone is distracted and asks a friend, "What did you say?" Echoic memory is the reason that they immediately recognize the words even when they weren't actively listening to the conversation. The person's echoic memory retained the words even though it was not done consciously. If they repeat what they said, it will sound familiar because your echoic memory heard them the first time.
Factors Affecting Echoic Memory
All humans have echoic memory. However, various factors can influence how well someone has this type of memory.
Possible factors include:
- Age
- Neurological disorders, such as Alzheimer’s disease
- Psychiatric disorders, such as schizophrenia
- Substance use
- Hearing loss or impairment
- Language disorders
It also depends on the characteristics of a sound, including:
- Duration
- Frequency
- Intensity
- Volume
- Language (with spoken word)
Echoic Memory vs. Iconic Memory
Your echoic memory stores audio information (sound). It’s a type of sensory memory along with iconic (visual) and haptic (touch-based). Of the five, our senses of vision and hearing are more prominent in our perception of our surroundings. Visual sensations are stored very briefly (around 200 milliseconds) in iconic memory.
Iconic memory, or visual sensory memory, holds visual information. It’s a type of sensory memory, just like echoic memory. But iconic memory is much shorter. It lasts for less than half a second. That’s because images and sounds are processed in different ways. Since most visual information doesn’t immediately disappear, you can repeatedly view an image. Plus, when you look at something, you can process all the visual images together.
Echoic memory is longer, which is useful because sound waves are time sensitive. They can’t be reviewed unless the actual sound is repeated. Also, sound is processed by individual bits of information. Each bit gives meaning to the previous bit, which then gives meaning to the sound. As a result, the brain needs more time to store audio information.
| Feature | Echoic Memory | Iconic Memory |
|---|---|---|
| Sensory Input | Auditory (Sound) | Visual (Sight) |
| Duration | 3-4 seconds | Less than 0.5 seconds |
| Processing | Sequential, bit-by-bit | Simultaneous, all at once |
| Retention Usefulness | Requires longer duration due to time-sensitive sound waves | Shorter duration sufficient as visual information is readily available |
The Importance of Seeking Medical Help for Memory Problems
We all forget things sometimes. It’s also normal to experience some memory loss as we get older. But if you’re having serious memory issues, it’s important to see a doctor.
Seek medical help if you have memory problems, such as:
- Getting lost in familiar places
- Forgetting how to say common words
- Repeatedly asking questions
- Taking longer to do familiar activities
- Forgetting names of friends and family
Depending on your specific issues, a doctor might refer you to a specialist, like a psychologist or neurologist.