Echoic Memory: Definition and Function in Psychology
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. It is a subcategory of human memory, which can be divided into three major categories:
- Long-term memory retains events, facts, and skills. It can last for hours to decades.
- Short-term memory stores information you recently received. It lasts for a few seconds to 1 minute.
- Sensory memory, also called the sensory register, holds information from the senses.
Sensory memory can be further broken down into three types: Iconic memory, or visual sensory memory, handles visual information. Haptic memory retains information from your sense of touch. Echoic memory holds audio information from your sense of hearing.
Echoic memory stores auditory information or sounds. It’s a part of sensory memory and holds these sounds for a brief period, typically around 3 to 4 seconds, even after the original sound has ceased.
The purpose of echoic memory is to store audio information as the brain processes the sound. It also holds bits of audio information, which gives meaning to the overall sound.
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.
Following the initial registration, the sounds resonate and are replayed in the mind (Radvansky, 2005). Listening to a song: When we listen to music, our brains briefly recall each note and connect it to the ensuing note. Conversing with another person: When we hear spoken language, our echoic memories retain every individual syllable.
Repeated speech: When what someone says to us is not clear, we may request the repetition of what was mentioned. However, the duration of the echo that exists following the presentation of the hearing signal seems to be a point of debate.
In 1974, Graham Hitch and Alan Baddeley proposed a human memory model with a phonological loop that attends in two ways to auditory stimuli (Baddeley & Hitch, 1974; Baddeley, Eysenck & Anderson, 2009). This system supposedly comprises an initial 200 to 400-ms input phase followed by an information transferring phase. The other section comprises a sub-vocal process of rehearsal that refreshes the original memory trace by utilizing the individual’s inner voice.
George Sperling’s research on iconic memory in the 1960s subsequently inspired other researchers to test the same phenomenon utilizing similar means in the auditory domain (Darwin, Turvey & Crowder, 1972). Likewise, the subjects in the echoic memory experiments had to repeat sequences of syllables, words, or tones that they heard.
ABRM involves presenting a brief target stimulus to the subjects and then, following a brief interval, presenting the mask [a second stimulus] (Bjork & Bjork, 1996). Performance seems to improve as the interstimulus interval is raised to 250ms.
Echoic memory involves several distinct brain regions on account of its various processes. The rehearsal system and the phonological store seem to be left-hemisphere systems with increased brain activity (Kwon, Reiss & Menon, 2002). As mismatch negativity research suggests, such cognitive and developmental growth is likely to occur until adulthood before experiencing a decline in old age (Glass, Sachse & Suchodoletz, 2008).
Everyday Examples of Echoic Memory
Here are a few everyday examples:
- Talking to 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. 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. If they repeat what they said, it will sound familiar because your echoic memory heard them the first time.
This brief duration means your brain can make many echoic memories throughout the day.
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
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.
Sensory Memory Diagram
When to Seek Medical Help
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.
When you hear a sound, the audio information enters your echoic memory. It lasts for 2 to 4 seconds before your brain can process the sound. While echoic memory is very short, it helps keep information in your brain even after the sound has ended.
Though we all have echoic memory, factors like age and neurological disorders can affect how well you recall sounds. It’s also normal for memory to decline with age.