What is Echoic Memory & How Does Echoic Memory Work?

Also known as auditory sensory memory, echoic memory is a type of human memory that stores auditory information or sound in the brain. Echoic memory is a subdivision of human memory. There are three major types of human memories,⁽¹⁾ including:

• Long term memory that is responsible for retaining facts, events, and skills. Long term memory keeps the information from a couple of hours to even decades.
• Short term memory is responsible for storing information that has been received recently. Short term memory can retain data for a couple of seconds to one minute.

Sensory memory, also known as sensory register, is responsible for holding data from your senses. Sensory memory can further be divided into three types. These are:

• Echoic memory, which stores auditory information from the sense of hearing
• Iconic memory, or visual sensory memory, that stores visual information
• Haptic memory that holds data from the sense of touch

The primary function of echoic memory is to store the audio information as your brain works at processing the sound. Echoic memory also saves bits of auditory information, which gives meaning to an overall sound.⁽²⁾

When we hear a sound, the auditory nerve sends this sound to the brain. This happens in the form of electrical signals that get transmitted to the brain. At this point, the brain perceives this sound to be raw and in the form of unprocessed audio information.

Echoic memory comes into play when this unprocessed, raw data is received and held by the brain. This information is stored in the brain’s primary auditory cortex (PAC). PAC is found in both the left and right hemispheres of the brain.

The data that is held in the primary auditory cortex that is opposite to the ear that heard the sound first. For example, if you hear a noise with your left ear, then the right primary auditory cortex will save the memory. However, if you listened to the sound with both ears, then both the right and the left PAC will retain the sound.

After a couple of seconds, though, this echoic memory will be moved into the short-term memory.⁽³⁾ Short term memory is the place where your brain processes the data and then proceeds to give meaning to the sound that was heard.⁽⁴⁾

There is nothing that we need to do when it comes to echoic memory. The entire process is automatic, meaning that the sound will enter your echoic memory even when you are not making any effort to listen.

In fact, the brain is continuously forming many echoic memories throughout the day. Let us look at some examples.

One of the most common examples of where echoic memory comes into play is when you are talking to another person. When somebody is talking, your echoic memory automatically retains each individual word, even syllable. Your brain will then recognize the words by connecting each individual syllable to the previous one.

Each spoken word gets stored into the echoic memory, allowing the brain to comprehend a fully formed sentence.

When you are busy, and someone is talking to you, sometimes you are unable to fully hear what they are saying. When you ask them to repeat what they were saying, then it is bound to sound familiar because your echoic memory has already heard them the first time, even though you might not have registered it at that time.

When you are listening to music, your brain is making use of your echoic memory. The brain will briefly recall a previous note of the music being played and then connect it to the next note. As a result of this, your brain is able to recognize the notes as a song.

Echoic memory is only able to store information for about 2 to 4 seconds. According to the Handbook of Neurologic Music Therapy, echoic memory is concise, and this brief duration means that your brain is able to generate many echoic memories during the day.⁽⁵⁾

Every human being is born with echoic memory. However, there are many factors that can affect how good or bad the echoic memory of a person is. Some of these factors may include:

• Age
• Substance abuse
• Hearing loss or hearing impairment
• Psychiatric disorders such as schizophrenia⁽⁶⁾
• Neurological disorders such as Alzheimer’s disease⁽⁷⁾
• Language disorders

The effectiveness of an echoic memory also depends on certain characteristics of a sound, including:

• Volume
• Duration
• Intensity
• Frequency
• Language (whether it is with or without a spoken word)

Also known as visual sensory memory, iconic memory is what stores visual information. Just like echoic memory, iconic memory is also a type of sensory memory. However, iconic memory is much shorter than echoic memory, and it lasts for even less than half a second.

This is because the brain processes images and sounds in different ways. This is because of the fact that most of the visual information we see does not immediately disappear, and we are able to view the same image repeatedly. Furthermore, when we look at an image, the brain is able to process all the visual images together at the same time.

Echoic memory lasts longer than iconic memory, and this is useful to us because sound waves are time-sensitive. It’s not possible to keep on reviewing the same sound until unless the actual sound gets repeated.

Also, the sound is processed by the brain as individual bits of information rather than as a whole. Each individual bit of noise gives meaning to the previous sound bit, which together then gives sense to the overall sound. Due to this, the brain requires more time to store auditory information rather than visual information.

It is normal to forget some things from time to time. It happens with all of us. It is also reasonable to experience some level of memory loss as we get older. However, if you are facing some serious memory challenges, then you should consider seeing a doctor.

Seek medical help if you are having memory problems such as:

• Repeatedly asking questions
• Getting lost in familiar places
• Forgetting how to say some common words
• Depending on what your specific challenges are, your doctor may refer you further to a specialist such as a neurologist or a psychologist.

Whenever you hear a sound, the audio information goes into your echoic memory, which lasts for just 2 to 4 seconds before the brain is able to process the sound you have heard. So even though the echoic memory lasts for a very short time, it still helps store the information in your brain even after the sound has come to an end.

So even though we all have echoic memory, certain factors, like age and neurological disorders, can have an effect on how well you are able to recall sounds. It is also normal for your memory to start declining as you age.

However, if you are experiencing some sort of memory issues, then it is advisable to seek medical help at the earliest.

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