Sensory memory is one of several memory types that make up your ability to process and recall what you see. Sensory memory is a brief precursor to short-term memory that allows you to process and recall the sensations you take in.

Keep reading to find out about sensory memory, including how doctors identified this memory type in the first place.

Sensory memory is a very short-term, but large capacity memory source. One way to think of this memory type is like the start of your memory. It’s when you take in everything around you before transmitting a portion of what you see to short-term memory.

A common analogy for sensory memory is that the memories are your “raw data” that your brain then processes to make sense and order.

Doctors estimate that sensory memory lasts a few hundred milliseconds, according to a 2016 article.

During this time, the brain is receiving signals from multiple sensory signals, which include what you see, smell, and hear. However, even with all the stimulation, your brain is able to attend to and target most of the aspects you want to focus on.

Unfortunately, sensory memory starts to decline as a person ages. Doctors think the time the brain takes to process sensory information starts to slow down, according to an article in the journal Frontiers in Aging Neuroscience. As a result, the brain takes in or computes less sensory information.

The knowledge of how sensory memory affects us is important in the study of memory and aging. Because sensory memory is a first input that helps to build a person’s short- and long-term memories, knowing that it slows down with aging can help to understand why and where memory starts to decline.

Sight, smell, touch, taste, and sound — these are the five senses that help you process the world around you. In terms of sensory memory, researchers have mostly studied three aspects:

Visual memory

Doctors call visual sensory memory iconic memory. Researchers have conducted lots of studies about this type and found the eyes aren’t able to transmit some objects in motion to memory. This means for visual sensory memory to work well, you and the object you’re observing must be still.

So what if the object (or you) isn’t still? In this case, your brain won’t transmit the signals clearly. Think of it like taking a picture that ends up blurry. Your brain can’t transmit the images well enough to fully commit them to memory.

An example is an experiment that helped researchers first identify visual memory. A researcher would show an image, quickly followed by a flash of light. Most participants couldn’t identify or recall the image due to the flash. Researchers concluded the brain didn’t have time to enter and interpret the sensory image.

If your sensory memory can’t capture these memories well, why are you still able to remember things when you’re moving? The good news is you have other methods of creating memories other than visual sensory memory. It’s just one of the tools at your disposal.

Auditory memory

Auditory sensory memory is when a person uses the things they hear to create memories. Doctors also call auditory sensory memory echoic memory. An example could be listening to and recalling a list of items. Auditory and visual sensory memory have some interesting differences.

For auditory sensory memory, when a person hears a list, they tend to remember the first and last words spoken the most, according to an article in the journal Frontiers in Aging Neuroscience.

However, this isn’t the same for visual memories. If a person sees a list of items, they’re more likely to remember the first items and not always the last ones.

Another example of the power of auditory memory is an older study from 1986 published in the Journal of Experimental Psychology: Learning, Memory, and Cognition. Participants were read a list but asked not to remember the last item on the list.

The researchers first read the list in the same voice tone the entire time. Then, they read the list again but made their voices sound different for the last item that a person wasn’t supposed to remember.

The researchers found people were more easily able to remember the list when the last word sounded different. They concluded the brain is better able to process memories when there are differences in sensation.

However, when the researchers read the list more slowly with a different tone, people weren’t able to recall the list as effectively. To the researchers, this illustrated how quickly sensory memory works and also how fast it can go away.

Touch memory

Doctors also call touch memory haptic memory. The field of haptic memory research is newer but promising. One example of how haptic memory may work is a study published in the journal Psychological Science.

Researchers in the study asked participants to hold an object in their hands for 10 seconds. They’d then hand the person two similar objects, such as two pens, and ask the person to identify the pen they previously held.

If they asked this question almost immediately after a person had held the first object, 94 percent of people could identify the first object they held.

One of the most common examples of sensory memory is the use of a sparkler, which is a handheld firework.

When you hold the firework in your hand and move it in different patterns, your eyes perceive a line or trail of light. The sparkler isn’t truly creating a line, your eyes just cannot process the information fast enough when it’s in motion, so what you see is a trail.

Even though sensory memory is usually very short, there are instances when you can recall the sensory memory. An example could be when you read a word with your eyes, yet recall how a person sounds when saying it.

Sensory memory is vital to helping you process and compute the world around you. Once you see, hear, smell, touch, or taste sensory information, your brain may either process or discard the sensations.

Knowing how each aspect of sensory memory affects you may help you understand how you’re able to recall some sensory information, yet not other aspects of memory.