Iconic Memory And How It Works
Iconic memory is just one component of your overall memory function, but it plays an important role in your ability to interpret the world around you. Typically lasting only milliseconds, iconic memory helps you process what you see and use that information to form new memories. Below, we’re discussing iconic memory, its functions, and how it works.
What Is Iconic Memory?
Sensory memory is ultra-short-term memory that lasts only milliseconds for most people. Because snap impressions of scenes are used to round out perceptions and reach conclusions regarding visual cues, iconic memory can be vital to our ability to interpret our surroundings and determine when things are askew.
Some people confuse iconic memory with photographic memory. While there is little evidence that photographic memory is a real phenomenon, iconic memory is a proven component of memory function, with a wide body of research confirming its existence. Photographic memory is the ability to see something and remember it from a brief image alone. Iconic memory is simply your brain's way of processing visual information via the initial display of any given visual stimuli.
suggest that iconic memory does not last long. You can experience iconic memory through a simple exercise. Close your eyes for a few seconds, then open them for one or two seconds (just long enough to focus on an object), and then close them again. For a very brief time, you should continue to see the image in your mind's eye. That is iconic memory at work, keeping the image intact for a brief time after the stimulus is no longer present.
Persistence And Iconic Memory
Persistence refers to the continuation of a visual impression even after the stimuli have passed. It is thought to be the main mechanism underlying the function of iconic memory. Three types of persistence have been implicated in visual stimuli and iconic memory tasks: neural persistence, visible persistence, and informational persistence.
Neural persistence occurs when your neural activity continues after the stimuli are gone. Visible persistence is when you continue to see the image after it is gone, such as with a bright flash of light. Informational persistence is when information about the visual stimuli is still available to you for some time after the stimuli are gone.
Informational persistence is a primary aspect of iconic memory. Informational persistence has distinct properties from visible or neural persistence, as both visible and neural persistence rely heavily upon the visual cortex. Informational persistence does not rely as heavily on the visual cortex, as it converts the visual display to abstract ideas and information instead of a simple image.
Researchers once believed that these three forms of visual persistence rely upon one another and are the source of visual information relayed after stimuli are no longer available. However, new research has found that this is not the case. According to recent studies, two phenomena consistently occur with visual stimuli: the inverse duration effect, in which the longer a stimulus lasts, the briefer its persistence after stimulus offset; and the inverse intensity effect, which describes the duration of persistence based on the strength of the stimulus.
Temporal Characteristics Of Iconic Memory
Iconic memory decays rapidly after the visual stimulus is no longer present. Iconic memory is regarded by most to allow for the perceptual integration of two or more images, even if separated by a brief period. Many studies have been conducted to determine the duration of iconic memory, usually after the stimulus has been removed (called stimulus offset).
One study hypothesized that iconic memory has a set temporal property starting from the onset of the visual stimulus, regardless of how long the stimulus is displayed. This would account for the inverse action of the iconic memory lasting for a briefer period with a longer duration. The previous studies measured the duration of iconic memory from stimulus offset, but this measures it from stimulus onset.
The new study's results seem conclusive, showing that regardless of how long visual stimulus is displayed, iconic memory has a fairly set duration. Most often, the duration of iconic memory is less than one second. Only when iconic memory is put into context in the brain and relegated to short-term memory does the information persist beyond the single second associated with visual short-term memory.
Iconic Memory’s Journey Through The Brain
The primary part of the brain that is involved in iconic memory is the occipital lobe, which is home to the primary visual cortex. The occipital lobe and its primary visual cortex are responsible for processing and controlling visual information. The visual stimulus travels from the visual system of the eyes to the occipital lobe, where it is stored for mere milliseconds, before being discarded or transferred to the temporal lobe. The hippocampus within the temporal lobe is primarily responsible for converting that memory from short-term to long-term memory.
The path of visual memory is one that is traveled extremely quickly. Iconic memory, visual working memory, and short-term memory have limited capacities and brief temporal characteristics, some of them housed within the primary visual cortex. Only by moving information all the way through the process to long-term memory can visual stimuli be remembered for more than a few minutes; iconic memory requires attention and focus to transfer information to longer-term memory banks.
The first thing that must happen, of course, is for visual stimuli to be presented. The visual system and the occipital lobe process visual stimulus. Automatic recognition occurs, and it is then placed into iconic memory. This happens very quickly—said to occur in as little as one second in iconic memory and less than one minute in visual working memory.
Once the stimulus has initially been presented, iconic memory begins. The automatic recognition of the visual stimulus display is processed by the occipital lobe and transferred to iconic memory, where it remains for only milliseconds before being transferred to visual working memory or being discarded.
From iconic memory, the information moves to visual working memory. This is like an extremely short-term memory in vision and visual stimuli. Visual working memory can last for several seconds. For information to move to visual working memory, the subject must have focused attention on the visual display or set of information.
The short-term memory lasts only a few minutes and has limited capacity. With focused attention and interrelated memories and thought, visual working memory can be transferred to short-term memory. There, the information remains for several minutes before being discarded or being shuffled along to long-term memory. If information from iconic memory is to last beyond a few minutes, it needs to be stored in long-term memory.
Storage Of Iconic Memory
Many studies have been done to determine the rate of transfer of information from iconic memory to long-term memory. Most studies have found that it takes significant attention for our brains to store iconic memory. Without focused attention, the iconic memory fades rapidly and is not put into a context that commits it to more long-term memory.
The amount of information that can be moved from iconic memory to long-term storage is limited by the capacity of the short-term memory and the availability of iconic memory. One study showed that iconic memory, with attention, could be transferred to visual working memory, which lasts several seconds. This memory in turn only lasts seconds, less than a full minute, without being transferred again to long-term memory.
Online Therapy For Memory-Related Emotional Challenges
If you struggle to remember things you have seen, you might be experiencing early memory loss in visual areas. Memory impairment has been connected to mental health conditions such as depression, anxiety, and bipolar disorder. So, managing the emotional effects of memory loss can be important.
Studies show that online therapy can help individuals reduce the negative emotional and cognitive effects of memory impairment. In one study, participants displayed improvements in memory and mood following an online therapy program. These results can be added to those of an increasingly large number of studies that point to the efficacy of online therapy for a range of mental health and cognitive challenges.
If you’re struggling to process emotions related to memory loss or similar challenges, online therapy can help. For those experiencing memory loss, it may be difficult to keep track of appointments. With online therapy through BetterHelp, you can be frequently reminded of upcoming sessions and schedule appointments at times that are most compatible with your cognitive function. Your therapist can also connect you with useful resources, such as articles about memory or at-home memory-enhancing exercises.
Takeaway
Frequently Asked Questions (FAQs):
What Is Iconic Memory In Psychology?
Iconic memory is a term coined by George Sperling. Sperling identified the process of an entire visual movement from a single, immediate impression via iconic memory, to visual working memory, to short-term memory. These classic initial experiments identified iconic memory as the first threshold in the integration of visual information.
Iconic memory, then, is a gateway, of sorts, for the processes involved in storing short-term memory. A visual stimulus offsets the brain, which triggers iconic memory. Iconic memory holds onto the image for one second or less, before sending the image to the brain, which quickly identifies whether the image is important or unimportant.
Without iconic memory taking in information and quickly discarding it, the human brain would be continually overwhelmed by visual stimuli. Iconic memory is a sorting machine, essentially, filtering through all the images taken in daily.
What Is Iconic Echoic Memory?
Iconic memory and echoic memory are two different types of memory intake. Iconic memory is involved in eye movements, and entire visual intake, while echoic memory focuses on auditory intake and sorts information based upon auditory receptors. Like iconic memory, echoic memory is short, and does not necessarily route all incoming information immediately to short-term or long-term memory for extended storage.
How Long Does Iconic Memory Last?
Iconic memory is incredibly brief, lasting a second or less. This is, in part, why change blindness is observed in iconic memory; iconic memory is not used to store a great deal of visual information over a long period of time, so iconic memory is prone to change blindness, or the inability to identify small changes made to a scene.
Iconic memory is often linked to visual working memory, which is not as prone to change blindness, and is the part of memory in change detection that can last several seconds—long enough to display the ability to detect change.
Why Is Iconic Memory Important?
Although iconic memory is known for change blindness and is used in a pre-attentive state, it is a vital part of the primary visual cortex and its functions. Through inadvertent or unintentional eye movements, the human mind takes in a veritable cascade of visual information, which must be processed via the primary visual cortex and either discarded or rerouted to the next channels of visual memory. From this primary visual intake center (iconic memory), memories are either deemed no longer necessary and discarded, or shuffled along to the next destination: visual working memory.
A type of memory that struggles with change detection tasks might not seem to be terribly important, but it plays an essential role in neurological function. Being constantly overwhelmed by visual stimuli could mean a loss of general brain function; if a large portion of the brain was constantly focused on filtering and sorting through visual input, other functions would have to be put on the back burner. Iconic memory takes over these functions and performs the task of sorting through and removing unnecessary information.
How Can I Improve My Iconic Memory?
Iconic memory is not necessarily an impulse or “muscle” you can “exercise.” Instead, iconic memory is the involuntary initial step in visual processing. Although memory can be strengthened with regular use and intentional practice, iconic memory is not actually a storage site, or a type of memory bank; instead, it is the gatekeeper in visual processing.
Images are taken in via iconic memory, routed to the visual cortex, and deemed either unnecessary or worthy of storage. Iconic memory can be used briefly to recall a small amount of information or, when viewed in conjunction with other sensory stimuli, recall a larger amount of information through a partial report paradigm. Partial report allows people to deliver more information but is still subject to the rapid-fire nature of iconic memory.
Although you cannot quite improve your iconic memory in the same way you might work to improve your short term or long-term memory, you can regularly practice partial report procedure to encourage your ability to deliver a partial report.
To successfully enlist the partial report paradigm, view a given visual stimulus while engaging another sense, such as listening to a specific song or sound, or chewing on a cracker. When trying to recall the image you are in search of, enlist that same sensory stimulus, and you should be able to deliver a partial report, or a greater portion of the visual stimulus taken in via your iconic memory.
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