Long-term memory is the relatively permanent memory storage system that holds information indefinitely. In it we store last year’s football scores, the image of an elephant, and how to ride a bicycle. We also appear to be storing information that we can’t consciously retrieve, but which still affects our behavior.
Long-term memory involves three stages, encoding, storage and retrieval (getting information in, keeping it there and then getting it back out), and appears to contain several different kinds: episodic, semantic, declarative and procedural.
Stages of long-term memory
Encoding is the label given to the way in which objects and events in the world come to be represented in memory. Our normal perception of objects and events requires considerable encoding. However, the application of further encoding processes can produce memory representations of objects and events that differ considerably from those arising solely from perceptual processes.
A memory store is where non-active memory representations are held. For example, imagine your favorite item of clothing. When not in use, the memory representation upon which this image depends will be held in a memory store.
Retrieval is the label given to the way in which information held in memory is made available for use. Retrieval involves finding, activating and sometimes further processing pertinent memory representations.
Types of long-term memory
Long-term memory appears to contain several different kinds of memories.
For example, episodic memories record life experiences. Your memory of your first day of school, the events at last week’s company meeting, or the birth of your first child are all examples of episodic memories. Retrieval of these memories usually involves associations with particular times or places.
Semantic memories store information about the world independent of time, place, or other contexts. They store facts, rules, and concepts. Semantic memories include all organized knowledge we have about words, their meanings, and how we manipulate them. We all have semantic memories about the word “elephant” although we might not recall where or how we acquired them.
Procedural memories are memories for performing particular types of actions. While semantic memory is knowing “that,” procedural knowledge is knowing “how.” Here are some sentences that demonstrate procedural memory:
• I remember/know how to pick up a glass of water.
• I remember/know how to write my name.
• I remember/know how to tie my shoe.
The steps in various procedures are apparently stored in a series of steps, or stimulus-response pairings. When we retrieve information from procedural memory, we retrieve one step, which triggers the next, which triggers the next, etc.
These various parts of long-term memory do not operate in isolation from one another. While it is not clear how they work together, it is clear that they are related and overlap.
Sleep improves long-term memory
There are a number of ways to improve and keep your child’s long-term memory sharp. One simple way is to make sure that he or she gets enough sleep. Children who do not get enough sleep have been shown to perform more poorly on memory and attention tests.
Sleep helps the brain commit new information to memory through a process called memory consolidation. In studies, people who’d slept after learning a task did better on tests later.
Masaki Nishida and Matthew Walker, of the Sleep and Neuroimaging Laboratory at Harvard Medical School’s Department of Psychiatry, enlisted 26 healthy participants for the study. One morning, the participants were trained to perform a simple motor task with the left hand; the task involved learning a sequence of 5 key presses. The participants were split into two groups; one group had an afternoon nap lasting between 60-90 minutes after learning the task, while the other remained awake.
The ability of all the participants to perform the task as quickly and as accurately as possible was then tested. In those who had taken a siesta, there was a significant improvement in performance of the task. By contrast, no significant improvement in task performance was observed in the participants who had remained awake.
Memory is not a gift. It’s a skill
Advertisers tout supplements. Organic growers push blueberries. But, because memory is a skill and not a gift, for true memory improvement you must train your brain.
The belief that memory can be trained is not new. The Greeks, and later the Romans, developed some of the most prodigious memories the civilized world has ever seen. Memory was ranked as one of the most important disciplines of oratory, a flourishing art at the time. They lived in an age with no paper, so people couldn’t readily refer to notes. Speeches were committed to memory; lawyers depended on their memory in court; and poets, whose role in society was paramount, regularly drew on their enormous powers of recall to recite long passages of verse.
Today, external aids supplant memory. We rely on calculators, cell phones, smart phones, computers and the Internet to assist memory recall, with the result that people get very little training in developing and improving their memory skills. In children, the result can be underachievement in school.
According to researchers from Durham University, who surveyed over three thousand children, children who underachieve at school may just have poor working memory rather than low intelligence.
Working memory is the ability to hold information in your head and manipulate it mentally. You use this mental workspace when adding up two numbers spoken to you by someone else without being able to use pen and paper or a calculator, or when remembering a new telephone number, PIN number, web address or vehicle registration number.
Important information is gradually transferred from working memory to long-term memory. The more the information is repeated or used, the more likely it is to eventually end up in long-term memory. Unlike working memory, which is limited and decay rapidly, long-term memory can store unlimited amounts of information indefinitely.
The Durham researchers found that ten percent of school children across all age ranges suffer from poor working memory seriously affecting their learning. Without appropriate intervention, poor working memory in children can affect long-term academic success into adulthood and prevent children from achieving their potential.
At Edublox we follow a holistic approach and improve not only long-term memory, but also iconic memory, short-term memory, working memory, visual memory, auditory memory, and sequential memory.