But memory isn’t perfect.
Memory involves three major processes: encoding, storage, and retrieval.
Human memory involves the ability to both preserve and recover information.
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However, this is not a flawless process.
Sometimes people forget or misremember things.
Other times, information is not properly encoded in memory in the first place.
Memory problems are often relatively minor annoyances, like forgetting birthdays.
However, they can also be a sign of serious conditions such asAlzheimer’s diseaseand other kinds ofdementia.
These conditions affect quality of life and ability to function.
This article discusses how memories are formed and why they are sometimes forgotten.
Once the information has been successfully encoded, it must be stored in memory for later use.
Researchers have long believed that memories form due to changes in brainneurons(nerve cells).
Strengthening these connections helps commit information to memory.
This is why reviewing and rehearsing information improves the ability to remember it.
Practice strengthens the connections between the synapses that store that memory.
The memory retrieval process allows us to bring stored memories into conscious awareness.
How Long Do Memories Last?
Some memories are very brief, just seconds long.
Such memories allow people to take in sensory information about the world.
Short-term memories are a bit longer and last about 20 to 30 seconds.
These memories mostly consist of the information people are currently focusing on and thinking about.
Some memories are capable of enduring much longerlasting days, weeks, months, or even decades.
Most of these long-term memories lie outside of immediate awareness but can be drawn intoconsciousnesswhen needed.
Why Do We Remember Painful Memories?
Have you ever noticed that many times,painful memoriestend to hang on for long periods of time?
Of course, this process is not always perfect.
This is an example of a perplexing memory retrieval issue known aslethologicaor the tip-of-the-tongue phenomenon.
But to get to be retrievable, memories have to be organized in some way.
One way of thinking about memory organization is the semantic web link model.
Certain stimuli can also sometimes act as powerful triggers that draw memories into conscious awareness.Scentis one example.
Sensory Memory
Sensory memoryis the earliest stage of memory.
People only pay attention to certain aspects of this sensory memory.
Attending to sensory memory allows some of this information to pass into the next stage: short-term memory.
In Freudian psychology, this memory would be referred to as theconscious mind.
Paying attention to sensory memories generates information in short-term memory.
Most information stored in active memory will be kept for approximately 20 to 30 seconds.
Some memory researchers now believe that the true capacity of short-term memory is probably closer to four.
Long-Term Memory
Long-term memoryrefers to the continuing storage of information.
InFreudian psychology, long-term memory would be called the preconscious andunconscious.
This information is largely outside our awareness but can be called into working memory for use when needed.
Some memories are fairly easy to recall, while others are much more difficult to access.
Sensory memory is very brief, short-term memory is slightly longer, and long-term memory can last a lifetime.
Why We Forget Some Memories
Forgetting is a surprisingly common event.
Just consider how easy it is to forget someones name or overlook an important appointment.
Why do people so often forget information they have learned in the past?
Information is often quickly forgotten, particularly if people do not actively review and rehearse the information.
Some memories compete with one another, making it difficult to remember certain information.
In other instances, people activelytry to forget thingsthat they simply dont want to remember.
By the time people reach their 80s, it is common to experience some decline in cognitive function.
But some types of memory even increase with age.
Takeaways
Human memory is a complex process that researchers are still trying to better understand.
Our memories make us who we are, yet the process is not perfect.
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