Remember that great summer vacation you took last year? When you
think back on it, you might see flashes of a day you spent swimming
or a night spent watching fireworks explode high in the sky. But
how do you store those images, so you can enjoy them later?
It's your memory - and it's part of your complex and
multitalented brain.
What Is Memory?
When an event happens, when you learn something, or when you
meet someone, your brain determines whether that information needs
to be saved. If your
brain
judges the information important, it places it in your memory
"files."
You probably know your brain has different parts. Some of them
are important for memory. The
hippocampus
(say: hih-puh-
kam
-pus) is one of the more important parts of the brain that
processes memories. Old information and new information, or
memories, are thought to be processed and stored away in different
areas of the
cerebral cortex
, or the "gray matter" of the brain - the largest,
outermost part of the brain.
What Can Go Wrong With Memory?
As wonderful as memory is, it isn't always perfect. It's
normal to occasionally forget the name of somebody you just met or
where you put your shoes. And of course, everyone has forgotten an
answer on a test. Darn! You knew that one, too!
It's also typical for people to forget more things as they
grow older. Your parents or grandparents might joke about having a
"senior moment." That's when they forget
something.
But some memory problems are serious, such as when a person has
Alzheimer's disease. Strokes, which also affect older people,
are another medical problem that can affect someone's memory. A
stroke is when blood doesn't get to all the parts of the brain,
either because there is a blockage in the pathway, or because a
blood vessel (which carries the blood) bursts.
Brain Injuries Affect Memory
And, at any age, an injury to the head and brain can cause
trouble with a person's memory. Some people who recover from
brain injuries need to learn old things all over again, like how to
talk or tie their shoes. That's why it's so important to
protect your head by wearing your seat belt in the car and wearing
a helmet when you skate, play football, ride your bike, skateboard,
or wear roller sneakers.
You may have heard about a memory problem called
amnesia
(say: am-
nee
-zhuh). This is when someone can't remember things that
happened a short time ago. This happens sometimes, but it's not
usually like you see on TV or in the movies. People rarely forget
their own names and they usually get better slowly, instead of all
at once because something dramatic happens - like getting kissed by
a dreamy prince or princess!
The most common cause of amnesia is a
traumatic brain injury
(TBI). A TBI is caused by a severe hit to the head. Traumatic brain
injuries can happen in a lot of ways and can be severe enough to
cause a coma (prolonged unconsciousness), or a person may just be
stunned without even being knocked out (like in some
concussions).
Car accidents, bike accidents, and falls can cause TBIs. If
you've ever seen someone take a hit to the head in a National
Football League game, you may have seen the player being questioned
on the sidelines. The doctor may ask the person some basic
questions - like what happened, where they are, and what team
they're playing. Not knowing the correct answers could be the
first sign of a brain inury.
Abusing alcohol or using illegal
drugs
is another way to injure the brain and cause memory problems.
Hallucinogens (like
LSD
or PCP) can alter certain chemicals in the brain that actually make
memories harder to recall.
Signs of a Memory Problem
A person might - or might not - be able to notice signs of his
or her own memory problem. If a person has suffered a brain injury,
doctors, nurses, and family members will be on the alert for signs
of trouble.
If someone has a memory problem, he or she will be unable to
remember important things for varying lengths of time. The more
severe the injury, the longer the memory loss is likely to last.
Some people forget just the moments right before and after the
injury, which is not unusual with a concussion. Sometimes, these
memories come back. More significant problems with memory may make
it hard to remember what happened days, weeks, months, or even
years ago, and it can be difficult to learn and remember new
things.
What Will the Doctor Do?
Any time a person has been hit in the head, it's important
to see a doctor. A doctor will test the person's ability to
recall events, names, or places by asking lots of questions. In the
case of a brain injury, a doctor may also want to take a picture of
the patient's brain and skull using something called a
CT scan
.
If the person has memory loss from a head injury, the doctor
will design a treatment plan to help the brain heal and, if
necessary, to help the person relearn things that have been
forgotten. If the memory problem is due to a person using drugs or
alcohol, the person needs to stop abusing these substances before
his or her memory will improve.
With strokes, memory can return but it depends on severity and
location of the stroke in the brain. With Alzheimer's, lost
memory cannot be restored, but scientists are working on medicines
they hope someday will prevent this kind of memory loss.
Most memory problems affect older people, so what can you do for
your memory if you're 8, not 88? In addition to remembering to
wear your helmet, use your brain! By doing challenging activities,
like reading and doing puzzles, you can exercise your mind so
you'll be remembering great memories for many years to
come!
Updated and reviewed by:
Larissa Hirsch, MD
Date reviewed: July 2007
Note: All information is for educational purposes only. For specific medical advice,
diagnoses, and treatment, consult your doctor.
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