It’s 4 a.m.,and the big test is in eight hours,
followed by a piano recital.
You’ve been studying and playing for days,
but you still don’t feel ready for either.
So,what can you do?
Well,you can drink another cup of coffee
and spend the next few hours cramming and practicing,
but believe it or not,
you might be better off closing the books,
putting away the music, and going to sleep.
Sleep occupies nearlya third of our lives,
but many of us give surprisingly little attention and care to it.
This neglect is often the resultof a major misunderstanding.
Sleep isn’t lost time,
or just a way to rest when all our important work is done.
Instead,it’s a critical function,
during which your body balancesand regulates its vital systems,
呼吸系统 血液循环系统 免疫系统 与身体的成长都会受到影响
affecting respiration and regulating everything from circulation to growth and immune response.
听起来很棒 但你可以在考试之后再担心这些 不是吗？
That’s great, but you can worry about all those things after this test, right?
Well,not so fast.
It turns out that sleepis also crucial for your brain,
with a fifth of your body’scirculatory blood
being channeled to it as you drift off.
And what goes onin your brain while you sleep
is an intensely active periodof restructuring
that’s crucial for how our memory works.
At first glance,
our ability to remember things doesn’t seem very impressive at all.
19th century psychologistHerman Ebbinghaus
demonstrated that we normally forget40% of new material
within the first twenty minutes,
a phenomenon knownas the forgetting curve.
But this loss can be preventedthrough memory consolidation,
the process by which information is moved
from our fleeting short-term memory to our more durable long-term memory.
This consolidation occurs with the help
of a major part of the brain,
known as the hippocampus.
Its role in long-term memory formation
was demonstrated in the 1950sby Brenda Milner
in her research witha patient known as H.M.
After having his hippocampus removed,
H.M.’s ability to form new short-term memorieswas damaged,
but he was able to learn physical tasksthrough repetition.
Due to the removal of his hippocampus,
H.M.’s ability to form long-term memories was also damaged.
What this case revealed,among other things,
was that the hippocampuswas specifically involved
in the consolidation oflong-term declarative memory,
such as the facts and concepts you need to remember for that test,
rather than procedural memory,
such as the finger movements you need to master for that recital.
Milner’s findings, along with workby Eric Kandel in the 90’s,
have given us our current model of how this consolidation process works.
Sensory data is initially transcribed
and temporarily recorded in the neuronsas short-term memory.
From there, it travels to the hippocampus,
which strengthens and enhancesthe neurons in that cortical area.
Thanks to the phenomenonof neuroplasticity,
new synaptic buds are formed,allowing new connections between neurons,
and strengthening the neural network where the information will be returned as long-term memory.
So why do we remembersome things and not others?
Well,there are a few ways to
influence the extent and effectiveness of memory retention.
比如 那些在情感或压力强烈时 所形成的记忆
For example, memories that are formedin times of heightened feeling, or even stress,
will be better recorded due to the hippocampus’ link with emotion.
But one of the major factors contributingto memory consolidation is,
you guessed it, a good night’s sleep.
Sleep is composed of four stages,
the deepest of which are knownas slow-wave sleep
and rapid eye movement.
EEG machines monitoringpeople during these stages
点脉冲在脑干 海马体 丘脑
have shown electrical impulses moving between the brainstem, hippocampus,
thalamus, and cortex,
which serve as relay stationsof memory formation.
And the different stages of sleep have been shown to help consolidate
different types of memories.
During the non-REM slow-wave sleep,
declarative memory is encodedinto a temporary store
in the anterior part of the hippocampus.
Through a continuing dialoguebetween the cortex and hippocampus,
it is then repeatedly reactivated,
driving its gradual redistributionto long-term storage in the cortex.
REM sleep, on the other hand,
with its similarity to waking brain activity,
is associated with the consolidationof procedural memory.
So based on the studies,
going to sleep three hours after memorizing your formulas
and one hour after practicing your scales would be the most ideal.
So hopefully you can see nowthat skimping on sleep
not only harms your long-term health,
but actually makes it less likely
that you’ll retain all that knowledge and practice from the previous night,
all of which just goes to affirmthe wisdom of the phrase,”Sleep on it.”
When you think aboutall the internal restructuring
and forming of new connectionsthat occurs while you slumber,
you could even say that proper sleep
will have you waking up every morning
with a new and improved brain,
ready to face the challenges ahead.