Sleeping - Homework.docx

Sleep -presentationToday i will present you my study about something that most of us loves, and that is sleep. Contrary to the common belief sleep is not some break time when your brain and your body goes dormant. It is an entirely different state of conciousness and only in the past few decades have we began to elucidade why we sleep, in the first place, and what happens when we are doing it to what are the concesquences of not doing it. Even if you seem dead to the world in that time your “perceptual window” remains slightly open. The common definition of sleep is: Sleep is a periodic, natural, reversible and near total loss of conciousness. Although we spend about a third of our lives sleeping and we know it is essential to our health and survival, there still aren’t enough scientific consensess for why we do it. The most common assumptions are that we do it for simple recuperation, allowing our cells and neurons to rest and repair themselves, for growth because that is when our pituitary glands secrete hormones and that is why babies sleep all the time, plus sleep has all kinds of benefits for mental function, like improving memory, giving our brains time to process the events of the day and boosting our creativity. Even if we do not understand totally this phenomenon, technology has given us great insight into how we sleep, and for that we can thank Armond Aserinsky, a little boy from Chicago. One night after being tucked into his bed, Eugene Aserinsky, his father, decided to tape some electrods on his head instead of giving him good night kisses and telling him a goodnight story. So this is how the electrocencephalograph or EEG machine, created for measuring the brains electrical activity, was tested for the first time. After further investigations (not all of them on poor little Almond) mr. Aserinsky discovered that the brain doesn’t just “power down” like it was thought by the scientific world until then, instead the concept of sleeping stages was brought to the world and it was called REM which stands for RAPID EYE MOVEMENT. It is a period when the sleeping brain is buzzing with activity even though the body is not. Nowadays we know that we experience 4 disctinct stages of sleep, each definded by unique brainwave patterns. When the night comes and we go to sleep in our beds the pineal gland releases sleepy melatonin hormones so that our brain is relaxed but still awake and a level of activity is measured by the EEGs as alpha waves. You’re feeling asleep, your breath slows and suddenly you are asleep. This exact moment is clearly evident on a EEG reading as those alpha waves immediately transition to the irregular non-Rapid Eye Movement stage one (N-REM1) waves. During this time we can have the sensations of falling or running. As you relax more deeply you move into NREM-2 stage sleep as your brain starts exhibiting bursts of rapid brain wave activity called sleep spindles (ax). You are now definitely asleepd but you could still be easlily awakened. NREM-3 comes with slow rolling delta waves. It is know that you can have brief and fragmentary dreams in the first three stages of sleep, but eventually you’ll get to the most

important stage of sleep: FULL REM SLEEP, that famous stage of sleep when your eyeballs go nuts, you have vivid visual dreams and fuzzy ideas that you cant believe they came from your mind. Also your motor cortex is jumping all over the place but your brain is blocking those messages, leaving your muscles so relaxed that you are basically paralyzed, except for your eyes. Summing up the whole sleep cycle repeats itself every 90 minutes or so, transitioning back and forth between stages of sleep. Sleep is very imporant because it is linked to health, mental abillity, depression, weight gain, imune system supression. The most common sleep disorder is insomnia, which is persistent problems of falling or staying asleep. Another one but more rare (i think i might have it) is narcolepsy, a sleep disorder characterized by uncontrollable sleep attacks. Basically you are getting sleepy out of nowhere and you can fall asleep in just a few seconds. Sleeptalking and sleepwalking are pretty common things and they are not diseases but disorders which happen to to persons who are sleep deprived. And occur during the NREM 3 stage of sleep. But getting back to the REM sleep, oh, what dreams may come... tonight you will be in the REM stage of sleep and start dreaming. Suddenly you are naked, riding an unicorn trough the medschools corridors, trying to get as fast as you can to the english class, while also smoking a cigarette. Welcome to your dreams, those vivid emotional images racing through your brain when asleep. You can have very exotic dreams but mostly your dreams just unpacks and reshuffles of what you did, said and encountered during the day. So, why were you riding a unicorn in the medschool and smoking a cigarette on your way to the english class? Maybe because your little sister told you today 100 times that she wants an unicorn and you were late to the english class and also you wanted so bad to smoke a cigarette but you didn t had the time so you were running through the UMF. Why we’re you naked? Each one of us has its own fantasyes but lets not discuss that now. So, why are we sleeping though? Well, a lot of people tried to give and explenatino including the mighty Freud but not even his theory had suffiecent scientific basement. One of the most commonly accepted theories is that dreaming is healty for us because it promotes neural development and preserves neural pathways by providing brain stimulation.When our brains are stimulated they expand their connections more so babies for example spend much of their sleep time dreaming, perhaps in part to help their brain circuitry develop more quickly. Summarizing the informations, today you have learde that: \There are 4 stages of sleep: NREM1,2,3 and REM as well as some major theories and discoveries for the psychological purpose of dreaming, including information processing, physiological funcioin and neural activity models.