TED: Why do we sleep? | Russell Foster

  • On average 36% of life is spent asleep 

  • The human attitude towards sleep changes over time

    • "Sleep is the golden chain that ties health and our bodies together." -- Thomas Dekker, Elizabethan dramatist 

      • writing in Shakespeare's time 

    • "Sleep is a criminal waste of time and a heritage from our cave days." -- Thomas Edison, inventor of the lightbulb, the opponent of the night [CM language]

      • beginning of the 20th century

  • NEUROSCIENCE 

    • Though we are unconscious to its activity, the brain remains highly active during sleep 

    • Scientists lack general consensus when answering why we sleep

      • Two (2) theories according to Russell Foster 

        • 1. Restoration: "Essentially, all the stuff we've burned up during the day, we restore, we replace, we rebuild during the night." 

          • A whole raft of genes have been shown to be turned on only during sleep, and those genes are associated with restoration and metabolic pathways 

        • 2. Brain Processing and Memory Restoration 

          • After you've tried to learn a task, if you are sleep-deprived, the ability to learn that task is "hugely attenuated." 

          • Our ability to come up with novel solutions to complex problems is hugely enhanced by a night of sleep 

    • Sleep enhances creativity 

    • Neural connections and synaptic connections that are important are linked and strengthened, while those that are less important tend to fade away 

  • SLEEP DEPRIVATION 

    • 1950s : 8 hrs average

    • Present day : 6.5 hrs average 

    • Teens need 9 hours for peak brain performance 

      • many get as little as 5 

  • JET LAG

    • As unpleasant as it is, there is evidence than a 16 hour long fast (no consumption) will reset your clock following jet lag. Difficult, yes, but this is an essential step to take. It is always essential to do all that we can to heal our bodies when they are hurt, hurting, broken or breaking. It is our top priority to heal ourselves as soon as possible. This is peak performance. 

    • "When you're tired and you lack sleep, you have poor memory, you have poor creativity, you have increased impulsiveness, and you have overall poor judgment. But my friends, it's so much worse than that."

  • TIRED BRAINS CRAVE STIMULATIONS TO WAKE UP

    • Drugs, stimulants

    • Caffeine, nicotine to start and continue the day

    • Resorts to seeking depressants at night

      • Alcohol sedation is a biological mimicry of sleep 

        • actually harms neurological processing (of memory consolidation and recall)

  • SLEEP LOSS => WEIGHT GAIN 

    • 50% chance of being obese [definition] for those who sleep 5 hours or fewer per night. 

    • Sleep loss activates a hunger hormone called gherlin 

      • seeks carbohydrates and sugars specifically 

  • STRESS links metabolic predisposition and tiredness

    • Stress also worsens memory loss 

    • A little stress here and there is okay 

      • It's sustained stress that disrupts sleep and suppresses immune function 

        • Tired people have overall rates of higher infection, higher rates of diabetes (because high stress causes glucose intolerance.) 

        • Stress raises blood pressure and increases cardiovascular disease 

  • Our body is constantly sending us signals. Our bodies talk to us. 

  • BENEFITS OF GOOD SLEEP 

    • increases your concentration, attention, decision-making, creativity, social skills, health

      • If you get sleep, it reduces your mood changes, your stress, your levels of anger, your impulsivity, and your tendency to drink and take drugs.

  • HOW TO SLEEP PROPERLY 

    • Wind down ! ! !  

    • make your bedroom a safe haven for sleep

      • as dark as possible and slightly cool 

        • reduce the brightness of the light you are exposed to about half as dim as it is during the daytime!

          • The idea that dim light "strains your eyes" or is bad for your vision is an old wives tale. It is not true.

          • Dim your lights at least 30 minutes before bed, but "I personally prefer to get the light in my home to match the light around sunset, and then I just keep it there until bed. In a way I am tricking my bed to think that I am going to sleep just after sunset every night."

        • "Light increases levels of alertness and will delay sleep." 

    • Most of us go into the bathroom before going to bed, often the most brightly lit room in the house. If your home doesn't come with dimmers, you don't need any more light than a plug-in nightlight. 

  • Waking up: Light exposure in the morning is important and must be sought out, not cowered from!