BRAIN
Made of thousands of neurons
When humans sleep, the neurons oscillate into waves picking up electrical activity
Large waves when sleeping
Smaller and irregular waves during wakefulness
SLEEP - ⅓ of our lives are spent sleeping
Restoration of cellular processes
Important for memory and creativity
Hypothalamus - Controls the onset of sleep
Thalamus - Prevents sensory signals from reaching the cortex
Hippocampus - A memory region active during sleeping
Amygdala - An emotion center active during dreaming
Reticular Formation - Regulates between sleep and wakefulness
Pons - Helps initiate REM sleep
NEURONS
Neurons - Axons - Dendrites - Synapses
Neurons can be produced in adulthood, but are usually set for life
Neurons are high-demand cells and susceptible to imbalances such as oxygen, glucose, toxins, physical damage, etc.
Loss of key proteins, synapses, axons, dendrites can affect neuronal function either acutely or severely for months or years before neuron death
When a neuron dies, it cannot be replaced.
People can live for years and not realize dysfunction at the physiological level
GLYMPHATIC SYSTEM
Glial cells (non-neuron cells in the brain)
Brain disposes of six pounds of waste a year
Astrocytes: Star-shaped cells interact with blood vessels and neurons
Microglia: brain’s specialized immune cells; can be protective or damaging; exists in different states.
Microglia can engulf synapses if the bridge needs to be broken
Space between the cells increases by 60% during sleep periods
Pulsations drive cerebrospinal fluid around the brain and help to sweep away waste
Disrupted glymphatic now linked to dementia in humans
The glymphatic system is evidence sleep helps to clear toxins from the brain, adding protection against diseases
WHY MUST WE SLEEP
Homeostasis - longer we stay awake, we build sleep pressure
Sleep circadian rhythm - a daily rhythm that controls the sleep-wake cycle
The parasympathetic nervous system activates
Body temperature drops
Breath and heart slow
The biological clock interacts with time givers and cues
The biological clock is made up of neurons
Cells electrical firing and metabolic activity is rhythmic on 24-hours
STAGES OF SLEEP
STAGE 1: Alpha waves
STAGE 2: Deeper, 5-15 minutes, and the brain spikes
STAGE 3: Large Delta waves
STAGE 4: Deepest sleep, 20-40 minutes (cat naps anyone?), then returns to stage 3, 2, 1
ENTERING RAPID EYE MOVEMENT - REM
REM
Beta waves
Brain in awake-like state
Roughly 30-50 minutes
Approx 25% of sleep is REM
As active as an awake brain
Cycle repeats throughout the night
Dreaming: illusions
The sympathetic arm of the autonomic nervous system activates
PONS is a conduit sending messages to the left and right sides of the brain and initiates REM
Motor neurons fire to the muscles when awake but paralyzed while sleeping
Ever seen the movie Inception???
SLEEPING FOR MEMORY
Neurons talk to all the cells in the body and muscles
Immune cells and neurons hold memories for patterns
During sleep, memories are consolidated, or transferred to long-term storage (hippocampus).
Brain replays events of the day
The hippocampus talks to the cortex during sleep cements new synapses
The brain integrates new information with existing; key component to creativity
If you have an issue or need clarity, sleep on it.
BRAIN ILLNESSES
The brain shrinks with age - neurodegenerative diseases
EPILEPSY - Neurons start picking up other energies
Stroke
Autism
Schizophrenia (could also be genetic)
Depression and Anxiety
Multiple Sclerosis
Amyotrophic Lateral Sclerosis
Alzheimer’s disease and dementia
Huntington’s disease
Parkinson’s disease
YOGA FOR THE BRAIN
The bedroom should be very dark
No caffeine after noon
Regulate sleep hours
Cool temperature
Sleep in bed only
Minimize light
Stop eating at least two hours before bedtime
Langhana practice of yoga - reduce energy
Exercise:
For seven days, write down what time you wake up and what time you go to sleep.
Write down what you do before you go to sleep
What will you implement in your life to increase your time to sleep?