Download Brain Facts

Random Brain Facts
Random Brain Facts
• We’ve learned more about the
brain in last 20 yrs than all time
previous to that
• No two brains are identical
• Brain is mostly water (78%), fat
(10%), and protein (8%)
• Living brain is so soft it can be
cut w/ butter knife
Random Brain Facts
• The adult human brain weighs
about 3 pounds (1,300-1,400 gm)
– Elephant brains = 6,000gm
– Cat brains = 30 gm
• Brain is ~2% of body weight, but
consumes ~20% of body’s energy
• Total surface area of cerebral cortex
= ~2.5 sq ft
• Bigger brains are not necessarily
better
• Einstein’s was average size
Random Brain Facts
• Human brain has ~100,000,000,000
neurons
• If all neurons were stretched end to
end, would reach to moon and back
• Every second, brain receives 100
million messages from the senses
• ¾ of body’s neurons are in brain
• On day you are born, all brain cells
are in place
– They’re just immature – still developing
• Explains why don’t have memories until ~3-4 y.o.
– Will not regenerate – this is all you get
• (Recent research is challenging this idea…)
Random Brain Facts
• ~10 trillion pieces of information in
the brain
• There are 1,000 – 10,000
synapses for a typical neuron
• Human brain is capable of
processing
10,000,000,000,000,000,000,000,000,000
bits of data per second
• Intelligence has nothing to do with
number of neurons – it has
everything to do with number of
dendrite connections
Random Brain Facts
• World record for time w/o sleep:
• 264 hours (11 days) – Randy Gardner, 1963
• Unconsciousness occurs 8-10 sec after loss of
blood supply to brain
Random Brain Facts
• Changing brain:
• 525 billion neurons in brain at 26 wks
gestation
• 200 billion on day born
• 100 billion today
• Brain is ultimate “use it or lose it”
machine
– “neural sculpting” happens during REM
sleep
• Computer/TV has huge impact on
brain
• Recommend no TV/internet 0-2 yrs
– Sesame Street?
Random Brain Facts
• Humans can process 400-600 words/min
– Talk about 100-125 words/min
• Speaker needs to fill in gaps to avoid boredom, mind
wandering
• Older people take longer to learn, but retain
information as well as younger ppl
• Before age 5, brain is very plastic – can
simultaneously adapt after injury
– After age 5, severe, permanent damage more likely
• Ex – 5 y.o. boy w/ severe seizures had entire left hemisphere
removed – paralyzed on right side, but scored above avg on
intelligence tests, finished college & grad school – today an executive
Random Brain Facts
• Brain disorders cost
Americans more than $600
billion a year
• Alcohol use in teens
devastating to the pre-frontal
cortex
• Mature neuron has
myelin sheath protection,
young adolescent brain
does not
– MN in top 5 for alcohol
consumption
– Also top 5 for FAS cases
WARNING:
REALLY CORNY JOKES
AHEAD
Bad brain jokes
• What does a brain do when it sees a friend
across the street?
– Gives a brain wave
• What did the hippocampus say during its
retirement speech?
– Thanks for the memories
• What did the right hemisphere say to the left
hemisphere when they couldn’t agree on
anything?
– “let’s split”
Bad brain jokes
• What happens if you break the brain
scanner?
– You will have a CATastrophe
• What kind of fish performs brain
operations?
– A neurosturgeon
• What do you call a skull without 100 billion
neurons?
– A no brainer
Bad brain jokes
• When does a brain get afraid?
– When it loses its nerve
• Why didn’t the brain want to take a bath?
– It didn’t want to be brainwashed
• Why was the neuron sent to the principal’s
office?
– It had trouble controlling its impulses