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

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