NEURO: Fast Facts

NEUROLOGY: FAST FACTS

We thought the following facts about the brain would be interesting to know. Enjoy!

268: Equals speed, (in mph) at which signals travel along an alpha motor neuron in the spinal cord. It is the fastest such transmission in the entire human body. Sensory receptors in the skin, which lack the speed boosting, insulating layer of tissue called "myelin" are one of the slowest clocking in at 1 mph.

100,000: This is the total miles of myelin covered nerve fibers found in the average human adult, 20 year old brain. Neuroscientists at UCLA, who have been studying myelination in the brain of adults aged 23 - 80, reported in September, 2010 that the coating peaks around the age of 39. That's the same age at which participants hit top speeds in standard testing for motor abilities.

100 Trillion: This is the mimimum number of neural connctions, better known as synapses, in the human brain. To put this number in perspective; that is at least 1,000 times the number of stars in our galaxy. British researchers reported in Sept. 2010 that genes involved in the workings of synpases account for about 7% of our entire genome.

50: This is the depth, in nanometers, of the smallest grooves detectable by a human fingertip. Most of the 2 billion or so nerve endings in the outermost layer of our skin sense pain. Those dedicated to tempeature allow us to detect differences as small as 0.01 degree Farenheit.

2000: Number of slices from the cerebral cortex of a mouse by Harvard scientists. The researchers will image each slice under an electron microscope and then build a 3D picture of all of the brain's connections. Someday, similar maps of human brains will be built and may yield clues to mental illness, memory and loss of memory as well as personality traits.

1,000,000,000: Is the number of neurons, linked by 10 trillion synapses, in a brain simulation developed by IBM and Lawrence Berkeley National Labs, running on the DAWN SuperComputer. Researchers are now testing hypotheses about how the human brain really works. The real human brain contains about 100 Billion neurons so scientists are getting close, in at least raw numbers anyway.

* Information gleaned from Discover Magazine, March 2011. 

Dr. John Haberstroh is a Somerville and Boston Chiropractor. Find us at -BostonSpineClinics.com