I Ain't Scared of You

Toxoplasmosis.  If you are pregnant or are planning on becoming pregnant, this is one parasite you should know about and work hard at avoiding. It can pass through the placenta and negatively affect a growing fetus.  The consequences vary from mild to devastating.  It is transmitted to humans through cat feces.  It can be contracted from cleaning a cat litter tray, eating raw or undercooked meat, drinking unpasteurized milk, eating unwashed vegetables, working in the garden without gloves, or from exposure to a child's uncovered sandbox.

Dr. Rober Sapolsky calls it "Toxo."  He is a leading neuroscientist who is a professor of biology and neurology at Stanford University, as well as a research associate in Kenya.  He has received numerous awards for his scientific studies.  Here is an interview with him talking about Toxo.  It is fascinating and about 24 minutes long.  Well worth watching every minute, in my opinion.

In the life cycle of this parasite, it reproduces in the gut of a cat.  The eggs are shed in the feces, which are then picked up by rats and other animals that just might get eaten by a cat.  Toxoplasma forms cysts throughout the rat, including the brain. And yet a rat that is infected with it is perfectly healthy. That makes good sense for the parasite, since a cat would not be particularly interested in eating a dead rat. But scientists at Oxford discovered that the parasite "changes the rats in one subtle but vital way."

Rats respond negatively to the smell of a cat. The stress response in the rat goes up, and his instinct is to avoid the area where the smell was detected.  Makes sense.  When a rat is infected with Toxo, and smells a cat, the fear circuit in the rat does not activate.  Not only is he not afraid of the cat, but the sexual arousal circuit is activated slightly.  Wow!  This parasite has figured out how to get back into a cat so it can reproduce!  Just make the rat want to be around the cat, who will eat him.

When scientists in the UK looked at the genome (the genes and DNA) for Toxoplasma, they were astonished to find two versions of a gene that makes dopamine.  Dopamine is the neurotransmitter in the brain that is all about reward and anticipation of reward.  It is involved with emotional response, and the ability to experience pleasure and pain.  So in other words, this parasite has the gene that allows it to plug into the reward system of the brain.

So what about humans?  Can it affect our brains?  Besides the disaster of Toxo getting into the nervous system of a pregnant woman and her fetus, there are other things that go on in humans.

The first part of the infection might have symptoms like inflammation, sore throat, just not feeling well.  Then those symptoms disappear.  This is when the cysts form in the brain. For a rat, it is when the parasite makes the dopamine and the strange behavior of seeking out a cat occurs.  In men who are infected, their behavior can become impulsive.  Women less so.  There are two different groups, independent of each other, who have studied this and find that men who are affected are 3 to 4 times more likely to be killed in a high risk activity, such as reckless speeding in a car.

The personality of humans being changed by some invading organism is not a rare pattern.  The rabies virus changes both animal and human brains to become more aggressive. It knows how to make the host want to bite someone and pass on the particles of the virus.  And this parasite knows how to perpetuate its existence.

There are other areas that are being studied as having a possible link to Toxoplasma.  One is schizophrenia.  There is too much dopamine in the brain of a schizophrenic, and there is some evidence of a rate of increase to children whose mothers had cats when she was pregnant.  There are also questions about "cat women" being infected.  Scientist are still studying these and other aspects of this condition.

Now you have heard something interesting.

To Feel Nothing

Hansen's Disease, formerly known as leprosy, still exists around the world.  Since the development of medicines for it, it is no longer a fatal illness, nor has is it ever been highly infectious. It is a chronic illness.  The incubation period is anywhere from nine months to 20 years.  That makes it very difficult to pinpoint where or when one has been exposed to the disease.

The bacteria that causes Hansen's Disease prefers the parts of the body that are cooler -- the earlobes, the nose, the fingers and toes, and the eyes, though it can be anywhere on the body.  It resides in the nerves and damages them.  Where the sores are -- there is diminished or no feeling.  The devastating thing about the eyes being affected is that the blink reflex is lost.  Without blinking, the eyes dry out and foreign matter is not washed away.

This is a picture of a Belgium priest named Father Damien who spent sixteen years on the island of Molokai in Hawaii caring for the lepers who had been exiled there. He contracted Hansen's Disease and died in 1889 at the age of 49.

There is a book called "The Colony: The Harrowing True Story of the Exiles of Molokai" by John Tayman.  It is a very interesting read.  This quote from the books shows some ingenuity.

"Doctors tried training patients to blink on schedule, using a timer or some other device. The technique worked in some cases, but only if the patient was physically able. Leprosy bacilli also attack the nerve controlling eyelid muscles, creating a condition known as lagophthalmos, in which the person is unable to close the eyelids. In such cases surgeons rigged a thread of muscle from the jaw to the lid, which caused the person to blink as he chewed - doctors then handed them a pack of gum."

Now you have heard something interesting.

Left or Right?

When you pick up an infant, is it more likely for you to hold the child in your left arm or your right?  It has been found that 70-80% of women, regardless of which hand is dominant, hold babies with their left arm. 

Dr. Karl on a Triple J podcast pointed this out.  He said that with the help of physicians, mothers were studied quietly.  After examining an infant, the doctor would return the infant to the mother to the midline of her body.  Not toward the left nor the right.  The majority would take the baby and hold the child in her left arm. 

There are many different studies that I have read.  There seems to be two ideas about why this side preference might occur.  Some state that intuitively and subconsciously moms have figured out that the baby is more calm on the left side.  Before birth the baby can hear the mother's heart beating and it is a familiar, comforting sound. After birth, the baby can hear the mother's heart beat better when being held on the left side. This conclusion has many critics and is not well supported.

Many more studies believe that the left-side preference has to do with holding the baby on the side of the body that connects to the part of the brain which is dominant for processing emotions.  A mother is then better able to read the emotions of the child and react better. 

One of these studies found that mothers who cradle the baby on the right side speak higher and louder to their child than those who hold on the left.  Some mothers go back and forth between holding right and left.  Their pitch and volume went up when holding on the right.

There have also been studies about which side people prefer when hugging or kissing.  The majority of people tilt their heads to the right when kissing, and approach another person's left side when hugging.  Some of these reports think that the left-side baby cradling preference and the left-side approach to hugging are related.

There are many, many sites with this information.  Here are a few links. 

General overview
Do you kiss to the right or left?
Hugging preference
Pitch and volume differences
Left-sided baby cradling preference studies done on great apes.

Being right-handed, I always thought that I held my children on my left hip so that I could use my right hand to do things.  According to these studies, right-handers in general feel the same as I do.  And left-handers say they cradle on the left because that is the stronger arm.  It turns out it all might come down to our subconscious knowing the best way and our conscious mind coming up with a reason.

Now you have heard something interesting.

Can You Hear that Color?

Have you ever heard of synesthesia?  It is an accident of nature that would be fun to have.

Synesthesia is when two different senses are abnormally joined.  For instance, some synesthetes always see a certain color when they hear a certain musical note.  The most common form is colored numbers or letters, but any combination is possible.  There is a report of one man who tasted chocolate when he said his wife's name.  Another man claims that cucumbers taste pink.

Every synesthete experiences things uniquely.  For instance, one who sees an A major chord as purple, always sees it as purple.  But another might see that sound as yellow.

"I could never figure out why I was such a poor student at Math, until I received a 32 color pen for a present. FINALLY NUMBERS WERE THE RIGHT COLOR, 2 was yellow, 3 was green, 4 was orange, 5 was red, and so on. My teacher thought I was nutty, but when she invested in colored chalk, my Math scores SOARED... she just had to get the colors right. Oddly another student and I got into a fist-fight because he thought 3 should be blue, and 8 should be green... I won, and I made him cry, too..."

Estimates of the frequency of synesthesia range from 1 in 250,000 to 1 in 2,000.  Some famous people have this condition.  Most seem to be creative, such as musicians and artists.
Leonard Bernstein
Duke Ellington
Billy Joel
Stevie Wonder
Eddie Van Halen
Jimi Hendrix 
Frank Lloyd Wright
Victor Hugo 

Synesthetes tend to be:
Women: in the U.S., studies show that three times as many women as men have synesthesia; in the U.K., eight times as many women have been reported to have it. The reason for this difference is not known
Left-handed: synesthetes are more likely to be left-handed than the general population.
Neurologically normal: synesthetes are of normal (or possibly above average) intelligence, and standard neurological exams are normal.
In the same family: synesthesia appears to be inherited in some fashion; it seems to be a dominant trait and it may be on the X-chromosome.

The causes of synesthesia remain unknown. Some scientists have suggested that everyone is born synesthetic but that as the brain develops, the different areas become segregated.  It is not known why synesthetes retain these connections.  There might be a biological answer, because the condition tends to run in families.

For further reading, you might enjoy these books.
The Man Who Tasted Shapes by Richard E. Cytowi
Wednesday Is Indigo Blue: Discovering the Brain of Synesthesia by Richard E. Cytowi

Now you have heard something interesting.

Northern Lights

I have always been fascinated with the Aurora Borealis, also known as the northern lights.  It has been my dream to go to Alaska or somewhere in the northern latitudes and see them someday.  Citizens of Fairbanks, Alaska, at a latitude of 65 degrees north, can see the Northern Lights an average of 240 nights a year!

One night a few years ago, I went outside in my back yard and was a little mystified at what I saw in the sky. It was well past the sunset, but the sky in the West had streaks of red as if the sun were just going down.  And the sky in the East had streaks of red as if the sun was about to rise. It was absolutely beautiful! I just stood outside and gazed in wonder at the spectacle.  In fact, it took me a while to figure out what it was that I was seeing. Those northern lights coasting farther south than usual.

I live in Pleasant Grove, Utah, (about 30 miles south of Salt Lake City) at a latitude of 40 degrees North.  Although it is not normal for the northern lights to drift this far, during very large auroral events, they have been seen as far south as Mexico City.  It is a rare sight there.

There is a podcast that is enjoyable to listen to called The Naked Scientist.  It sounds intriguing, but there is nothing a child shouldn't hear in this podcast.  The other day they described what happens when the northern lights are visible.

The sun has bursts of energy called solar flares.  A solar wind carries these charged energy particles from the sun and they collide with the Earth's magnetic field.

This collision produces the lights.  It generates as much as a million megawatts of electricity.  One megawatt will supply enough power to sustain 1,000 averages households for one year.  So a million megawatts would power one billion average households for one year!  A small part of this electricity causes discharge in the upper atmosphere and creates light much in the same way as a neon sign creates light. The kind of atom in the solar wind determines the color. 

*The aurora in the southern hemisphere is known as the Aurora Australis.  It is almost a mirror image of the Aurora Borealis.
*Auroras have also been observed on Jupiter, Saturn, Uranus, Neptune, Mars, and Venus.
*The aurora gets its name from the Roman goddess of dawn.

Now you have heard something interesting. 

Vestibular System and Hyperactivity

It is so satisfying to me to learn something new, and then run across a reference to it from some other source.  Today I have a great example.  In my very first blog post in January, 2010, the subject was the vestibular system.  It is the part of the inner ear that does not process sound, but rather helps with balance, movement through space - even in the dark, response to gravity, sense of space, etc.  I loved learning that.

Last month I finished reading a book called "Emergence" by Temple Grandin.  She is a woman who has a Ph.D and has "recovered" from autism.  In one of the stories of her memory as a child, she relates how she went to a fair and ended up on a ride where one stands by an outside curving wall, the ride spins around very quickly, and then the floor falls away.  She described her fear and the overwhelming amount of sensory input.  Then, surprisingly, it became relaxing to her.  One sentence in the story caught my eye.  She referred to a study that has been done recently of the benefits of spinning in an office chair a few times a week for a child who is hyperactive and how it calms them.

Well, that got my attention! But she did not source the study or give any more details.  So I went to the Internet and have been reading many pages on the vestibular system and how it affects us.  I did not find the study that she mentioned, but I did find some interesting things.

"Children with overactive vestibular systems prefer slow movement, avoid risk-taking and avoid activities that require good balance and fast movement. They are fearful of falling, elevators, going up and down stairs and being tipped upside down."



Children with an underactive vestibular system "enjoy fast spinning and swinging. They enjoy jumping, partake in dangerous activity and move while sitting."  This constant movement is the body trying to wake up the vestibular system.



Just some food for thought. Kids who fidget in class are actually doing something good for their learning.

Do you think your vestibular system is just right, overactive, or underactive?  I definitely have an overactive one. I get motion sick in IMAX theaters.  When we went to see Avatar, I was looking at the exit because I was so sure I would need to run to the restroom.  In fact, in reading about this, I came across an article with information about others who have had the same problem.  I also get dizzy if my husband spins me around while we are dancing.

Here are some links for further reading.

http://vestibular.org/vestibular-disorders/symptoms.php
http://spectrumcenter.net/addadhd.html
http://www.smartcoach.us/VestibularandADHD.aspx
http://www.newhorizons.org/spneeds/adhd/nicholls.htm

Now you have heard something interesting.

Hotter Than White-Hot

A black hole can be formed when a star comes to the end of its life and collapses in on itself.  Its size is small but its mass is quite large.  But even more amazing is that its gravitational pull is so strong that not even light can escape. Did you know that light can be affected by gravity?  So it is called a black hole because it looks like nothing is there.  No light reflects from it. 

Here is a little clip of a renowned astrophysicist named Neil deGrasse Tyson talking about black holes.

Sgr is the abbreviation for the constellation Sagittarius. Here is a picture taken in the direction of Sagittarius.

This is a picture of Sgr A* (pronounced A-star) which is a supermassive black hole in the middle of our Milky Way galaxy. The light shown is not visible light, but by a very long x-ray exposure.  This image was taken by the Chandra X-Ray Observatory.  The red gas on the upper right and lower left part of the image is of 20 million-degree Centigrade gas that is extending over dozens of light years away from the black hole. It is the remnant of a "meal" the black hole had dozens of years ago.  So the light has had time to travel dozens of light years away

This supermassive black hole has a mass of 3 million times that of the sun.  Mass does not refer to the size, but rather the weight an object.  A block of gold has a greater mass than the same size block of styrofoam.
Black holes can not be directly observed, but rather the evidence around them infers their presence.  For 16 years, scientist have been tracking 28 stars as they orbit an invisible point. 

The event horizon of a black hole is basically the point of no return.  Past that, there is no escaping the gravitational pull, even for light.  When matter falls or is pulled into a black hole, it gets hotter and hotter and when it reaches a few million degrees Kelvin (another temperature scale) it emits x-rays. Click here for a more detailed explanation.

The spectrum of light, when put in order by wavelength from longest to shortest, goes like this: radio, microwave, infrared, the visible region we perceive as light, ultraviolet, X-rays and gamma rays.

So you could say that it isn't red hot, or white hot, but x-ray hot!

Now you have heard something interesting.