Spinal Cord and The Sense of Touch: What's the Connection?

Human beings have Touch receptors located in varying densities over our bodies. In the hand, touch receptors are most densely located in our fingertips, which is why our fingers are more sensitive to touch than our palms. There are two pathways that touch takes to the brain. The spinalthalamic pathway is the slower of the two pathways, however, it is the route from the spinal cord to the brain which carries most of the information regarding skin temperature and pain. That is why when we become ill and have a fever, it is not necessarily detected right away. Or if we burn ourselves on the stove, the pain might increase a day or so after the initial incident. The pain takes time to travel.

On the other hand, the dorsal-column-medial-lemniscal (DCML) pathway is the route from the spinal cord to the brain which carries signals from skin, muscles, tendons and joints. This is due to wider-diameter axons and fewer synapses which, therefore conveys messages and information more quickly to the brain. For example, my right knee gives me a lot of pain on a fairly consistent basis. When I hear my right knee crack or pop, I know that I will feel a significant amount of pain shortly after. Since the pain is in the joints or tendons of my knee, I feel it quickly. The spinal cord is the most important piece of the nervous system. It can be life-changing to have spinal cord damage, especially the higher up the injury is. For instance, Superman Christopher Reeve suffered fractures to the top two vertebrae, which is considered the most serious of cervical injuries, which also damaged his spinal cord. He could not move anything below his neck, and he was barely able to turn his head if at all. He was unable to feel any part of his body below his neck and was hooked up to a respirator for the 10 years following his injury ultimately resulting in his passing. The lesson here is to be very careful when dealing with a spinal cord injury. If there is a chance for you to lose feeling below the waste, the activity is probably not worth the time.

Ross

Perception of Film

A persistent image from Sony Pictures 2008 motion-picture
Nick and Nora's Infinite Playlist.

With respect to the perception of realism when viewing motion pictures, persistent images prevent us from seeing that motion-picture screens are dark when the projector moves from one frame to the next. Persistent images last an average of approximately one quarter second after the stimulus has been removed. Perception occurs with short exposure time because the persistent image keeps the image available to the viewer slightly longer than the actual presentation time.

Persistent images are crucial to the perception of realistic motion-picture and television pictures. When motion picture films are projected, it is mandatory to darken the screen with a rotating shutter when the film is being moved from one frame to the next. In other words, the persistent image prevents the viewer from seeing the dark intervals which would appear as a flicker in the theater.

Earlier motion-pictures were nicknamed flicks because of they were made with 16 frames per second and the flicker was obvious to the naked eye. Because images are constructed sequentially with an electron beam, the persistent images are necessary for the viewers to see a complete picture. The duration of a persistent image may vary depending on several factors including the image's luminance level and whether the removal of stimulus is followed by another image or darkness.

A Typical Day at Wrigley

Take me out to the ball game, take me out to the crowd, buy me some peanuts and Crackerjacks, I don't care if I ever get back, for its root root root for the Cubbies...

I love nothing more on a beautiful day, then sitting in the stands at Wrigley Field, watching the Chicago Cubs, and enjoying the various stimulants offered for my enjoyment. It starts as I walk up Clark street toward Addison and I am bombarded with peanut vendors. Of course you have to get a bag of peanuts if you're going to the game. This is just the beginning. Once I'm inside the park, my first order of business in getting a beer. Peanuts and beer go hand in hand, but the intoxicating aroma of grilled onions accompanied by charred brats and dogs is so temping that I have to force myself to find my seat before I can indulge.

Sitting in the stands is what gives Wrigley Field its undeniable power. I sit and I smell beer, hot dogs, onions, nachos, cotton candy, peanuts, fresh cut grass, and I am consumed by Cubs baseball. There is a natural comradery in the stands! You don't have to know people in order to fit in, you just have to participate in the conversations heckling the visiting teams or discussing how the Cubs are sucking it up like usual. When you're a true fan like myself, it is almost second nature to be making fun of the Cubbies, and the next thing you know "POP" the ball is blasted in to the bleachers. The crowd rises from their seats filled with joy that we witnessed a home run by our team and puts an end to our bad mouthing. I begin giving high-5's to my fellow fans surrounding me because we are all in attendance for the experience. Like I said, this is how the natural comradery comes into play. The next thing I know, I hear "Cold beer here!" being yelled by the vendor passing by, so I raise my hand and yell "Two Bud Lights!" And that is how it is done.

As a fan and spectator, you have to be aware of your surroundings in order to take full advantage of the numerous luxuries offered at every game. I use my perception of sight, sound, vision, touch, and taste at every single game I attend, adds to my joyful experiences at Wrigley. After several innings of peanuts and cold beer its time to head to the bathroom that reeks of stale beer, cigarette smoke, and urine to drain my lizard. On my way back I use my nose like a German Shepard to follow the scent of grilled onions and finally get to engorge myself with jumbo charred hot dog with mustard. I make it a point to get my last beer at the park and nachos with extra jalapenos right before the start of the seventh inning, because they stop selling beer after the inning is over.

If the game ends in a victory for Chicago, I participate in singing Go, Cubs Go with my fellow patrons as I proceed out of the park by following the herd. So you see, all five senses are stimulated and come into play when enjoying a beautiful day at Cubs baseball at Wrigley Field!


Ross

Artistic Applications of Taste!

Why does food taste so damn good? Ooh, I have a better question; Why does food that is bad for our health taste so good? Actually, the question I really am dying to have answered is; Why does food that might not look so appetizing, taste so phenomenal that it must be from a different planet? I don't really know the answer, but I do know that even though sushi is now my favorite food, I used to hate it!

When I was about eight I tried sushi for the first time with my family at my brother's birthday dinner. We ate at a restaurant called Hanabi in Buffalo Grove, Illinois and I absolutely dreaded going out for sushi with my family. I couldn't stand the stench of raw fish that filled the restaurant or the fact that there was nothing cooked on the menu. I resorted to making fried rice by combining white rice with soy sauce. The part I hated most was this green condiment known as wasabi. My brother along with both parents would load the wasabi up on each individual piece of sushi. I would always laugh when their faces turned red or when they would use a hand to fan themselves because of the overwhelming curve ball wasabi threw. I was so scarred to taste it because I had seen Ted Danson in the movie Made In America, unknowingly eat an entire ball of wasabi! It was a hilarious scene, but it frightened me for several years.

When I was 13 I went through a phase where I wouldn't consume any type of food without smelling it first. My family went to Hanabi again for my brother's birthday and I had a cold that block my sinuses, therefor, I was unable to smell anything. I decided to try something simple I began eating fake sushi such as California Rolls and Ebi Nigiri with a little bit of wasabi. Anything with shrimp tasted and smelled good to me now. Moments after taking my first bite, I noticed my sinuses opened up and I was able to smell and taste simultaneously. I realized that my taste buds were expanding, because now all of the sudden I like sushi. From that point on, I had no problem going with my family to eat and Hanabi or any other sushi restaurant. As I grew older and wiser, my taste buds expanded even more and I began liking raw fish, and progressively adding more and more wasabi to my sushi. I no longer smell my food before I eat it.

The point I am trying to make is that looks may be deceiving, but you cannot judge a book by its cover. Even though good sushi is prepared moments before consumption, presentation is almost just as important as taste and smell. Artistically speaking, it is possible for a particular food to look delicious, but taste absolutely dreadful! I know there is a connection between smell and taste, and my personal life experience has proven this fact. I cannot smell without my sense of taste and vice verse. The two senses go hand in hand. With regards to taste and sight, It is easy to make the mistake, assuming that food which may look appetizing probably tastes good too. Wrong!!!!

Challenge: Try some type of food that does not look very appetizing and you be the food critic. Perhaps an "F" for presentation and an "A" for taste!

Ross

Genetics of Taste, Is it Hereditary?

Personally, I know for a fact through my own life experiences that I don't have the same taste buds as my parents. My dad loves spicy food and so do I, but he also loves radish. I hate radish, and I can barely stand the taste of horseradish when it compliments my Gefilte fish. So the question that still remains is: Are the genetics of taste hereditary?

Well let's think about this for a second. If the genetics of taste were hereditary, wouldn't that mean that I should have the same, if not similar taste buds to my parents? I think I should, and so should my brother, but we do not! I like a lot of things that my brother likes, but he has a much wider range of taste buds than I do, compliments of spending five months studying and traveling through Europe. He is cultured, a little more so than I, therefor I believe that upbringing and life experiences contribute to the expansion and acquisition of new taste buds.

It has been scientifically proven that humans show substantial differences in taste sensitivity to many different substances. Also, recent advances in the understanding of taste at the molecular level have provided candidate genes that can be evaluated for contributions to phenotypic differences in taste abilities. In other words, the more we can understand the molecular composition of taste buds, the more we will know about the genetic differences involved in distinguishing taste.

I believe that taste is somewhat hereditary in regards to upbringing, but not necessarily connected to our parents through genetics. As young children, our parents feed us based off of what they were brought up with, as well as, what our parents like to eat as well. If my parents hate McDonald's, they will most likely not feed me McDonald's. Do you catch my drift? Upbringing and life experiences are more important to developing a sense of taste than the genetics I acquire from my parents.

Challenge: I challenge all my followers to try taste something new, even though you may have tried it in the past and not liked it. You may be surprised at what you discover!

Ross

Different Theories of How We Smell?

The sense of smell, scientifically known as olfaction, uses a sensory organ (nose) to pass scent information on to the olfactory cortex in the brain. Diffuse suspensions of relevant molecules, called odors, are analyzed by the nose using a molecular lock-and-key scheme whereby odors are identified by their unique chemical signatures. Some odor are stronger or more potent than others. Odors in the purest form are much stronger than odors combined in a chemical composition.

Olfactory receptor neurons, are the cells responsible for smell, and are located on a 1-by-2 inch strip of tissue called the olfactory epithelium. The olfactory epithelium is located about 3 inches above and behind the nostrils. The human olfactory epithelium is roughly 16 cm², contrast with some dogs which have 150 cm². This obviously adds the theory behind dogs having a keener sense of smell.

The sense of smell evolved as a means of detecting survival-relevant information about the external world, especially appraising food. Animals such as dogs use their sense of smell for marking their territory as well as finding a mate. Smell is the oldest of the senses, with analogues dating all the way back to the first animals 600 million years ago. One of the five primary senses, smell is most deeply associated with the formation of memories. Dogs use their original memory of a scent to distinguish between safe and dangerous territory.

Humans use smells to refer to memories as well. I will never for get the smell of my gym bag from high school or my moms signature perfume. The smells we encounter in our life are connected with memory of a specific scents initial introduction.

Neurons Communicting w/ Muscles

Most neurons communicate with other neurons or muscle by releasing chemicals called neurotransmitters. When dealing with muscle movement, Acetylcholine (ACh) is one of the best-understood neurotransmitters. ACh is the chemical messenger at all junction between a motor neuron and skeletal muscle. The muscle contracts when ACh is released into the blood stream.

Basically, with these Acetylcholine neurotransmitters, our muscle will not contract. Anyone ever seen the movie Ace Ventura: When Nature Calls starring Jim Carrey. The members of the Wachati and Wachootoo tribes of Nibia, a fictional African country both used piousness hunting darts. Although the tribes and country are both fictional, certain South American Indians would apply a poison called Curare that occupies and blocks ACh receptor cites preventing the neurotransmitters from affecting the muscles.