Premenstrual Dysphoric Disorder

   As time has progressed we have seen the naming and identification of a variety of disorders. One of which is called Premenstrual Dysphoric Disorder (PMDD). You might have seen if briefly mentioned on some birth control commercials or on their websites as a footnote that their product treated this disorder. It wasn't so long ago that I myself was given a diagnosis as having PMDD, upon which the doctor ever so lightly wrote me a prescription for Prozac. After taking the medication for a year and not seeking any kind of mental health treatment I decided to discontinue use of the Prozac and attempt to refute the doctors diagnosis. It has been over a year since then I now I have chosen to enlighten the masses about this disorder.

    PMDD is listed in the DSM IV as a "depressive disorder not otherwise specified", with eleven criteria of which five need to be met before a diagnosis can be given. 

The story of David Reimer

 Throughout this section we learn about not just sex and partner preferences but also about hormones such as androgens and estrogens. These hormones levels are different in each sex. Males tend to have higher levels and androgens, such as testosterone, and females tend to have higher levels of estrogens. A topic that is briefly discussed in module 11.2 is that of gender identity later followed by gender assignment and rearing. Our text briefly mentions (in the later section mentioned) the case that I am presenting to you today. I would like to warn you though the footage I have attached could cause you to become upset or disturb you.

Be it due to lack of technology or lack of Dr. Money's interest in hormones and the affect they have on determining sex it can be regarded that he crossed certain ethical boundaries that should not have been breached. As you can recall (if you read the chapter) the "differentiation of external genitals and several aspects of brain development depend mainly on the level of testosterone." (Kalat, et al, 2009) If this knowledge had been known Dr. Money's theory on rearing could have had a strong opposition. Yet no such information from my knowledge was available when Mr. Reimer's parents were looking for a solution to his situation.  We come to understand as this section progress' that childhood behavior is impacted by socialization but not just that alone. In a study by Alexander, Wilcox and Woods in 2009 infants (of both sexes) were placed in front of an array of toys ranging from either feminine (dolls, tea sets), masculine (toy trucks) or neutral toys (crayons, etc). The infants used in this study ranged from ages of 3 to 8 months old. The researchers were able to gauge preference by the amount of times each sex looked at either the female, masculine or neutral toys. The end result being that the girl infants looked more at the dolls whereas the boys looked at the trucks or neutral objects. Now that being said it is easier to understand why Brenda had such a great deal of inner turmoil when it came to dealing with being a girl. 

 There are a few more videos in regard to David Reimer and his life; which I encourage you to watch. Learning about his story not only appalled me but brought to my awareness what gender confusion could be like and I hope that you will think twice before judging someone because they might look like a certain sex but adopt lifestyles of the other. 

Sense of Smell vs Pheromones

      Before I begin my topic of discussion I would like to state that the above clip would pertain to olfaction because he is using a cologne which involves olfactory receptors. And well I figured I would start you guys off with a laugh. 

     While reading this weeks assigned literature I was most intrigued by the section dedicated to pheromones. They are define by our text as chemicals released by an animal that affect the behavior of other members of same species. Examples that we are provided with included female dogs when they are fertile and women with regard to menstrual cycles. However, it is hard to think about pheromones and not wonder about the science of smell. While searching for clips on pheromones I came across what seemed a contradictory study in point of view. You can decide for yourselves after watching it.

 

       Now I am under the impression that pheromones can not be sensed with our olfactory receptors. Pheromones have their own set of receptors located in the vomeronasal organ (VNO). Our text wasn't very clear on how our body detects them. Now it is important to state that pheromones are not something that we can smell; pheromones affect us unconsciously and involuntarily. They are mostly used, in regards to humans, for sexual purposes. The above clip on a pheromone spray sold in adult novelty stores sways consumers to purchase their product because, it will make them irresistible to the opposite sex. As we saw in this instance it didn't work. The link above describes a study where a specific pheromone androstenone was tested for smell by a group of males and females. Reseachers first learned of pheromones through insects. We now know that plants also release pheromones to attract insect to help with pollination. With this link you can find some interesting differences between human and plant pheromones.

     With regard to olfaction we forget how important it is to species other than our own. I learned through a twitter feed an interesting fact about ants and how they have created graveyards which are kept occupied because of their sense of smell. Ants are able to detect oleic acid which is emitted when an ant dies. Upon smelling this the ants will move the body to a graveyard they have created to prevent their species from being infected by the bacteria that comes with decomposition. 

    It amazes me all that we don't know about the world around us, and how much we take for granted. Next time you use your nose or are strangely attracted to someone think about what your life would be without your sense of smell or without your vomeronasal organ. Sometimes having a sense of either one could mean your life. 

Remember, Remember...the self

       Have you ever wondered what your life would be like day to day if you were unable to create memories? What if you never even knew what a memory was and just existed day to day. I doubt you would be able to live more then a couple of days because, although few of us think about it memory is essential to our existence. Without it we wouldn't be able to learn what is good and bad for us and survive it unless we remember and stored that event in our brains. Below you will find 10 unforgettable facts about human memory.

        In our text in module 13.2 in the portion titled applications and extensions it mentions how in the 1960s and 1970s scientists tested the idea that maybe memory is stored in a specific molecule. Specifically the text mentions RNA or a protein. Now I find this interesting because a few minutes later I mention that concept to my biology major buddy who tells me about a theory (name of such theory unknown at this time). He stated that if ever you are some where different; in this example I live in South Texas and go to Mexico. Now if I am somewhere in Mexico and recognize part of the terrain although I have never lived there it could be a memory that is coded in my DNA because my ancestors lived there. Now our text did state that research wasn't pursued because of difficulty replicating the findings. However, it didn't state that it completely halted. In an article (published in 2008) I read while researching this idea I learned that scientists have since produced a theory that memories, specifically long term memories can be coded into our DNA by a process called DNA-methylation. Now I am no chemistry expert or one of DNA for that matter but the article is very interesting.

     I wouldn't be surprised if this topic finds its way back into formidable research labs and is proven that in fact memories can and are coded into a specific molecule. Imagine the possibilities!

Case of the Strokes?

     Throughout most of my blogs you see a common theme and that is human health awareness. In society today or at least in the United States we live such fast paced lives that we forget about the importance of eating healthy and maintaining a healthy lifestyle. In one of the video clips listed for our viewing for this section the female speaker was so passionate about the experience of her stroke and that moved me. What really caught my attention was that it took her EIGHT YEARS to recover. That is just shy of a decade. Now I am unaware of her situation but all I do know it that is a long time to recover.

     A stroke occurs when there is a blockage of blood to or through a part of the brain and/or from a bursted blood vessel. The way that the blockage is induced it either through narrowing of the arteries, an increase in artery pressure, blood clotting, or a tumor in the brain. Now there are many reasons why a stroke occurs ranging from family history to drug use and bad health choices. After the stroke individuals can loose function to parts of their bodies, have difficulties with speech, memory and thinking clearly.

    As I read through chapter 14 I was intrigued by the portion dedicated to brain damage and language, more specifically Broca's Aphasia. Broken down into a simplified definition individuals with Broca's Aphasia have difficulty speaking and problems with comprehending complex grammar. They do not  speak with the use of what we would deem necessary for a full sentence. In the video below is a female named Sarah Scott who suffered a stroke at the age of 18 while in her english class. Take notice of her speech.

      In the above video Sarah mention how everyday she goes to speech therapy. You will also notice that she has a pen and pad; with that I assume that she can write what she wants to say just can not speak it.  So that you can understand the extent of work necessary to help with Broca's Aphasia I would like for you to watch  the following video of Sarah three years after the one posted above. 

       I hope that you leave this blog more aware of the fact that such a thing that happened to Sarah can happen to us. Prior to reading Chapter 14 I quit smoking and I am working on getting out of obese territory. I hope that the link above and the following will make you more aware of the importance of living a healthy lifestyle. 

Sum-um-um-ummation

       In last weeks assigned modules we covered action potentials, hyper polarization and depolarization . If you were completely lost on the topic and would like a better understanding explained in roughly five minutes watch the video posted below for a brief recap so that you don't get lost while reading my blog.

The gentlemen in this video covers the materially clearly and concisely so you shouldn't get too confused when listening.

Before I begin my discussion on Excitatory Presynaptic Potential I want to cover summation and the two different types.

At the beginning of module 3.1 we learn about temporal summation; which is described as being "a cumulative effect of repeated stimuli within a brief time"(Kalat, 2012). Imagine your trying to break a concrete barrier with a sledge hammer. You hit the barrier once, nothing happens. You hit it again and again and again continuously and it cracks. In a sense this happens in temporal summation being that a stimulus is received down the axon of the presynaptic neuron when the the postsynaptic neuron receives that stimulus Excitatory Presynaptic Potential (EPSP) occurs however, the threshold for action potential is not reached. Yet, if more than one stimulus travels down that presynaptic neuron one after the other essentially action potential can be reached. 

With spatial summation more than one neuron can be touching the postsynaptic neuron and instead of it receiving stimuli information from just one axon it can receive stimuli from both one after the other which can be enough to cause an action potential in the postsynaptic neuron.

Leslie Samuel gives a more scientific understanding which parallels what our text says about temporal summation and spatial summation.

My reason for choosing this topic isn't only because it interest me; I chose it because it is so important. If Charles Sherrington had never thought about the speed of reflexes and delayed transmission , etc. we probably wouldn't have such a good understanding of certain psychological situations such as depression or drug addiction. It makes me appreciate the science of synapses because without this branch of neuroscience our ability to help those whose synapses malfunction would be limited.

Kalat, J. W. (2012). Biological psychology In L. Schreiber-Ganster & J. Hague (Eds.), Biological Psychology(11th ed., p. 582, 583). North Carolina: Wadsworth Cengage Learning

Got a Clue about Glue?

       Many a time I've heard that we only use 10% of our brains. Now when I first heard this years ago I accepted it. I did not question it because I trusted the source that was feeding me that information. Well, time has passed since then and I have come to learn that you can't trust everything you hear or read. I've learned that the only true sources to trust for information are from the direct source or researcher. Even at that there is always room for human error.

      Nonetheless, I reach my topic. Our text Biological Psychology, 11th Edition by Kalat has a brief portion in chapter two dedicated to the discussion of glia. What is glia you might ask? Well friends glia (also known as neuroglia) are a type of cell in the nervous system that have several functions. To date there are five types of glia that scientists have named, they are as follows:

Astrocytes

Microglia

• Astrocytes are star shaped and wrap around the presynaptic terminals of a group of axons who relate functionally.
• Microglia are microscopic in size as their name hints who remove waste material along with viruses, fungi and other microorganisms.
• Oligodendrocytes and Schwann cells are briefly mentioned in the text as cells that aid in the production of the myelin sheath which covers the axons. 



Oligodendrocytes



Radial Glia at work 

• Radial Glia are especially important during embryonic development because they guide the migration of neurons and their systems. After embryonic development they themselves mature into either neurons or other forms of glia. 

In a lecture by Dr. Doug Fields he goes into further detail about the importance of glia cells. What really intrigued me about his lecture is his enthusiasm about the topic. That captured my attention because for the longest time neurologists have thought that the most important part of the brain are the neurons. One of the first things Dr. Fields mentions is that the human brain is 10% to 15% composed of neurons. The remaining percentage is glia.  Now glia are still very new to the field of neurology because there is still so much to be learned about them, mostly due to our inability to study them in the brain. Hopefully as science progresses we will be able to better understand them and their over all importance.

So the idea that we only use 10% of our brains still remains to be refuted and proved. I hope that comes sooner than later. Time only knows how many lives depend on it.