Curated Paper 2 - KP

Starting off with brain research I decided to watch the video that was given to us. I know our brain is divided into two halves and that it's super wrinkly. It’s cool that the brain differs between everyone, each with its own experiences and memories inside. When I was a junior in high school, I decided to take an anatomy class. I didn’t really know what I wanted to do with my life at that point but figured it wouldn’t hurt to try something new. I fell in love with the class and was invited to go stay up at Utah University for a medical camp. While I was there I learned a lot of things but one of the days totally changed my life. I got to hold a real human brain. They asked if I was comfortable with it of course but how could I say no? I held the brain and I’ve never felt so much wonder within myself since that day. To think an entire person is inside of there, all of their insecurities, their thoughts, regrets, happy moments, all bundled up in one little organ was seriously the most amazing thing I have ever seen in my life. This experience brought me to love anatomy and learning about the brain and all of its crazy functions. Anyway, back to the video. The brain is separated into four lobes each lobe containing its own areas that function differently from others.

The first lobe is the frontal lobe, it covers problem solving, intellectual activities, as well as attention and a few other things. The second lobe is the parietal lobe, it covers pain reception, visual functions, and some other things. The temporal lobe covers visual and auditory memory (helpful that it’s right by the ears as well). The last lobe is the occipital lobe, it helps with recognizing colors, words and movement. The cerebellum is technically part of the brain and helps with balance, posture, and coordination. Hearing about these parts of the brain reminded me of a topic I discussed in a psychology class about the amygdala of the brain where people who had committed crimes often had less function in their amygdala than normal. So this got me wondering if I could find the study we discussed in that class.

I straight up searched “low amygdala activity” and I found a pretty good one that talks about the amygdala activity. It was a study done to basically figure out if the amygdala does work during hard thinking. They saw images and had to push a button when another image came up that was identical to the one they were supposed to remember. They did find that it was connected and that a significant moderation effect was found in the left amygdala. Although it isn’t quite what I discussed in high school, it is really cool to see what other effects the amygdala might have on everyday life. This got me thinking about other imbalances in the brain so I decided to look that up next.

I ultimately decided on depression because that’s what came up the most when looking up chemical imbalances inside of the brain. In this study they took ninety undergraduate students and basically took a three part questionnaire that asked about their treatment, their demographic and history of mental health problems. The questions also had a text before or after about how depression is a common imbalance in the brain. This study covered more of what they felt about these sayings rather than the actual chemical imbalance they have. Regardless, it is still interesting to see how they feel about these types of statements. In the study it says that individuals who endorse a chemical imbalance explanation might have more favorable perceptions of depression itself and treatment. This is very interesting to me because most of the time when someone is told there is an imbalance of some sort it comes out as rude to them and they take it in the wrong way. Seeing here that some people feel more comfortable with that definition is really cool to see. This also got me thinking about drugs and their effect on the brain. I started my research by hopping into google scholar (like usual) and looking up How drugs affect neural pathways. I found one about addiction and decided to read it.

This paper first starts talking about cocaine and other drugs and how they somehow promote addictive behaviors for the drug. It states that cocaine and amphetamines enter the brain and mess up the function of cell membrane transporters. The interference makes a fast rise of dopamine levels that result in psychomotor stimulation; being high. It is still a mystery though of how these drugs induce a compulsive pattern of seeking and taking. It also mentions that some drug addicts are vulnerable for many years to relapse and cravings. A really interesting thing it mentioned was also that animal studies suggest that the progression from initial dosage to addiction is from habit-based learning. These parallels are found between the signal transduction cascades and molecular adaptations associated with both processes. This big chunk of information is followed by the fact that regular dosage of amphetamine or cocaine actually changes the morphology of dendritic spines in regions of the brain that are related to addiction. These same areas are also thought to be related to learning. That’s literally crazy. This got me thinking about addiction that I’ve seen in my life. Mild addictions to addiction that has taken life. I’ll only mention the mild as it connects better with habit related learning.

Throughout my life I have had many family members who liked to smoke cigarettes. I would stay over at my aunt’s house and she would smoke about every hour (always outside when we were there though). It was a little confusing to me when I was younger because I didn’t get why she would go outside no matter what activity we were doing (we did TONS of arts and crafts at her house). But knowing what I know now, I know how it feels to almost instinctively move towards something. I’ve also seen a different aunt of mine with her smoking endeavors. She smokes occasionally here and there but no matter what will smoke before she goes to bed and right after she wakes up. It’s the same interesting routine that makes me think about learned behaviors. When thinking in a classroom setting sometimes professors will say “Get into a routine of studying and you will do better in my class” This sense of routine is crucial in some people’s lives and breaking that routine can throw off their entire day and mood.

Anyway enough yapping let’s get back to what the paper says about neural pathway changes. The paper mentions Long term potentiation (LTP) . I want to take a quick detour and cover what that is because I really have no idea. So I just looked that up and found that it is the long-lasting change in output response to transient input. What the heck is transient input you ask? No idea, let’s find out. Transient input is the signal your brain sends when remembering a memory or learning something new. It’s like little pulses of electricity running down your neurons, really cool!

Taking drugs alters another thing called the accumbens, this structure acts like a middle man for the limbic and motor systems. The drugs are altering the connection between them so that they exhibit more drug-seeking behavior. It mentions that plasticity can underlie addiction because of its signals through glutamate. Glutamate is a key neurotransmitter in maintaining neuroplasticity which is important for the formation of certain neural pathways. The change to the accumbens mentioned above is a change in the glutamate transmission within it. It mentions how the drugs interact with the dopamine transporter itself and mess up the process of its removal as well as have a longer, more unregulated, dopamine release. 

This got me curious if the synaptic cleft can be damaged. From what I found it’s really only injury and inflammation but I want to know if there is anything that can irreversibly bind to the synaptic cleft. The information I got on a paper was that certain toxins bind themselves to the neurotransmitter itself and not necessarily the synaptic cleft which was pretty cool to see. I still wonder if there are things that can bind in the cleft but I’m not looking up the right things.

Anywho, LTP and LTD are important in creating new pathways of learning and are actually generated by projections from the prefrontal cortex. This connection of these pathways is thought to be the reason that addiction becomes a behavior. Behavior is a large part of becoming addicted to something and it’s very interesting to me that it alters behavior so dramatically and so quickly in some cases. This behavior (mostly observed in rodents) is also called sensitization, the models made from this are observed to be very useful in the study of human behaviors as well. It is so amazing that drugs themselves can disrupt the neurons and reroute our way of thinking. There is also a theory that there are feelings of liking and wanting that are produced normally while the wanting is what is altered and intensified with continued drug use/exposure. It also mentions that the amygdala might also participate in the process of sensitization. This interests me greatly. As I mentioned before, damage or low development of the amygdala can produce individuals who are more likely to break the law in serious ways. Murderers were my example above and although I couldn’t find anything about them, I do remember the amygdala having a key role in their studies.

Overall, the papers I have been referencing were actually so amazing and had such good details that I loved reading about. The brain has so many functions that we know and so many more that we have no idea about. It truly is amazing to see the different processes that can be observed just by introducing drugs into the brain. Although it may be a little cruel, we would never know these things if we had never dared try them. Addiction is also a very interesting topic to me because I have so many relatives who struggle with it. Seeing how the drugs themselves alter the pathways in our brains and how that can even change the way we think is so incredible to me. The neurons that bind our very beings are so fragile and interchangeable it really is incredible to think about. I could really go on and on about the nervous system because it really is such a fascinating subject, the unknowns involved are very intriguing and I hope to learn more and more about drugs and their effects on the body and mind.