Neurochemistry has been a class I have feared since being a first-semester freshman. I struggled in Gen. Chemistry and Organic Chemistry. I started to find a liking for the subject when in Biochemistry, but I was still hesitant about this course.
Walk into first day of class and am greeted by faces I have grown with over the past three years and have considered to be my friends since Intro to Neuro freshman year. I am normally an uncomfortable person in regard to conversation-based courses, however, having a group that you already know really helps. This allowed me to communicate with peers openly and comfortably about heavy neuroscience topics. Also, this group allowed for a safe space during discussion days where individuals felt comfortable to share more personal stories that related to the topics at hand.
For the first six classes, we reviewed basic signaling molecules and pathways to refresh our brains and set us up for the rest of the weekly topics. For the first class, we examined excitatory signaling that is capable of stimulating an activity and/or response by a neuron. The primary excitatory neurotransmitter being glutamate with the primary receptors being NMDA, AMPA and Kainite. Then we discussed inhibitory and retrograde signaling with GABA being the primary inhibitory neurotransmitter. These receptors include ionotropic GABA-alpha and metabotropic GABA-beta. Glutamate and GABA work together to modulate immune and endocrine system responses.
Following the basic signaling molecules, we began looking into G-protein signaling and G-protein coupled receptors (GPCRs). Gi and Gs receptors help to regulate adenyl cyclase activity, whereas Gq helps to regulate movement of Ca2+ ions and PKC. These receptors are characterized by a seven-transmembrane alpha-helical fold. Following GPCRs we talked about RTK pathways. These pathways include insulin pathways and use tyrosine kinase activity. Then, with cytokine pathways we discussed the Jak/Stat pathway. These pathways can include autocrine, or activation of cell itself, paracrine, or signal activates nearby cell, and endocrine, or activation by signal in circulation that activates a cell further down. Lastly, we talked about wnt-b catenin signaling. This pathway regulates cell fate and stem cell differentiation during embryonic development.
The first six topics helped to solidify information that has been drilled into our brains for many classes. Coming from a semester that felt as though I retained nothing, it really helped to have a refresher and get me back on track with basic signaling. I tend to gravitate towards the psychological and neurobiological aspects of my major, but this class help to confront the parts of neuroscience that I have avoided for some time.
The first topic we discussed included making memories of stressful events. In this we discussed how stress effects memory retention. In particular, I looked into adjustment disorder, acute stress disorder, and PTSD. Adjustment disorders causes distress out of proportion to the event with behavioral and emotional within three months of the event. Acute stress disorder is any maladaptive response to a traumatic event with symptoms lasting three days to one month. Symptoms can include dissociative behaviors, steep disturbances, and severe anxiety. If symptoms persist past one month, the diagnosis changes to PTSD. This topic allowed me to connect information I had learned about symptoms in abnormal psychology to the neurochemistry in stressful events.
The next topic talked about was mental illness, specifically the role of wnt and GSK3 signaling in schizophrenia. Since schizophrenia is believed to be due to a lack of b-catenin transcription, overactive GSK3-beta, and an increase in dopamine, hallucinations are believed to be one of the most apparent symptoms of the disorder. Hallucinogens that bind to 5-HT2A receptors. Antipsychotics bind to specific serotonin receptors in the VTA and ventral striatum, this may be the area for psychosis. Since hallucinogens are able to evoke hallucinations that are easily to distinguish as fake, but hallucinations from psychosis evoke stimuli that appear real.
We talked about addiction and the cellular basis for it during for the third topic. For this week, I took time to look at the dual diagnosis between mental illness and substance use disorders. ¼ to ½ of all substance abusers also meet the criteria of a mental illness or have a diagnosis of a mental illness. The most common comorbidities including ADHD, depression, bipolar disorder, and schizophrenia.
For the fourth week, we talked about the metabolic cascade that follows a concussion. Though bilingualism is meant to be beneficial if taught during the “critical period” of neurodevelopment during childhood. During the critical period, children are able to gain a logical and emotional connection to the language being taught, whereas adults learn mostly from a logical standpoint. With higher executive functioning seen in bilinguals, following a mTBI the individual may suffer from a disproportionate return of language. Also, children have less myelin protecting axons, children are more likely to suffer axonal injury and executive function deficits. Even after learning about all of this, I managed to sustain a concussion myself and was able to use the SCAT-5 to go about making sure I do not impair my brain farther than I already had.
The fifth week we discussed the connection between Alzheimer’s and diabetes. Also, this topic was returned during the seventh week when discussing hypothalamic inflammation and obesity. Hypothalamic inflammation can result from poor diet and health. This continuation of inflammation in the brain can lead to innumerable complications, one potential complication is the increased risk for Alzheimer’s. Though Alzheimer’s can be hereditary, through the APOE-4 gene, if diet is not maintained, if the brain is not protected from injury, you are going to be at an increased risk no matter your family history.
During the sixth week, we discussed autism spectrum disorders. Now I am passionate about this topic and was very excited about this week. I discussed the benefit of sensory rooms in schools, but also the potential downfall of excluding children from mainstream rooms. I will say I was disappointed in some of my peers from their lack of awareness on some aspects of ASD and laws that protect vulnerable adults. It helped me to stand up later on in another one of my classes for something that was said that didn’t directly affect me, but I imagined it being said to one of my kiddos from work and was heartbroken.
During the eighth week, we discussed how the endocannabinoid receptors work on the CNS. This week I looked at if targeting the endocannabinoid system could help reduce the aggregates seen in Huntington’s Disease. ERK has to be phosphorylated to see any positive effect, but activation of CB1 receptors did allow for cell to be rescued from cell death. However, this also increased the total number of aggregates being produced.
Lastly, we discussed how music affects our brains neurochemically. For this week, I chose to look at if the genres we dislike changes how the neurochemistry plays out. It turns out that even if we hate a genre, our brain will still release dopamine and trigger the amygdala to evoke emotion.
Mainly, in all of these topics I was able to make a connection to psychology courses. By examining neurochemical changes in the brain, it helps make sense of why certain symptoms are present, thus allowing to make sense for different therapeutics that are being used to treat a variety of disorders. This class helped me to become more confident in my abilities to communicate with peers about topics and inform them on other topics. This skill will be heavily transferable as I progress beyond Concordia. Discussion days really helped to make us feel as professionals and not just students. Also, even if we were all in a neurochemistry course together, we all come from different majors, have different life experiences, and interpret information differently. This is one of the cool things about a liberal arts education. We get to dive into and inspect a topic from a variety of disciplines and potentially gather a deeper understanding than a neuroscience-only education.
Photo Sourced From: https://www.brandeis.edu/psychology/neurochemistry-cognition/
