Depression - All Time Low

Depression is something that has become all too familiar and most common. Only recently has it been really taken seriously to be studied. Especially with students in colleges and Universities, you hear of the pressure needed to maintain a certain level expectation, which if it isn’t met, then they are deemed incapable. On another note, there is the most commonly media and peer pressure of the fear of being left out or not appreciated. People start losing themselves and end up in this cyclic destruction. Once you are in this cycle it is very hard to get out and outside influences can do a lot to a person with depression.

In  a recent study done by Dr. Rebecca Stilton, a professor and researcher at Loyola University of Chicago looks at how positive affect is related to depression. Dr. Stilton starts off by defining depression as having anhedonia; which is the reduction in ability to experience pleasure in daily life experiences. Anhedonia is specifically correlated to have low positive affect and high negative affect. Dr. Stilton makes sure to emphasize how having low positive affect is what really matters because of it direct relation with depression. It cannot be negative affect since it could be related to both depression and anxiety. According Dr. Stilton, one is considered to have depression if they have at least five out of nine possible symptoms in order to be fully diagnosed with this. In her experiment, the participants were of two types. Some participants did not have any history of depression and some participants had remitted depression, meaning they experienced future depressive episodes. Dr. Stilton, as a way of indicating future depressive episodes, she measured alpha wavelength activity in the left prefrontal cortex using EEG. After her experiment, her results showed that high levels of alpha wavelengths were associated when there was low positive affect. In other words, high levels of alpha can possibly be an indicator of future depressive episodes.

Interestingly I came across an article, Can Mushrooms Treat Depression? Which caught my attention mostly for its unique title and grew a curiosity of my own. The article starts off with a personal anecdote of how one ate Mushrooms and felt like they were in a better mood. It goes on to explain how depression is caused and what it entails; meaning there is a negative feeling and there is a low positivity in general. The article also mentions how there have actually been studies done on why this is the case. Mushrooms contain Psilocybin, which resembles the structure of serotonin. Serotonin is a neurotransmitter that regulates mood, appetite, sleep, cognitive functions like memory and learning and feelings of pleasure. Psilocybin may actually stimulate serotonin and serotonin receptors in the brain which causes the pleasant mood after eating mushrooms. Researchers concluded that psilocybin might be useful in psychotherapy as an adjunct therapy to help patients reverse “negative cognitive biases”; which is all too common in people with depression, where the person recounts negative memories versus positive memories.

It was interesting to see how closely both studies mentioned one way or another how depression is a form of having high levels of negative affect and low levels of positive affect. However, Dr. Stilton focuses more on what may cause future depressive episodes and how that is linked to the alpha wavelengths in the prefrontal cortex. Whereas in the article, it talked about the possible option of what can cure or help people diagnosed with depression to get out of this cycle of running negative thoughts. The two articles reaffirmed that in order to have or prevent depression, there needs to be a level of positive affect that must be maintained. Once the negative affect starts taking control, the individual can be thrown into depression and if it continues, then could have future depressive episodes.

References

Silton, L. R., Polnaszek, K. L., Dickson, A. D, Miller, A. G., Heller, W. Low positive affect is associated with reduced prefrontal cortical activity in remitted depression. Psychophysiology, 1-31.

Bone, Eugenia. "Can Mushrooms Treat Depression." NewYork Times: Sunday Review. 29 Nov. 2014. Web. 04 May 2016. <http://www.nytimes.com/2014/11/30/opinion/sunday/can-mushrooms-treat-depression.html>.

SuperAgers have SuperBrains

            There is no denying that with aging comes a decline in memory and cognitive function. Unfortunately it is an inevitable aspect to growing old. Not all hope is lost though! Just take a look at SuperAgers. These are a group of elderly adults 80 years and older with memory capabilities as a strong as healthy 50 to 70 year olds! What is it though that gives these SuperAgers such efficient aging? Scientists have been questioning this and have made some remarkable findings.

            Lars Nyberg and colleagues from Umea University in Sweden claim that it is what you do at old age which ultimately dictates how one ages. According to the Science daily article, “Maintain your brain: the secrets to aging success,” “engagement is the secret to success. Those who are socially, mentally and physically stimulated reliably show greater cognitive performance with a brain that appears younger than its years.” Nyberg continues to state that staying physically and mentally active is a way to maintaining a healthy brain in aging.

            So can one simply train their brain in old age to keep it healthy? Gefen et al. from Northwestern University have research on these mystifying SuperAgers. They discovered that SuperAgers actually have a much thicker dorsal anterior cingulate cortex (ACC) – a part of the brain important for many cognitive functions. They also noticed that SuperAgers had a much larger ratio of specifically von Economo sensory neurons in the dorsal ACC.

            This leads me to question of how do these SuperAgers gain their super memory powers? That is, how do they have such thicker dorsal ACCs. Looking at the research from Nyberg et al., one could predict that exercising your brain at old age could be the reason for the thicker brain region in SuperAgers. If this is the case, an explanation can finally be given to how to retain strong memory abilities at old age!

Multitasking, Hypocrisy at its Best

Multitasking, Hypocrisy at its Best

In “The Outer Limits of Implicit Memory” by Anthony J. Ryals and Joel L. Voss, implicit memory is examined through a new lens, having a much greater depth and offering new implications that could help with understanding this complex mystery we refer to as memory. Examining the different types of memory and how they are interrelated are crucial to understanding how we can most effectively utilize our memory in our daily lives. While there are four main misconceptions the reading addresses, I found the last belief, the one about how implicit memory was traditionally believed to be involved in only the specific brain regions that are entirely distinct from explicit memory, to be particularly interesting (Ryals & Voss, 2015).

In the reading, Ryals and Voss explain the limitation that lies in the fourth belief. They point out that while there are many studies that help to clearly distinguish between the two types of memory, implicit and explicit, there are have rarely been any studies to search for any connections that may link the two in the neuroanatomy (Ryals &Voss, 2015). Thus, they have examined of the main regions dealing with explicit memory and have suggested potential connections of those regions with implicit memory as well. The first region they looked at was the hippocampus. The hippocampus, one of the key players for explicit memory, through recent findings, has shown that it may be more connected to the networks of implicit memory than previously thought. For example, the reading notes how the hippocampus may play a role in “implicitly biasing decisions” and that by destroying the hippocampus and the MTL around it, one can also see measurable effects in implicit memory such as through “eye movements” (Ryals & Voss, 2015).

The second region the authors highlight is the prefrontal cortex. This region has been recognized for its function in “explicit recollective memory” and has been thought to happen via with a sense of awareness. However, some of the more newer studies have demonstrated that not all of the “prefrontal executive functions” may need awareness in order to occur (Ryals & Voss, 2015). For example, it was demonstrated through a study that people were sometimes able to “backtrack” in order to help with their memorization of objects and what was more profound was that the individuals were unaware of the fact that they were backtracking, suggesting that this hippocampal-prefrontal activity may not have needed awareness.

Therefore, from this examination of the hippocampal and prefrontal cortex, it may be necessary to assume that there may be many more connections between the regions of the brain that work with explicit and implicit memory than we thought previously.

That being said, when during his speech, Dr. Anthony J. Ryals elaborated on the method used to determine how implicit memory and a lack of awareness could be tracked or measured through eye movement. He explained how the eyes are crucial to understanding implicit hippocampal functioning through the use of an eye tracking device. To examine this implicit recognition, the research team created an exploration profile in order to track the fixations that occurred. The degree to which the eye overlap discriminated similar from non-similar and had higher hits and less misses showed correlated to the amount of function that could occur without awareness. Thus, the more eye overlap, the more hippocampal activity that was functioning without awareness. This type of activity, however, only seemed to appear in the right lobe whereas function with awareness occurs in both lobes. Dr. Ryals reported that the overall results of the study were not very definitive because across the memory performance, most of the participants were right around chance performances. However, he did still assert that despite the chance-level behavioral responses, eye movement is important in understanding implicit processing without many of the implications seen in earlier ways of studying the topic.

To explore the actual implications of what this connection between regions working for explicit memory and implicit memory, I read Daniel J. Levitin’s article, “Why the modern world is bad for your brain.” The article was an interesting read in that it argued that while people today believe that multitasking helps them become more efficient with what they do, finish things in half the time, and ultimately, accomplish more than they thought possible, in reality, multitasking actually does more harm than good. Levitin discusses how the human brain is not meant to carry out this overwhelming amount of tasks at one time, thus, instead of providing benefits, it provides more cognitive costs if anything. He claims that multitasking actually increases the amount of stress hormone, cortisol, as well as adrenaline that often creates mental blocks and can overwhelm the brain (Levitin). Additionally, he says that the implications on the prefrontal cortex and the hippocampus are significant. With the prefrontal cortex, because it has a “novelty bias”, it is “easily hijacked” by new objects and subjects, thus, through multitasking, it becomes distracted very easily which is not beneficial to humans since this region is supposed to maintain our focus during tasks. Moreover, when looking at the hippocampus, Levitin explains that when we are learning new information and trying to store it in our memory, because of the multitasking, the new information goes not to the hippocampus, but goes to the striatum. This change can make in increasingly difficult for people to retrieve information more efficiently since the striatum isn’t necessarily designed for facts or ideas, but rather “procedures and skills” whereas the hippocampus is the necessary component to organizing information in ways that make retrieval easier (Levitin).

Referring back to Dr. Ryal’s research with the information from the article, if the hippocampus and the prefrontal cortex are both interconnected with explicit and implicit memory function, then it would be important to consider if this multitasking irony will have an effect on both types of memory. The presentation of the information in this article may imply that multitasking could have a heavy implication on the formation, storage, and retrieval processing systems of both types of memory because in the case of the hippocampus, if the information is actually going a different route and into the striatum instead of the hippocampus, then it may be possible to assume that neither of the memory processing systems are able to function correctly.

Works Cited

Digital image. Multi-tasking: The Art of Messing Several Things up at Once. Hippocampus.co.za, n.d. Web. 4 May 2016. <http://hippocampus.co.za/multi-tasking-the-art-of-messing-several-things-up-at-once/>.

Levitin, Daniel J. "Why the Modern World Is Bad for Your Brain." The Guardian. Guardian News and Media, 18 Jan. 2015. Web. 05 May 2016. <https://www.theguardian.com/science/2015/jan/18/modern-world-bad-for-brain-daniel-j-levitin-organized-mind-information-overload>.

Ryals, Anthony J., and Joel L. Voss. "The Outer Limits of Implicit Memory." Neuroscience Seminar Box. N.p., n.d. Web. 4 May 2016. <https://luc.app.box.com/v/neuroscienceseminar/1/5783523437/50496532121/1>.