The Workings of Nicotine: Scientific Interplay with Physiological Dependence

Tobacco addiction is best considered a chronic disease, with most smokers requiring repeated interventions over time before achieving permanent abstinence. Nicotine, the major addictive substance in tobacco, activates nicotinic receptors (nAChRs) to initiate a series of adaptive changes at the cellular and circuit levels in brain, particularly the ventral tegmental area (VTA). Disregarding the countless ads and initiatives taken to bringing the detrimental effects of cigarette smoking to light, it may seem not understandable to some as to why certain people are not able to “kick” the habit and put it down for once. Having a father who has smoked since he was 16, I have always wondered if the extent of his addiction to smoking was truly something that could be given up for the sake of his health and others around him. In search for understanding in the addiction of millions over the world, I looked at the scientifically achieved findings of Dr. McGehee along with another supplemental article that slightly correlated with the information he was able to obtain through experimentation.

Interestingly enough, though nicotine has many negative factors, when looking into an article written titled Can Nicotine Be Good for you, it was noted that certain patients had felt as though nicotine presented positive psychiatric effects. Surprisingly, the positively felt affects of nicotine ranged greatly, especially having influence on cognition, mood, attention, and even memory. It was reported that patients with mental disabilities had also taken to smoking at much higher rates, expressing that nicotine had ameliorated certain symptoms.

            Found to correlate in the studies presented forth by University of Chicago’s speaker Daniel S.McGehee at Loyola University’s Neuroscience Seminar on February 23^rd, it was noted that nicotine was able to facilitate long term potentiation in the VTA dopamine neurons by increasing glutamate release via activation of specific terminals, suggesting that nicotine played a strong role in the pre-synaptic contributing in LTP. In his publishing, Nicotine Potentiation of Excitatory Inputs to Ventral Tegmental Area Dopamine Neurons, he further went on the express the much more complex findings of nicotine influence on excitatory synaptic strength. Correlating well with the article mentioned before, the nicotine-induced changes in the VTA were expressed in his findings bringing in light to the brain chemistry of those who rely heavily on the highly induced effects that nicotine brings forth.

With the article I read and Dr. McGehee’s findings presenting a scientific interplay, explaining the chemistry behind the physiological need for nicotine for some, I was able to better understand the daily implications of intake of nicotine that smokers might go through. With increased advancement in looking to mimic or block those regulated excitatory signals put forth by nicotine, the world of health-care has been constantly working towards finding replacements for cigarettes in things like nicotine gum or patches. With continued effort and consideration of findings like these, there is a bright, potential future in alleviating the addictions of smokers, looking to potentially eradicate the detrimental effects.

Article Source: http://www.nytimes.com/2016/03/06/opinion/sunday/can-nicotine-be-good-for-you.html
Speaker Source: Mao, Danyan, Keith Gallagher, and Daniel S. McGehee. “Nicotine Potentiation of Excitatory Inputs to VTA Dopamine Neurons.” The Journal of neuroscience : the official journal of the Society for Neuroscience 31.18 (2011): 6710–6720.PMC. Web. 30 April. 2016
Image Sources: https://static01.nyt.com/images/2016/03/06/opinion/sunday/06fels/06fels-master768.jpg

https://s3.amazonaws.com/lowres.cartoonstock.com/health-beauty-nicotine_patches-smokers-cigarette-craving-crave-forn2203_low.jpg

VENs: A Hidden Gem?

Thomas Edison. Benjamin Franklin. Albert Einstein. These individuals have been categorized as being geniuses. It makes one wonder if there are geniuses lurking among us today. According to some recent studies, a new category of geniuses have emerged: Super-agers. In her presentation, Tamar Gefen spoke at Loyola University Chicago about the research her fellow colleagues and her were conducting regarding Super-agers. Super-agers are individuals who are of at least 80 years of age but, seem to have the memory capacity of individuals between the ages of 50-65.  From an experimental study they conducted, Dr. Gefen mentioned that Super-agers performed substantially better in memory oriented tasks in comparison to individuals who were of the same age group. With the difference in memory performance despite the similar age between the groups, researchers performed MRI studies to determine if differences existed within the brain between the groups. 

Researchers found that in comparison, Super-agers had greater thickness in their anterior cingulate cortex as well displayed a thicker cingulate cortex overall. According to Dr. Gefen, the surprising discovery was that the researchers found that Super-agers had an enormous abundance of VENs, von Economo neurons, within their brains. It has been found that VENs enable the thickness of the cingulate cortex which may give rise to the intellectual superiority of Super-agers.

However, there has been limited research done in regards to the role of VENs within humans. There has been studies done to see if VENs are found in other species. In fact, along with humans, ape species, four cetacean species, African and Indian elephants seem to have VENs as well. When observing the brains of African elephants that were obtained from the Cleveland Metroparks Zoo, it was found that VENs were abundant in their frontoinsular cortex and anterior cingulate cortex.  Researchers found that species with large-brains often had a high concentration of VENs. One plausible explanation is that due to their large size, VENs allow for “rapid transmission of information over long distances”.

Not only are VENs found within species that have large brains but, these species tend to have a high level of intelligence. Thus, is it possible that VENs and intelligence are interlinked? Do Super-agers have exceptional memories due to a high concentration of VENs ? With further investigation on the role of VENs, it is hoped to be able to answer these questions one day.

Works Cited

Picture 1:

https://www.google.com/search?q=superagers&rlz=1C1TSNP_enUS497US497&espv=2&biw=1517&bih=714&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjQtsKs_rTMAhXBUyYKHaPqDloQ_AUIDCgA&dpr=0.9#tbm=isch&q=smart+old+people&imgrc=M1u3u1aDyzAYUM%3A

Picture 2: 

https://www.google.com/search?q=superagers&rlz=1C1TSNP_enUS497US497&espv=2&biw=1517&bih=714&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjQtsKs_rTMAhXBUyYKHaPqDloQ_AUIDCgA&dpr=0.9#tbm=isch&q=african+elephant&imgrc=EdFsv9LYLDmCjM%3A

Article:

http://onlinelibrary.wiley.com/doi/10.1002/ar.20829/pdf

Melody and Memory: How music can induce an emotional response that helps memory formation

Imagine you are driving and get stuck in traffic. You start to feel annoyance with the people around you, regardless of the fact that they have no control of the situation any more than you do. To calm yourself, you turn on the radio and hear a song you can’t recall the name of, but sing along to the words anyways. The words come to you easily, despite not knowing the exact details of the song. This is a form of implicit memory. You can’t recall the exact details, but you can sing the song or at least hum the melody.

            In recent years, the study of implicit memory has come to the forefront, specifically in regards to memory disorders. One form of evidence that implicit memory plays a frequent role in an individual’s recognition memory utilizes the emotional response of the individual. In an article on memory and music, it was theorized that music can act as a therapy for people suffering from dementia. Dementia is a form of memory disorder that varies from individual to individual. It is suggested that music can help memory retrieval and cognition. Implicit memory can be triggered from an emotional tie to a specific song or melody that can trigger a specific memory, which is explicit memory recognition, or can elicit an emotional response. This emotional response is reminiscent of a memory, and it becomes an implicit memory.

            It is also suggested that music can help cognitive functioning as well as memory before and during a memory decline that is onset from dementia. Learning to play an instrument is a good way to help memory formation. This is because learning to play an instrument is a way of acquiring a skill or habit that will form implicit memories since habits and skills do not require conscious awareness.

            The use of music in recognition memory, specifically implicit memory, is a way of emotionally arousing an individual in order to trigger a memory response without conscious awareness. Dr. Ryals of Northwestern University studied the behavioral aspect of implicit memory by using trigger words. These specific words elicit an emotional response that arouses the participant. This triggers implicit memory in a free recall test that uses both emotional and neutral words. His behavioral study examines this idea of variable retrieval, which can also be described as a “tip-of-the-tongue” state. The results of the study suggest that implicit memories, which are also variable retrieval memories, can be triggered when an individual is emotionally aroused.

            Both Dr. Ryal’s study and the article on music and memory suggest similar ideas of implicit memory recognition. Emotional responses and arousals can be used to help individuals who have, or are predisposed to have, dementia or Alzheimer’s disease. By forming more implicit memories, individuals will be able to retain those happy memories and feelings.

http://previews.123rf.com/images/yadvigagr/yadvigagr1211/yadvigagr121100001/16259600-man-silhouette-with-brain-and-heart-Stock-Vector-music.jpg

References

Ryals, A.J., Voss, J.L. The outer limits of implicit memory. (2015). The Wiley Handbook on the Cognitive Neuroscience of Memory. 1. 44-59.

http://www.abc.net.au/radionational/programs/allinthemind/tapping-into-the-connections-between-music-and-the-brain/7288328

Memory Capacity in the Elderly

The article “Morphometric and Histologic Substrates of Cingulate Integrity in Elders with Exceptional Memory Capacity” by Tamar Gefen, Melanie Peterson, Steven T. Papastefan, Adam Martersteck, Kristen Whitney, Alfred Rademaker, Eileen H Bigio, Sandra Weintruab, Emily Rogalski, M.-Marsel Mesulam, and Changiz Geula was used in a talk given by Tamar Gefen. This study focuses on a group of 80 plus individuals that display episodic memory functioning of someone between the ages of 50-65. These unique individuals are referred to as “SuperAgers.” An experiment was conducted with two control groups: middle agers (50-65 years old) and cognitively average elderly (same age as SuperAgers) and one experimental group: SuperAgers. With using the MRI, scientists were able to analysis each individual’s scans and come to certain conclusions about SuperAgers. They found that these individuals displayed the same or greater thickness as the middle-aged control in their anterior cingulate cortex. Compare to the cognitively average elders, the SuperAgers also displayed a thicker cingulate cortex. They also found that SuperAgers had an abundance of VENs, which enhance the thickness of the cingulate cortex. Scientists came to the conclusion that this thickness may contribute to the preservation of cognitive and intellectual functioning in individuals who are 80 years or older in age. These findings lead scientists to believe that there could be possible biological factors to resistance for age-related diseases.

            The article, “Forget about Forgetting: Elderly know more, use it better” from Science Daily also focused on memory capacity in the elderly. This article believes that older people are slower because they retain a lot more information compared to younger people. They used the example of a computer database; if you keep adding more and more files to a database, the slower the computer will work. Similarly, if an elderly person cannot remember someone’s name, it might have to do with the fact that in the past couple of decades there have been more diverse names. Therefore, since there has been a remarkable increase in the number of names used, there are significantly more names for the elderly to remember. Even a computer would have a difficult time locating a name in today’s time with the increasing diversity and number of people. To support this claim that the elderly are slow because of the amount of information they have acquired over their lifetime, scientists performed a “paired-associate learning” test. They compared results from younger people to the elderly and found that the elderly took longer because they were sorting through what is a nonsense pair and what pairs connected whereas younger counterparts were not able to do this. This proves that older people are not weak or slow but actually know more than we think.

            Both of the articles discussed, “Morphometric and HIstologic Substrates of Cingulate Integrity in Elders with Exceptional Memory Capacity” and “Forget about Forgetting: Elderly know more, use it better” explore memory capacity in different ways. Gefen believes there is a biological reasoning for why some older people have excellent memory. Her research focused on how the anterior cingulated gyrus thickness and VENs contributes to the memory of the elderly. On the other hand, the article from Science Daily took a less biological approach. They believed that age does not mean one’s memory is weak, but rather they are slower because they have acquired so much information over the span of their lives. Even though both articles view memory capacity in the elderly in different ways, they both contribute to the overall progression to understand how the human brain functions as people age.
https://www.sciencedaily.com/releases/2014/01/140120090415.htm
http://i.huffpost.com/gen/1740227/thumbs/o-FRUSTRATED-OLDER-PERSON-facebook.jpg

Memory- so complicated to memorize

         Memorize. Remember This. Be aware of this. As college students, we have all heard these phrases right before exams. But what exactly is memory? As Professor Ryals explained in his recent presentation “The Continuum of Awareness in Recognition Memory,” memory could be more complex than we thought. Rather than the two categories explicit and implicit Memory, Professor Ryals explained that memory could be on a continuum.

Professor Ryals explained that there are two distinct states of recognition and how it may not only be under explicit memory. The two states of recognition are recollection (all-or-none) or familiarity (variable). All-or none recognition would be when you see a picture of a celebrity and remember their name right away. A variable recognition would be when you would remember facts about the celebrity but you would not be able to remember this celebrity. Variable recognition oftens leads us to complete recognition. This leads to the idea that recognition must be open to conscious awareness. Unlike recollection retrieval, variable retrieval is enhanced by arousal and valence. The data also showed that implicit and explicit memory may co-occur and it may just depend on what kind of tests you’re doing. Professor Ryals pointed out that flexible assumptions and new tests need to be made to advance his theory of memory being on a continuum.

What interested me the most about the talk was the application aspects that Professor Ryals discussed. There is more research showing how there may be memory impairment in breast cancer survivors. The term for it is “chemofog” or “chemobrain.” This post cancer impairment may be due to the MTL toxicity and the stress that comes with the treatments. Studies showed negative brain activity in the hippocampus and a shrinkage of the hippocampus. Professor Ryals gave us the final question: can we prevent this?

After the talk, I came across the article, “Stress and Memory Problems in Breast Cancer Patients.” It was written by Stacy Simon and it talked about the “Chemo brain” that Professor Ryals ended his talk with. However, rather than focusing on the chemical aspects, Simon focuses on how stress can also play a huge factor with memory.

Stacy Simon argued that stress can act in two ways. The first way is cognitive. People spend a specific amount of energy when making decisions, paying attention and controlling emotions. When having to make decisions on diagnoses, many people are left with no more energy for other cognitive functions. This would result in a loss of memory. The second role is more a physiological role stress takes on the body. With added stress, there is an increase in the hormone cortisol. Cortisol reduces the ability to think or retrieve long-term memories.

Simon points out that rather than just focusing on chemotherapy, cancer patients should reduce their stress levels to effectively make the most of the treatment given to them. Some preventive measures were doing regular exercise, yoga, and socializing with someone. Even with chemotherapy, Simon points out that what is important is the quality of life afterward. By learning how to reduce stress, this will strengthen the individual cognitively.

I thought it was interesting how memory, which is still being studied extensively by researchers like Professor Ryals, can be easily affected by factors such as chemicals and stress and make it such a complicated concept to study. So as I start preparing for finals, I’ll prepare for the mini breaks needed in between to de-stress and make my memory as sharp as it can be!

Simon, Stacy. "Stress and Memory Problems in Breast Cancer Patients." Stress and Memory Problems in Breast Cancer Patients. N.p., n.d. Web. 24 Apr. 2016.

Ryals, Anthony. “The Continuum of Awareness in Recognition Memory.” Loyola University Chicago. Cuneo 109, Chicago. 12 April. 2016. Lecture

Foods Impact our Decisions!

            By Sukhbir Thind

Have you ever thought about how fast food is affecting your decisions and your productivity! Making decisions between desert and a healthy snack may be really hard, but one needs to understand that food affects our productivity and the way we make our decisions.

Recent studies at California Institute of Technology suggest that when we make decisions especially when it comes to food choices, self-control plays a huge factor. Self-control depends mostly on how our brain incorporates the taste and health related factors. Cal Tech wanted to design an experiment that integrates taste and when taste affects our choices. Dr. Sullivan used 28 students and asked them to fast for four hours. Once these students had fasted for four hours they were asked to rate 160 different foods on a scale from -2 to 2. The rates were based in 3 factors, healthfulness, tastiness and the participants’ desires to eat it after their long hours of fasting.

Afterwards the participants had to pick which food to eat from a pairing system that paired 280 random pictures of the same food. The experimenters used a new technique that analyzed how the mouse cursor moved. So a participant can move their curser to an unhealthy food and then reconsider to a healthy food and click on that or vice versa. Cal Tech did this to understand and analyze the decision making process and time it takes for one to choose between taste and healthfulness, and which factor dominates the decision. According to their research people first choose taste over healthiness. The time it took for high self controlled participant to choose healthy was 200 milliseconds. The time it took for low self controlled participants to choose health was 323 milliseconds.

 

From this experiment, they also observed that if one can see the number calories enlarged on the label and see how much fat is in the food, they are less likely to eat it. Decisions are based on visuals as well as taste.

This relates to Brain Sweis’s presentation at Loyola University of Chicago. Sweis is a medical student who is performing a study that involved decision-making and relates it to food choices and time. He used rats for his experiment to see if time plays a big role in their decision making for food choices or if food’s taste plays a bigger role even if the rat has to wait a long time. In this study, rats were given pellets that had a flavor of bananas, chocolate, and many other different fruits. The rat had to choose its path to go to the flavor, but there was a delay each time before the rat received the flavor. Some rats waited the extended delays for their flavor and some rats just skipped the long wait and moved on to other short delayed flavors. Some rats faced regret when they had to skip their favorite flavor and this regret is what caused the rats to wait at other stations even if the wait was longer for the flavor. This experiment helped one consider how time can play as an important factor in decision-making as well as the flavor or taste of the food. The more tastier the food, the more rats wanted the flavor and the longer they were willing to wait.

Now how do these two relate? When picking food, time and tastefulness play an important role over healthfulness for most people. Time plays an important factor when we are making a decision. When some people are busy and can’t prepare healthy foods, they buy fast foods.  They do not want to wait to make food and rather will take what comes more “easily” to them. People ignore the fact about fast foods and desserts being unhealthy. Later these decision come back to haunt them with health related issues. Another factor is desire, when one desires the food they are willing to do anything for it. This is a sad reality that people will do anything for the unhealthy foods at fast foods rather than eat the healthy vegetables that they can prepare at home because fast foods “taste” better. Just as the research at Cal Tech suggested that people moved their cursors to the unhealthy but then reconsidered before they clicked the unhealthy food. Taste dominated healthfulness. Cal Tech says that before one eats an unhealthy snack, they should be reminded of the calories and fats that are in the foods they are about to consume, so they can realize that unhealthy calories will affect them in the future. Visuals and enlarged labels can play a big role in preventing people to buy heavily contained calorie food.

So next time you stop at a fast food restaurant because you “want” fries and a burger, think about all the fats and oils that food has. Then evaluate all the healthy options you can make at home from a homemade burger to a fresh Cesar salad. Choices and decisions are important, but more importantly, making the right ones are the key to success.

References:

Article 1.

http://www.huffingtonpost.com/2014/12/17/the-best-time-of-day-for-_n_6334310.html

Image 1-http://cdn.shopify.com/s/files/1/0260/2057/files/boy-making-choice-decision.jpg?7942556593889947105

Image 2- http://www.wired.com/wp-content/uploads/2014/06/RRow.jpg

Image 3- https://static01.nyt.com/images/2011/01/25/business/Label1/Label1-articleLarge.jpg

Image 4- http://exposure-communications.com/wp-content/uploads/2015/03/foodforthought.jpg