Effects of Spaced learning on Memory Encoding and Retrieval

 

Throughout the development of students from their youth until young adulthood, and beyond, our institutions strive to teach us concepts and basic courses to aid in critical thinking and problem solving that is crucial when navigating life. While every student can excel in their favorite subjects, it is important to know how the learning is done. Certain learning styles that work for students in a subject they have a high affinity for will not work for other, more challenging courses that require more time and effort, regardless of student preference. Because Western education strives on test-taking systems and point averages to quantify the amount of learning an individual student has done, learning has become an interwoven memory as it is needed to remember key concepts to use in applied questions or recall facts. While one would think seeing information in large and concentrated blocks, researchers at York University in Toronto found that smaller and more spaced-out blocks of studying are much more effective at allowing the brain to retrieve newly learned information and remember what was just learned.

In further detail, the students who participated in the York University spaced learning experiment were asked to attend a meteorology lecture for 45 minutes. While the control group took an online quiz the day after the lecture, the experimental group took the same quiz eight days later. The two other factors in the quiz were the complexity of questions: out of the 40-question quiz, 20 were factual, where a recall of information was necessary, and the other 20 were applied questions that required the recall of concepts and successful application. Five weeks after the quiz, and at the end of the experiment, both groups took a final test where the experimental group did significantly better. More specifically, they performed a half-letter grade better than the control group in absolute performance: both in applied and factual questions.   

While no shocks were administered to the students taking the exams, learning, and memory play a critical role in the hippocampus. In Dr. Grella’s experiment, the emotions connected to hippocampus-mediated memories were altered by inducing a shock on mice who had their dentate gyrus tagged by a mix of viral components. After shock-based conditioning, the mice’s memory of their environment where they experienced the jolt elicited a learned fear response in behavior, as shown in the reactivation of the ventral dentate gyrus after tagging from the viruses. Furthermore, in different environments, the fear-based behavior of freezing was reduced to that of anxiety-like actions. This suggestion is also found in learning processes much like that of spatial learning: the location where information is processed and encoded in memory will aid in its recall. Furthermore, the more associations that are made to the memory, such as different spaces and emotional states of the individual forming the memory, the stronger and quicker it can be recalled.  Even though behavior is unaffected by this, it is a contributing factor to the informal theory of spacing effect learning.  

Conclusion: In conclusion, through observations done by test-based studies like that of the York University staff and the more in-depth experiments with mice and dentate gyrus pathways done by Dr. Grella, how fast learning and memory can be encoded and processed rely on several different factors.

 

References:

https://www.sciencedirect.com/science/article/pii/S0959475214001042?via%3Dihub

https://www.brainfacts.org/thinking-sensing-and-behaving/learning-and-memory/2021/the-neuroscience-behind-the-spacing-effect-030421

Progesterone and the role it can play in Myelination-Peyton Daly

Progesterone, a female hormone that is primarily used in reproductive health, has undergone a drastic change in the world of research. For a period of time, sex hormones were only believed to function in the scope of reproduction and sexual health, with possible implications on how humans develop in the womb. However, further research has suggested that other implications, specifically those in the neurobiological functions, of both women and men could exist. The focus of these studies in neurobiology link progesterone and other steroids to multiple factors in how humans function, but a sub-section of this research is dedicated to its role in myelination. Myelination is the process of lining an axon of a neuron with a protective coating made to provide support, protection from any damage that may occur to the neuron and, most importantly, allow insulation on the axon to allow electrical signaling to become quicker. However, because of its location on the axon of the neuron, it provides easier access to damage from neurological disorders. This damage can also spread to the neuron itself, making it difficult for regeneration. However, progesterone has played a key role in understanding not only the mechanisms of myelinating, but also the process of repairing the damage to myelin sheaths itself for disorders like multiple sclerosis.  

In research done by Dr. Abdel Mouman Ghoumari from the University of Paris-Sud, the neurological aspects of progesterone are observed, specifically their effect on myelination and myelin repair in the brain. The process of myelination allows electrical signals from other neurons to travel quicker in the brain and communication between major neurons to become more efficient. Dr. Ghoumari uses the method of cryolesion to isolate sciatic nerves in mice, which keeps the basal lamina tubes intact to support regeneration. A week is given to allow regeneration, and after this week is completed, progesterone was injected to these sites. During this week period however, the myelin sheaths had only reached about 1/3 of the typical size required to provided adequate insulation. The injection of this progesterone (100 micrograms locally) showed an increase in the production of remyelination of axons. The evidence of this study, as well as the meta-analysis of other studies cited in the paper, clearly indicates that progesterone plays a very important role in the creation of myelin sheaths, possibly even Schwann cells as a whole, and also suggested the use of progesterone for disorders in myelination, such as multiple sclerosis.  

      Further work conducted by this group explored how progesterone could play a role in multiple sclerosis, which is more likely to develop in women when compared to men. Mouse models were once again used, with the mechanism of progesterone and testosterone in relation to the myelinating of pre-mature oligodendrocytes. After the mechanism was developed, progesterone was identified as playing a major role in the regulation of proliferation or the differentiation of myelinating cells, which is a significant event for those who develop multiple sclerosis. In an in vitro study, 3B-HSD (progesterone) was positively identified in cell cultures of pre-mature oligodendrocytes, suggesting that the synthesis of progesterone is a key function of oligodendrocytes’ maturation.  After this was understood, cerebellar slice cultures were captured from mice, and upon injection of progesterone, myelination of targeted axons was noticed. This effect was compared against knock-out mice, where the effect was not noticed. In an in vivo study, where male mice had spinal cord injuries, the mice were injected with progesterone showed an increase in the number of pre-mature oligodendrocytes produced, and a decrease in the number of astrocytes and inflammation factors like interleukin-1B.The combination of this research and those conducting similar research to Dr. Ghoumari’s group have identified not only does progesterone and other sex hormones play a major role in neurological aspects of human (and animal function), but also that these effects could be used to reverse the destruction of disorders related to the function of myelination in oligodendrocytes, such as multiple sclerosis.   

 

Citations:  

1. 1. Ghoumari, M. A., et.  al. (2020). Roles of Progestrone, Testosterone and Their Nuclear Receptors in Central Nervous System Myelination and Remyelination. MDPI, 21 (9). 3163; https://www.mdpi.com/1422-0067/21/9/3163 

2. 2. Schumacher, M. et.  al. (2022). Progestrone Synthesis in the Nervous System: Implications for Myelination and Myelin Repair. Frontiers in Neuroscience, 8, 9. https://pmc.ncbi.nlm.nih.gov/articles/PMC3274763/ 

How Gestures Influence Communication Across Communities

     Human communication is fascinating. It is something that is done every single day, oftentimes without giving it a second thought. People talk, engage, question, and interpret things millions of times a day and it is in these conversations that something occurs that might not be consciously thought of: gestural communication. The science shows that it is not paid as much attention to either. In Zielinski & Wakefield’s study titled “Language Proficiency Impacts the Benefits of Co-Speech Gesture for Narrative Understanding Through a Visual Attention Mechanism”, they cite a Gullberg and Holmqvist study that states that people look to the hands during communication less than 1% of the time, and mainly focus on a speaker’s face. They also cited a study in which children who were learning a mathematical concept looked to a teacher’s gestures 20% of the time, possibly because they were learning novel and potentially confusing information. These studies laid the foundation for the current study in which Zielinski & Wakefield hypothesize that bilingual children will pay attention to co-speech gestures in the language that they are not fluent in to aid in comprehension. To understand the nuance that co-speech gestures offer, they also use mismatching co-speech gestures and hypothesize that there will be more variation in understanding or a lack of recall due to its potentially distracting nature. 

Zielinski & Wakefield found that co-speech gestures increase recall potential in bilingual children if the presented gesture matches the content of the information being presented. The children devoted more attention to the visual gestures when the information was not in their first language. Ultimately, gestures proved to be very helpful in communicating when there was a potential barrier to understanding. 

Another community that often deals with communication barriers is individuals on the Autism Spectrum. In a study done by Bagdasarov et al., the researchers looked at co-speech gestures by individuals with Autism and neurotypical individuals in order to see the differences between the two groups. They found that adults with Autism primarily used gestures to indicate turn-taking within a conversation. These are known as interactive gestures which do not communicate information but rather aid in the structure of the conversation itself, such as who is speaking as indicated through pointing which indicates who’s turn it is or other hand gestures signaling that the speaker is not done speaking and does not wish to be interrupted. Ultimately it is seen that the benefit of co-speech gestures is generalizable across populations, serving as a helpful communication tool that aids with a variety of functions.  

References

Zielinski, N., Wakefield, E.M., 2021. Language proficiency impacts the benefits of Co-Speech gesture for narrative understanding through a visual attention mechanism. Proceedings of the Annual Meeting of the Cognitive Science Society 43 (43). htt ps://escholarship.org/uc/item/63r5d3qq.

Kim, E., Bagdasarov, A., Parish-Morris, J., Maddox, B., Brodkin, E., & Schultz, R. (2019). Atypicalities of Gesture Form and Function in Autistic Adults. Journal of Autism and Developmental Disorders, 49(4), 1438. https://doi.org/10.1007/s10803-018-3829-x

Progesterone and neuroprotection

Progesterone and neuroprotection

Progesterone is a very important hormone for the body functions of men and women. In women, ovaries form this hormone after ovulation, which plays an important role for preparing the body for menstrual cycle, pregnancy and conception. Progesterone helps preserve the uterine lining and prevents contractions that can cause an initial abortion when fertilized. In addition to progesterone reproduction, emotional stability, immune response affects metabolism and bone health. Women usually develop osteoporosis after menopause shows how important the role of progesterone is for bone health. It helps in controlling inflammation, controls sleep, and has worrying (anti -anxiety) properties. Progesterone is produced by the testicular and adrenal glands in men, but in lesser amounts than women. It affects sperm growth, testosterone synthesis and hormonal balance in general. In men, progesterone also supports heart health, mood stability and brain function. It supports normal hormonal balance by reducing the effects of additional estrogen.

Progesterone plays an important role in preserving brain function and helping to treat nerve damage. It acts as an anti-inflammatory agent, reduces the generation of toxic cytokines and increases overraction from the immune system that can damage neurons. This ability to control inflammation is quite important in diseases such as painful brain damage, stroke and neurodynative diseases, such as Alzheimer's disease. Progesterone reduces neuronal loss by regulating inflammatory reactions. This article "Brain-technical neurotrophic factors and related mechanisms that of mediation and affected progesterone-induced neuroprootection" by Mehravan Singh and colleagues discover neuroprotective properties of progesterone, which is especially in the connection of the brain-oriented neurotrophic factor (brain. " The material, which emphasizes the function of progesterone in a wide variety of neurological conditions, is in relation to the subject, including painful brain injury (TBI) and its potential neuroprottive properties.

The article "brain-technical neurotrophic factors and related mechanisms that mediate and affect progesterone-inspired neuroprooteten" emphasizes how important BDNF is for neurological survival, synaptic plasticity and brain health maintenance. Similarly, the progesterone article explains how progesterone therapy is linked to high level of neurotrophic factors, such as BDNF, which promotes neuroproote after trauma such as painful brain injury. The level of progesterone-inspired elevated BDNF gives the benefits of survival to neurons by activating TRKB receptors, which affects routes including PI3/AKT and ERK/Mapk, which are important for cellular survival and repair.

Progesterone receptor (PR) activation and neuro steroidogenesis as well as effects on neuronal function are just a couple of examples of progesterone modes of action as they occur according to the first article. Additionally, interactions reviewed within the context of BDNF roles' regulation, wherein levels of expression of the neurotrophin play a decisive role, could be linked with hypothesized engagement of certain microRNAs acting on the adjustment to progesterone treatment.

The therapeutic value of progesterone therapy for neurological conditions, such as TBI and neurodegenerative diseases, is highlighted in the two articles. The review puts forward that depending on how each progestin acts on BDNF and certain receptor types, different progestins can provide different results. Further research on the complicated interactions with BDNF and other signaling pathways must be conducted, as the original article also mentions the lack of clinical effectiveness in the use of progesterone for TBI despite encouraging results in animal models.

In summary, both papers are in agreement that progesterone is extremely promising as a neuroprotectant, which is very much mediated by BDNF and other neurotrophic processes. They offer a scientifically reasonable explanation of progesterone's role in brain health bringing reproductive biology to bear on essential neuroprotective properties and suggesting potential future therapeutic uses for neurological diseases. The relationship renders requisite justification for arguing that improvement of progesterone-derived treatments requires knowledge of the very mechanisms and processes engaged, such as the action of neurotrophins like BDNF.

References:

Theis, Verena, and Carsten Theiss. “Progesterone Effects in the Nervous System.” Anatomical record (Hoboken, N.J. : 2007) vol. 302,8 (2019): 1276-1286. doi:10.1002/ar.24121 

Singh, Meharvan et al. “Brain-derived neurotrophic factor and related mechanisms that mediate and influence progesterone-induced neuroprotection.” Frontiers in endocrinology vol. 15 1286066. 26 Feb. 2024, doi:10.3389/fendo.2024.1286066

PROGESTERONE AS A WAY TO PREVENT ANXIETY

 

PROGESTERONE AS A WAY TO PREVENT ANXIETY 

Progesterone has always been hormone-related, mostly in reproduction. However, it plays a big role in the regulation of mood, cognition, and neuroprotection. It can do this due to their interactions with neurotrophic factors like brain-derived neurotrophic factor (BDNF). The effect of progesterone over BDNF and how it can reduce anxiety symptoms and potentially prevent neurodegenerative diseases like Alzheimer’s are discussed in studies like “Progesterone Promotes Anti-Anxiety/Depressant-like Behavior and Trophic Actions of BDNF in the Hippocampus of Female Nuclear Progesterone Receptor, but Not 5α-Reductase, Knockout Mice” By. Cheryl A. Frye and “Brain-derived neurotrophic factor and related mechanisms that mediate and influence progesterone-induced neuroprotection” By. Singh Meharvan. 

Dr. Frye talks about progesterone and how it plays an important role in controlling mood and behavior, most specifically how it plays a role in anxiety disorders. BDNF plays a role in anti-anxiety and antidepressant-like effects due to the metabolic allopregnanolone characteristics.  Therefore, an increase in BDNF production and function would decrease the risk of anxiety and depressive disorders. This is where progesterone comes in, as it has been seen that progesterone improves BDNF and makes it work better therefore making neuronal building and overall function work better. On a similar note, Dr. Meharvan talks also mention the importance of progesterone and how it can decrease the risk factor of developing a neurodegenerative disease. As mentioned earlier, BDNF Is improved with the increase of progesterone. An improved version of his BDNF protein will decrease the chances of the creation of protein aggregates which are the main cause of Alzheimer’s. 

Both sources highlight the use of BDNF and how it is enhanced by progesterone in different regions of the brain. The first study notes that progesterone primes the hippocampus via BDNF by suggesting that GABA-A receptors are regulated by allopregnanolone and, therefore, BDNF function affects mood regulation. The second study talks about how progesterone makes BDNF function and expression stronger in synaptic plasticity helps the brain recover when damage is present and even prevents neurons from damaging as easily, therefore, protecting it from neurodegenerative disease. 

Both researchers talk about how progestin and its therapeutic effect on neurodegenerative disorders and neuropsychiatric illness. Based on the results in mice prototypes, progesterone has a positive effect on BDNF.  However, different types of progesterone target different areas of the brain and some have been shown to not affect the improvement of BDNF. Progestin (synthetic progesterone) has a different effect on the brain in contrast to natural progesterone, which could be a potential difficulty when developing pharmaceutical treatments.  Nonetheless, other studies have shown that natural progesterone has a low effect on and, in some cases, is unable to increase BDNF. This is why there should be further research on this specific area to determine which type of progesterone contributes better to the improvement of BDNF. 

WORK CITED: 

Singh, Meharvan, et al. “Brain-derived neurotrophic factor and related mechanisms that mediate and influence progesterone-induced neuroprotection.” Frontiers in endocrinology vol. 15 1286066. 26 Feb. 2024, doi:10.3389/fendo.2024.1286066

Frye, Cheryl A et al. “Progesterone Promotes Anti-Anxiety/Depressant-like Behavior and Trophic Actions of BDNF in the Hippocampus of Female Nuclear Progesterone Receptor, but Not 5α-Reductase, Knockout Mice.” International journal of molecular sciences vol. 26,3 1173. 29 Jan. 2025, doi:10.3390/ijms26031173

A Focus on Synaptic Densities Might be the Future of Neuroscience

Behavior, neural function and synaptic connectivity have long been suspected to be interconnected, but the advent of studying synaptic density using positron emission tomography might lead to definitive answers regarding mental illnesses and neurodevelopmental conditions. 

Unmedicated individuals, afflicted by major depressive disorder and post-traumatic stress disorder were shown to have significant synaptic loss and deficits in functional connectivity (Holmes et. al., 2019). The severity of depressive symptoms was also shown to be inversely correlated with synaptic vesicle glycoprotein 2A - an indirect means of measuring synaptic density. This lack of synaptic connectivity evident in both disorders - likely caused by various forms of stress - can also be linked to a loss of volume in the prefrontal conrtex, anterior cingulate cortex and the hippocampus, all of which are major areas of the brain associated with cognition and affect. The effects of these losses of synaptic connection are wider ranging than this. The research suggested low numbers of synapses are responsible for feeling more severe symptoms of these disorders, potentially highlighting neurodegenerative diseases targeting networks in the brain. 

The effects of substances in reversing these synaptic deficits is another facet of these disorders that has been studied. When treated with ketamine, increased antidepressant properties could be seen in models alongside an increase in the number and function of synaptic connections. Similar effects can also be seen in prefrontal cortex connectivity. Researchers theorize that enhancing synaptic connection and plasticity might be a means of restoring executive control, while also explaining the therapeutic effects of certain antidepressants. 

The use of radioligand binding to synaptic vesicle glycoprotein 2A provides an opportunity to study and understand these diseases better than we have before. It exists in synapses across the brain, in consistent concentrations at each synapse, making it the perfect molecule to track. Its functions are still a relative mystery, so focusing on understanding its purpose, alongside its use for in vivo modeling of synapses in the brain makes it the ideal focus for neuroscience research. 

Link to the paper: https://www.nature.com/articles/s41467-019-09562-7#citeas

The Role of Gestures as Co- Speech in Communication and Cognitive Processes

 Gestures are known to be “spontaneous hand movements” that are applied when speaking and communicating with others. Gestures are meant to represent information and emotions through the actions of the hands. Many claim that gestures showcase one’s competency in understanding language and perceiving expressions. Gesturing has become so common among humankind that many people don’t even realize when they gesture towards other people as a form of communication. Seemingly, it can be said that wherever there’s talking, there is gesturing.  

In the article “Language Proficiency Impacts the Benefits of Co-Speech Gesture for Narrative Understanding Through a Visual Attention Mechanism” by Natalia Zielinski and Elizabeth M. Wakefield, gestures aid in visual comprehension and help in visual attention as well. Using verbal language and gestures together is known as co- speech, which enhances language proficiency. By conducting a study between native English speakers and non native English speakers, participants were shown two different videos with the same information and words. One video had speech only and the other video had speech and gestures. Non native English speakers were able to comprehend what the video meant to say when it was accompanied with speech and gestures rather than just speech. The results concluded that non native speakers tend to gain advantage from speech and gestures compared to native speakers, showing us that gestures seem to provide an external aid in communication and understanding language. Non native speakers rely more on gestures as it helps them gain more insight on a new language, proving that combining speech with gestures helps new language learners gain comprehension through applying visual attention. 

In the article “The Role of Gesture in Communication and Cognition: Implications for Understanding and Treating Neurogenic Communication Disorders” by Sharice Clough and Melissa C. Duff discusses that gestures aren’t just related to the spoken language but they also play a crucial role in not just communication but also cognition. This seems to be especially true when talking about those with neurogenic communication disorders such as brain injuries. Gestures seem to structure thoughts and organize speech, and those with impaired communication gain the ability to use gestures as a compensation for verbal cues.  It was concluded that there seems to be a strong connection between cognitive function and the production of gestures as the understanding of gestures can provide perception into one’s cognitive processes.

Upon the relationship between both articles, it’s concluded that not only do both articles discuss the use of gestures in communication but also how critical gestures are and the positive aspects of speech combined with gestures. Both articles review how gestures actively guide towards attention as they help organize thoughts and help focus visual attention. The articles showcase how gestures aren’t just “add ons” to verbal communication but underlying tools in communication and comprehension that connect to cognitive function. 

References 

(1)     Clough, S.; Duff, M. C. The Role of Gesture in Communication and Cognition: Implications for Understanding and Treating Neurogenic Communication Disorders. Frontiers in Human Neuroscience 2020, 14 (323). https://doi.org/10.3389/fnhum.2020.00323.

(2)     Zielinski, N.; Wakefield, E. M. Language Proficiency Impacts the Benefits of Co-Speech Gesture for Narrative Understanding through a Visual Attention Mechanism. Proceedings of the Annual Meeting of the Cognitive Science Society 2021, 43 (43).