When a Concussion “Heals”, Is the Brain Really Back to Normal?

One of the most striking points for a talk I attended this semester on concussion was the idea that recovery is not always as complete as it seems. Dr. Jennifer Krizman explained that even after someone is medically cleared and their symptoms have resolved, subtle effects on the brain function, especially memory, can persist. This challenged the common assumption that once a concussion is “healed”, the brain automatically returns to its pre-injury state. 

This idea has become increasingly relevant in recent years as concussion awareness has increased. Current research supports this, underscoring that individuals who have had concussions may still experience issues with memory, attention, processing speed, and sleep. Even “mild” concussions can lead to lingering effects years after the injury (Denworth, 2024). This article also highlights research showing structural changes in the brain long after the concussion, supporting that the traditional symptom-based evaluations aren’t always enough to assess long-term memory. 

Dr. Krizman’s talk made a very similar point: the brain doesn’t always recover completely just because a person’s symptoms have resolved. Memory issues can be subtle and easily overlooked, especially when someone feels physically fine. This corresponds with what the Scientific American article describes as the long tail of concussion effects. This is where difficulties such as memory lapses or concentration problems can present even when other symptoms resolve (Denworth, 2024). 

Emerging research is now using more sensitive brain-based measures to track recovery. For instance, a 2025 study reported that athletes who have suffered a concussion still showed changes in brain-blood flow and structure for up to a year after they were medically cleared. These changes occurred in areas of the brain involved in thinking and memory, suggesting that even when symptoms have faded, the brain may not have fully regained its pre-injury state (American Academy of Neurology, 2025). This helps us understand why some people continue to have memory lapses or difficulty concentrating long after they feel “normal”. 

Understanding that the brain changes can shift our thinking of concussion as a short-lived injury that fully heals in a few weeks, it may be more accurate to view them as injuries that leave lasting changes in brain function. This understanding could have real-world impacts on how athletes and patients are monitored during and after their concussions, possibly even a recovery plan may be needed that extends beyond symptom resolution. 

To conclude, recognizing that brain changes may persist even after people feel physically better can lead to better guidelines for return-to-play, return-to-learn, and long-term monitoring. Research has validated the experience of people whose memory and cognitive performance remain altered and impaired after concussions; without such research, these accounts might be overlooked and dismissed because patients’ symptoms appear to be “gone”.

References:

Denworth, L. (2024, November 19). Concussions Are Remarkably Common and Can Cause Long-Term Problems. Scientific American. https://www.scientificamerican.com/article/concussions-are-remarkably-common-and-can-cause-long-term-problems/ 

American Academy of Neurology. (2025, March 14). Do brain changes remain after recovery from concussion?. ScienceDaily. Retrieved February 27, 2026 from www.sciencedaily.com/releases/2025/03/250312190835.htm

Understanding Language By: Isabel Korstanje

  Understanding Language

 

The ability to communicate and understand is taken for granted on a daily basis. A simple typo, stutter, whisper can change the trajectory of various events. To understand is to be able to observe and learn. Our senses are supreme to this concept of ‘understanding’ and is something that we as humans utilizes every second of every minute. To see, is to identify and analyze. It is a way to provide a name, discernment, and for some species another day of survival. To be able to hear allows us to sense or understand without having to identify. Both together can evolve and create a stronger comprehension of communication. 

In a seminar done recently at Loyola University, Natalia Zielinski and Elizabeth M Wakefield spoke on the correlation between physical gestures and understanding language. They focused on a study done on bilingual students and their understanding of a spoken message, specifically if that understanding was enhanced by gestures.2 This was done through storytelling, with specific details or descriptions being heavily emphasized through physical gestures. The children were then individually asked about certain details mentioned throughout the story. This determined if the child was more likely to recall a certain event or turning point in the story when gestures were used.2 The focus was the correlation between a visual stimulus and language proficiency. 

An article by Cody Cottier, “‘Mind-blowing’ baby chick study challenges a theory of how humans evolved language”, focused on baby chicks finding another way in which language can be processed and strengthened. The study in which the article follows focuses on how animals utilize their sense of hearing to understand and form connections to others from the same or different species. The bouba-kiki study revealed that baby chickens use specific sounds to identify shapes, forming a linkage with sounds and visual information.1 The sound reveals not only the source, but the pitch and volume, which may also reveal further physical details of said source. 

Both articles present a strengthening of language understanding via auditory and visual information. Similarly, both share the same ‘age group’ of both chickens and humans, with early development playing a critical part of the studies. The senses are presented as crucial during the developmental stages of early life, with the brain combining what we hear and see when analyzing or recalling. 

 

 

                                         

Refrences

 

(1)     Blum, D. (2024). Baby chicks pass the bouba–kiki test, challenging a theory of language. Scientific American. https://www.scientificamerican.com/article/baby-chicks-pass-the-bouba-kiki-test-challenging-a-theory-of-language/

(2)     Zielinski, N., & Wakefield, E. M. (2021). Language proficiency impacts the benefits of co-speech gesture for narrative understanding through a visual attention mechanism. Loyola University, Access Date, March 2nd, 2026

 

From Myelin Loss to Memory Decline: How Chronic Cellular Stress Drives Neurodegeneration

 Pelizaeus-Merzbacher disease (PMD), is a rare neurological disorder that disrupts myelin in the brain. A mutation in the PLP1 gene affects oligodendrocytes which are the cells that produce myelin. When PLP becomes mutated, it results in a build up inside the cell and stress becomes a factor in the endoplasmic reticulum. To counteract the stress, the body has an integrated stress response (ISR) to protect itself from any harm. In PMD, the ISR is activated for longer than it needs to be and ends up doing more harm than good which ends up killing the cells its supposed to protect. As oligodendrocytes die, myelin production stops and the brain enters a state of hypomyelination. In a study by Yanan Chan et al., researchers used a mouse model to discover, that deleting a protein named PERK reduced ISR activity. This resulted in the mice living two weeks longer with improved myelination. Over working the ISR can do the opposite of what its supposed to and actually drive the progression of disease.

On the contrary, Alzheimer's diseases isn't caused by myelin loss, instead its caused by damage to the hippocampus resulting in memory loss. During a study by Sabitha, K.R. et al., researchers used advanced single-cell techniques to show that the human brain can still generate immature neurons even in a disease state. One specific neuron, CA1, shows early changes in gene activity before any significant damage is visible. Disease isn't something that happens spontaneously, it is a slow build up of molecular changes that weaken memory circuits over time.

What connects the two studies is chronic cellular stress. In PMD, the ISR is supposed to playing a supportive role but instead does the oppoistire once its played its part for too long resulting in making the progression of disease quicker. In Alzheimer's disease, stress that accumulates over time slowly destroys the hippocampus and can't be seen until enough is lost. In both diseases, the damage starts at the molecular level. In PMD's case its myelin loss and in Alzheimer's it is the buildup of plaque. Understanding the shift of when molecular process are disrupting instead of helping would be key in slowing the development of neurodegeneration.

Chen, Y., Kunjamma, R.B., Lin, K. et al. Integrated stress response inhibition prolongs the lifespan of a Pelizaeus-Merzbacher disease mouse model by increasing oligodendrocyte survival. Nat Commun 17, 1285 (2026). https://doi.org/10.1038/s41467-025-68045-0

Disouky, A., Sanborn, M.A., Sabitha, K.R. et al. Human hippocampal neurogenesis in adulthood, ageing and Alzheimer’s disease. Nature (2026). https://doi.org/10.1038/s41586-026-10169-4

Why have there not been any cures for oligodendrocyte-related diseases?

 I had the privilege to attend a neuroscience seminar where Dr. Yanan Chen spoke about her research on Pelizaeus-Merzbacher Disease and oligodendrocyte survival. Due to my interest regarding the topic of hypomyelinated neuronal diseases, I made the decision to research and learn more about it and discuss my findings. Because there is little to be known about the direct causes of Multiple Sclerosis and, therefore, finding a cure, I find it interesting to learn about other similar diseases, such as PMD, that affect the myelination process. Dr. Chen’s research and other studies, however, are changing this by showing possible solutions or resistance therapies to these diseases. 

Before presenting her findings and research during the NEUR 300 seminar, Dr. Yanan Chen presented a study that shows how Pelizaeus-Merzbacher Disease negatively impacts the survival of oligodendrocytes and how integrated stress response inhibitors can aid in preserving the oligodendrocytes’ survival, despite the effects of PMD. They focused mainly on the male PMD mouse model Jimpy to “determine the impact of integrated stress response (ISR) on the oligodendrocyte response to mutant PLP expression” (Chen 2025). The study found that when the ISR-triggering eukaryotic initiation factor (eIF) 2α kinase was successfully inactivated, this process correlates with the survival of oligodendrocytes and myelination in the CNS. 

I became interested in this particular study because, when doing my own research, I found that I knew from previous research and courses at Loyola University Chicago that Multiple Sclerosis was a similar disease in the sense that it involves hypomyelination of axons, and therefore, I was wondering why there was not a cure yet found for either disease. I found a supplementary study by Doghish, Elazazy, Mohamed, Mansour, Ghanem et al. (2023), that describes how miRNAs could possibly play a significant role in Multiple Sclerosis "pathogenesis, diagnosis, and therapeutic resistance", and I was immediately intrigued (Doghish 2023). The study revealed that the diagnosis of Multiple Sclerosis was difficult “due to the lack of disease-specific biomarkers” and therefore, depends on ruling out numerous disabilities (Doghish 2023). Because of this, the researchers hope to further study “biological features of miRNAs in MS and explore their potential as a therapeutic target” (Doghish 2023). 

When reviewed as a whole, these investigations only provide a broad and hopeful conclusion to the problem, however, more research and findings must be done to provide a convincing conclusion overall. While Dr. Chen showed that the ISR-triggering eukaryotic initiation factor (eIF) 2α kinase was completely non-functioning, the survival of the oligodendrocytes and myelination of the CNS increased, Doghish, Elazazy, Mohamed, Mansour, Ghanem et al. (2023) showed that there is much to be revealed in the future regarding the future of miRNAs in multiple aspects of MS. These new discoveries and sciences may be used to treat not only PMD and MS, but also, provide a different approach to diagnosing and treating diseases involving the structure and functionality of the CNS. Together, these investigations reveal a bridge between neurological understandings and discussion, and therefore, provide hope for the future of curing uncurable diseases. 

 

References: 

Chen, Y., Kunjamma, R.B., Lin, K. et al. Integrated stress response inhibition prolongs the  lifespan of a Pelizaeus-Merzbacher disease mouse model by increasing  oligodendrocyte survival. Nat Commun (2025). https://doi.org/10.1038/s41467- 025-68045-0  

Doghish, Ahmed S, et al. “The Role of MiRNAs in Multiple Sclerosis Pathogenesis,  Diagnosis, and Therapeutic Resistance.” Pathology, Research and Practice, vol.  251, 1 Nov. 2023, pp. 154880–154880, https://doi.org/10.1016/j.prp.2023.154880.  Accessed 19 Apr. 2024. 

Nature and Nurture in Neurohealth

Today, people rely on their 5 senses to see the beauty of nature and life. The sense of sound is essential in listening to music, people, and the world around them to be able to make everlasting memories. Sound is, however, more than mere hearing; it is the precursor to overall health and function of the brain. What if auditory processing can be identified for neurological health in people whether genetically or man?

 Not long ago I had the opportunity to listen to Dr. She worked to determine whether concussions could be identified in children through brain responses to sound. Krizman’s research on concussions was aimed at identifying if brain responses to sound were identification of concussions in children (Krizman, 2023) by studying fundamental frequency (FO), “also known as the pitch cue”, and the frequency following response (FFR) and its effects on auditory processing following a concussion. One of the first observations was the effect of concussions on neural timing. A concussion therefore hampers the coordinated firing of neurons, which constitutes sound encoding. Brain responses are desynchronized, signals are dispersed, and arranged electrophysiological potentials of pitch have reduced efficacy. Finally, in those who have had a concussion, the auditory brainstem encoding of sound was tested by looking at FFR. There was a weakening of the F0 pitch, reduction of the response, and less accurate tracking of the sound in response to stimuli. In summary, concussions have adverse effects on the subcortical encoding of information, and this understanding can be a focal point in identifying injury or recovery.

A Neuroscience-based research study I came across, “Neural coding of formant-exaggerated speech and nonspeech in children with and without autism spectrum disorders” by Chen et al. Specifically, the TD children and children with ASD underwent testing of neurophysiological encoding of speech sounds at the neural level through a mechanism known as the frequency following response (FFR). The first conclusion was that children with ASD lacked automatic neural enhancement of exaggerating their speech compared to TD children. An exaggerated speech in TD children resulted in a better neural response, and the brainstem response was more accurate than in children with ASD whose neural response did not increase significantly and there was no brainstem response to enhancement. This reflects the influence on the cortex, which normally makes for its enhancement towards the brainstem responses to meaningful speech. In ASD children, the lack of enhancement meant speech was neurologically prioritized differently than in TD children. Finally, this can have a downside effect on the language development of children with ASD. From the neural differences, research can point towards early sensory contributions to language and differences in communication when it comes to autism.

While Dr. Krizman’s study focused on an injury and Dr. Chen’s was developmental, both studies demonstrated how the auditory system can be susceptible to disruption in the brain, leaving speech processing vulnerable. In concussed children, there was delayed neural timing in the brainstem that affected the encoding of speech, and in ASD children, their exaggerated speech was not able to lead to the neural enhancement experienced by TD children due to their altered use of the cortex. Ultimately, this shows a neurodevelopment comparison to neurotrauma and its effects in areas of the brain, leading to implications. This can then potentially be used to catch indicators of neurological health

Kraus, N., Thompson, E. C., Krizman, J., Cook, K., White-Schwoch, T., & LaBella, C. R. (2016). Auditory biological marker of concussion in children. Scientific Reports, 6(1). https://doi.org/10.1038/srep39009

Chen, F., Zhang, H., Ding, H., Wang, S., Peng, G., & Zhang, Y. (2021). Neural coding of formant‐exaggerated speech and nonspeech in children with and without autism spectrum disorders. Autism Research, 14(7), 1357–1374. https://doi.org/10.1002/aur.2509

The Hidden Impact of Concussions

A concussion is often characterized as a temporary brain injury associated with headache, dizziness and memory problems; however emerging neuroscience research has suggested that it has evident effects on the brain's ability to process sound and speech, extending beyond the anticipated symptoms. More specifically, causing difficulty in listening and communicating which possesses the question if hidden symptoms of brain injuries and often explained away by fatigue and distraction?

A few weeks ago I had the opportunity to listen to Jennifer Krizman’s presentation on the auditory biological markers of concussion in children, where she discussed how concussions impact the way the brain processes speech. She studied frequency following response, which captures how accurately the brain responds to sound. Her presentation and emergent dissolves suggest that concussion can have a more significant effect on the sensory processing system compared to traditional symptom-dependent diagnoses. 

Similar findings are studied in a recent study tilted Persistent post-concussion symptoms include neural auditory processing in young children which explained how concussions influence auditory processing after initial symptoms seem to improve. The researchers found that children with concussions have weaker neural encoding of speech sounds, specifically for pitch-related cues which are integral in unders†ådning everyday speech. These findings support Kriman’s idea that the effect of concussion can still be present in the brain after symptoms seem to improve, which indicates recovery can not be solely judged by symptom reports.

How Hands Help and Hurt

 When we think about learning, we usually focus on what is said. We assume that words carry the meaning and that gestures are just extra movement. But research in cognitive science suggests that our hands may play a much larger role in comprehension and memory than we realize. Research in cognitive science shows your hands shape, meaning, and memory. Gesture shifts comprehension. Gesture also disrupts comprehension. Natalia Zielinski and Elizabeth Wakefield tested this in 2021. They studied Polish-English bilingual children. They asked one question. Do gestures help more when language feels harder? 

Children watched stories in English and Polish. English served as stronger language. Polish served as weaker language. The storyteller used two gesture types. Matching gestures reinforced speech. Mismatching gestures added unstated details. Researchers tracked eye movement. They measured recall after each story. The results showed patterns. Children recalled more when matching gestures paired with weaker language. They looked at their hands more during weaker language. Gestures worked as support. When speech strained processing, children shifted attention to visual input. Mismatching gestures failed to help. Some reduced accuracy. 

Nicole Dargue found similar effects. Gestures aligned with speech improved comprehension. Gestures misaligned increased cognitive load. Cognitive load drives this pattern. Working memory holds limited information. Adults store about four chunks at once. Second language processing consumes capacity. Matching gestures distribute information across visual and verbal systems. Mismatching gestures demand integration of extra content. Capacity overload reduces recall. 

Zielinski’s eye-tracking data explains the mechanism. Attention shifts are based on difficulty. Gesture helps when you allocate focus. Gesture fails when attention splits. 

When you teach or present, do your hands mirror your words? Or do they introduce new content? In bilingual classrooms, gesture choice shapes equity. Students learning in a weaker language benefit from aligned visual cues. Extra motion without alignment strains memory. 

You communicate every day. When content grows complex, where do your eyes move? 
When you speak, do your gestures support your message or compete with it? 

References

Dargue, N., & Sweller, N. (2020). Learning stories through gesture: Gesture’s effects on child and adult narrative comprehension. Educational Psychology Review, 32(1), 249–276.

https://doi.org/10.1016/j.ridd.2021.104000

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.

(02.03.26) - Elizabeth Wakefield - OneDrive