Don’t Overthink It: Could Higher Executive Functions Inhibit Foreign Language Ability?

It is well known that children are much better at learning languages than adults. After all, it is exceedingly rare for one to master a language to the extent of one’s native one, thinking and dreaming in one learned later in life. Nelson Mandela famously said, “If you talk to a man in a language he understands, that goes to his head. If you talk to him in his language, that goes to his heart.”

One paper sought to compile research on this very topic, finding many interesting details about bilingualism and brain development (Berken et al., 2017). One such finding is that the first few months are crucial in phoneme (the sounds of a language) acquisition, and that the speaking of various sounds and babbles in a tongue that will grow to be indistinguishable to that of a native speaker solidify as early as one year of age.

The exact reason that humans lose this ability to take on a new language like our native one is unknown, and there are many possible explanations. One may be simple necessity and opportunity, that as infants we both require learning the language around us to communicate basic needs and have little else to do or devote brain power towards. A common theory is that young children’s minds are especially malleable, and that the increased neuroplasticity that comes with youth is why learning languages becomes increasingly difficult as one ages.

A recent study, however, hints at an entirely different conclusion. The University of Liverpool conducted a study that focused on the language ability of non-native speakers, comparing sober participants to those who consumed a low-dose of alcohol (Renner et al., 2017). Surprisingly, despite controlling for a placebo effect and finding no change in self-reported language ability, native speakers of the language in question blindly tended to rate those in the alcohol consuming group with significantly higher conversational scores!

This surely came as a surprise. Alcohol is well-known for inhibiting what are known as ‘executive functions’, things such as memory, attention, comprehension, alertness, and pronunciation. This is why we picture a forgetful, sleepy, inattentive, slurring person when we imagine somebody who has had a lot to drink. While the study was notably a small amount of alcohol- comparable to a pint of beer for an average man- it seems counterintuitive that even slight inhibition of the previously mentioned functions would result in better performance in speaking a foreign language. Many of the things we consider ‘executive functions’ are things we consider key to speaking a learned language. What could be the cause of this finding?

The study admittedly offers that the anxiety suppressing effects of alcohol could be the source of the findings. A small amount of alcohol tends to make most people more social and less nervous, which could have resulted in more casual and natural language. While this is likely partially to blame for the findings, I suggest something else. That the suppression of these executive functions is precisely what allows for better language abilities rather than being a side-effect that is overcome by alcohol’s more social effects.

While it’s true that memory recall and pattern recognition are what comes to mind when we think about a foreign language, it’s important to recognize that it may not be that way for an infant- those most adept at learning languages of all humans (broadly). An infant is not an acute pattern recognizing and alert genius; they wield a still developing brain that even at its best is much less intelligent than a heavily intoxicated adult. The mentioned study implies that partially inhibiting these executive functions allows the human mind to take a step closer to its natural language-learning state; more of a blank canvas than refined machinery.

It’s hard to say what this could mean for the future of language education and instruction if these findings are supported, particularly if the anxiety reducing effects of alcohol can be controlled for. Should students in high-school Spanish take a shot of vodka before their lesson? No, probably not. But it is worth exploring the fact that the logical, pattern based method with which we teach and learn languages is very different from how an infant naturally learns, and that a more immersive, less analytical method may lead to better and faster results. Maybe it’s time we started learning with our hearts instead of our heads. But maybe it also means that shotgunning a White Claw before your next foreign language final isn’t as bad of an idea as it might seem.

References

Berken, J. A., Gracco, V. L., & Klein, D. (2017). Early bilingualism, language attainment, and brain development. Neuropsychologia, 98, 220-227. https://doi.org/10.1016/j.neuropsychologia.2016.08.031

Renner, F., Kersbergen, I., Field, M., & Werthmann, J. (2017). Dutch courage? Effects of acute alcohol consumption on self-ratings and observer ratings of foreign language skills. Journal of Psychopharmacology, 32(1), 116-122. https://doi.org/10.1177/0269881117735687

The Implications of a Plastic Brain

Among all of the fascinating aspects of the human brain and its abilities, its plastic nature is something that, in my opinion, stands out as particularly interesting. The plasticity of the brain refers to the organ’s ability to rewire itself in respect to one’s experiences and interactions with their environment. A specific example of the brain’s ability to change its wiring is when one acquires a new skill (such as a second language); the brain’s plasticity is the basis of one’s ability to learn and acquire new information!

In their 2016 paper titled Early bilingualism, language attainment, and brain development, Berken et al. explore the mechanisms and larger trends associated with brain development in conjunction with early postnatal bilingualism/language acquisition. They highlight the advantages of studying neural plasticity in bilinguals to analyze how the brain wires itself when it learns a skill early on in life, versus later, after the brain’s circuitry is less plastic and language pathways are already fully developed. In their review of a multitude of findings, they conclude that language acquisition is “…likely determined by a series of nested optimal periods of variable onset, offset, and duration that are influenced by both pre-programmed molecular signals and sensory experience” (224). Overall, in this paper, the researchers’ primary conclusion is that language acquisition is “...likely determined by a series of…optimal periods of variable onset, offset, and duration that are influenced by both pre-programmed molecular signals and sensory experience (Werker and Hensch, 2015)” (224). To make that more digestible for a non-scientific audience, this essentially means that the acquisition of language is determined by the time in which one learns it; this time is determined by biological actions at the molecular level, and one’s experiences as well. Furthermore they go on to say that when exposed to two languages from birth, there is equal proficiency in both languages due to the fact that the brain early on in life is especially plastic and “...the window for language development is open and because the brain has the capacity to rather easily streamline the wiring of neural circuitry serving the two languages” (224).

In her article titled Neuroplasticity: There is Always Hope After Stroke, Katie Brown aims to highlight the role of neuroplasticity in helping stroke victims recover from their brain injuries. Although strokes can be devastating and leave people in seemingly hopeless situations, Brown assures that “...those who experience a stroke or brain injury can continue to improve even years later. Our brains are able to relearn, restore, and compensate for damage that may have occurred” (Brown 1). Although the scientific paper by Berken et al. focuses on the very plastic nature of the brain during language acquisition in the first few years of one’s life, Brown’s article asserts that, despite the brain being more plastic in those early years of life, it remains plastic throughout one’s lifetime. She uses modern neuroscientific knowledge to give hope to individuals who were victims of strokes by highlighting the basics of neuroplasticity, and how one can go about relearning abilities they lost to regain some sort of function that may have been lost.

Conclusively, the crossover between Berken et al.'s paper and Brown’s article is evident upon inspection: the cross between knowledge achieved from research and the clinical implications of said knowledge are fascinating. Although both pieces of writing address the brain’s plasticity in different contexts, the underlying theme is the same: this remarkable ability can allow for recovery from strokes, underlies the ability to learn, and allows one to adapt to their environments.

References:

Berken, J. A., Gracco, V. L., & Klein, D. (2017). Early bilingualism, language attainment, and brain development. Neuropsychologia, 98, 220–227. https://doi.org/10.1016/j.neuropsychologia.2016.08.031

Brown, Katie. “Neuroplasticity: There Is Always Hope after Stroke.” Neuro Speech Solutions,         Neuro Speech Solutions, 7 Dec. 2021, https://www.neurospeechsolutions.com/client-blog/about-neuroplasticity-speech-therapy.

Tracking Phantoms of our Reality

Those in neuroscience have most likely heard of the neuroscientist V.S. Ramachandran and his work in studying abnormalities observed between the mind body relationship. He has inspired many, including me to have a deep curiosity about the world through the lens of neuroscience. In his book “Phantoms in the Brain”, he describes the phenomenon of phantom limp pain (PLP) and phantom limb sensation (PLS) in amputees. These experienced symptoms are associated with how the somatosensory cortex represents the entire body. This cortical mapping and the brains’ ability for neuroplasticity or cortical reorganization is one mechanism that explains why amputees still have the experience of the limb that is no longer present. To continue Ramachandran’s work 1998, I would like to briefly show where we are at with understanding PLP/PLS and what is being done to alleviate its symptoms. In spirit of Ramachandran, I would like to keep in mind the deeper implications of how we relate to our bodies, what is us and other, and what does it mean to be embodied beings.

PLP has a tremendous impact on quality of life in amputees. The number of amputees each year is increasing and not just due to traumatic car accidents but also due to the increase in diabetes and tumors. Many techniques used to alleviate PLP/PLS have evolved since the classical mirror therapy developed my Ramachandran. Since then, Transcranial Magnetic Stimulation (TMS) has been used over the cortical maps to activate the areas representing the absent limb. Acupuncture, drug treatments, and spinal cord stimulation are other therapies but none of them alone have had consistent success in dealing with PLP/PLS.

During a neuroscience seminar, I had the honor to listen to Dr. Dumanian’s talk on the incredible work he is doing with using Target Muscle Reinnervation (TMR) to alleviate PLP. His work seems very promising compared to the other therapies offered. What previous procedures had done was just innervated the amputated sense nerves into the nearby muscle flesh. Dr. Dumanian’s approach was to innervate the sense nerve with a nearby motor nerve that wouldn’t critically impact other motor functions. The reasoning behind is ingenious. Instead of having an open loop motor-sensory system with the nerve just embedded in the muscle, innervating the sense and motor nerve together creates the closed loop system. As Dr. Dumanian states, giving the sense nerve “something to do” could reduce the effects of cortical reorganization. Over the course of the year, patients reported PLP had reduced compared to the standard procedure.

TMR research focuses on what new treatments might look like in the future, but we are only looking at the peripheral nerve system. What have we learned in the CNS with cortical reorganization? What Ramachandran hypothesized was that neurons in the brain are always in competition with each other. If part of the somatosensory cortex is inactive due to an amputated limb, these areas don’t atrophy but get taken over by surrounding areas. A study that caught my attention was looking beyond the somatosensory cortex in how other areas are becoming reorganized. Particularly the right parietal cortex. The work done by Bao et al. 2021 in their study “Parietal Lobe Reorganization and Widespread Functional Connectivity Integration in Upper-Limb Amputees: A rs-fMRI Study”, looked at how areas in the right parietal cortex might become reorganized.

Amputees that have had upper-limb amputations have also been shown to have body image disorders. DSM-V describes this condition as having an intense anxiety due to the sense that their image of their body does not match reality. The right parietal cortex is a region of interest (ROI) since patients with lesions to this area have various body disorders. Using resting state fMRI (rs-fMRI), a technique used to measure brain activity but not needing to perform a task, the researchers have identified two indicators in the right parietal cortex that were significantly different from a healthy control group. They showed that there was a positive correlation with these indicators and self-reports of PLS. What these indicators show is that this is a decrease connectivity between various brain regions. The limitation to this study is that it is only post operative and that there needs to be a longitudinal study to see how these areas continually reorganize.

This study is a started point in understanding the brain and the body as a whole. Future research is needed not only for understanding the mechanisms behind reorganization, but for better therapies for amputees. The questions that still arises for me is how does the body (particularly the nervous system) maintain itself as a dynamical self-organizing system? In Dr. Dumanian’s work, he demonstrates that closed-loop systems are critical. In Bao’s et al. work, they showed that areas of the parietal cortex might serve as hubs to how we maintain our sense of embodiment. It is exciting to see where research has gone since Ramachandran and how more areas of research are converging on better understanding the complexities of life.

 

References:

Bao, Wei, H., Luo, P., Zhu, H., Hu, W., Sun, Y., Shen, J., Zhu, T., Lin, J., Huang, T., Li, J., Wang, Z., Li, Y., & Zheng, X. (2021). Parietal Lobe Reorganization and Widespread Functional Connectivity Integration in Upper-Limb Amputees: A rs-fMRI Study. Frontiers in Neuroscience, 15, 704079–704079. https://doi.org/10.3389/fnins.2021.704079

Dumanian, Potter, B. K., Mioton, L. M., Ko, J. H., Cheesborough, J. E., Souza, J. M., Ertl, W. J., Tintle, S. M., Nanos, G. P., Valerio, I. L., Kuiken, T. A., Apkarian, A. V., Porter, K., & Jordan, S. W. (2019). Targeted Muscle Reinnervation Treats Neuroma and Phantom Pain in Major Limb Amputees: A Randomized Clinical Trial. Annals of Surgery, 270(2), 238–246. https://doi.org/10.1097/SLA.0000000000003088