The temporal lobe is one of the four lobes of the human cerebral cortex. True to its name, it is located behind the temples in the lateral and middle parts of the brain. In its structure, we distinguish the left and right lobe. The primary function of the temporal lobe is communication. It turns out, however, that in some cases the lack of a large part of the brain does not really matter.
- The woman found out about the lack of the left temporal lobe in the fall of 1987.
- The unique anatomy of the brain did not interfere with her education and career advancement. For years, however, doctors believed that a woman should function much worse than she really does
- In the vast majority of people, most of the processing of language takes place in the left hemisphere of the brain. In the case of the woman, however, it turns out that the task of language processing has apparently shifted to her right hemisphere
- Therefore, it seems that one hemisphere is enough to acquire language fluency
- However, scientists emphasize that conclusions should not be drawn from the observation of one person. They plan, however, for further observations of the woman and other members of her family
- More information can be found on the Onet homepage
The unusual structure of the brain is a real treat for scientists who study it. Not surprisingly, then, when a patient with an “curious brain” approached researchers at the Massachusetts Institute of Technology (MIT), although they were observing the brain’s response to music at the time, they quickly referred it to the right person. A patient who, due to her atypical ailment, does not want to disclose her personal data, was referred to Prof. extra Evelina Fedorenko, who studies language using tools in cognitive science and neuroscience.
- See also: What happens to your brain when you drink? You will definitely limit your alcohol
Doctors were annoyed that the woman was functioning so well
Growing up in Connecticut, the patient is now 50. She first learned about the atypical structure of her brain in the fall of 1987, at the George Washington University Hospital. The lack of a left temporal lobe was not only terrifying for the patient, but also extremely embarrassing.
Doctors also did not help in understanding the problem of the unique anatomy of the brain, who, as the woman admitted, repeatedly irritated that in her case she should not have such a good vocabulary. “They made so many statements and conclusions without any scrutiny” — explained a woman quoted by Wired magazine. Unlike other doctors, Fedorenko had no prejudices about what a woman should and should not be able to do.
As it turns out, the lack of such a large piece of the brain had surprisingly little impact on the patient’s life. The woman graduated from university, made a career, and learned to speak fluently. According to the magazine «Wired», during the research conducted at MIT, the patient obtained a score of 98 percentiles in terms of vocabulary.
The possible cause of the defect is a stroke that occurred when the woman was still a child. Currently, this area of the brain contains only cerebrospinal fluid.
- See also: Graham will survive any car accident. How it’s possible? The doctors say
A real gem
The processing of the tongue is largely done in two main parts of the brain: the frontal and the temporal regions. U przeważającej części ludzi większość procesów przetwarzania języka odbywa się w lewej półkuli mózgu. For some, the load is evenly shared between the two hemispheres. The least frequent, however, is that the right hemisphere takes over most of the task.
During development, the temporal lobes develop first, while the frontal areas develop later, only around the age of 5. At this point, the language web is considered fully mature. Fedorenko and his team are watching the development of a wide variety of brain regions that play a role in language learning and understanding.
Unfortunately, the exact role of each of them has not yet been elucidated, and the way in which this system was formed is particularly difficult to study. This would require scanning the brains of children aged 1 to 3, whose language skills are just developing. “And we don’t have the tools to study the brains of children in this period” — Fedorenko explains in the magazine “Wired”.
For Fedorenko, the patient’s arrival was therefore a great opportunity to understand whether the temporal regions are a prerequisite for the formation of anterior lingual regions and how the remaining brain tissue reorganized cognitive tasks. «This case is a great opportunity to ask such a question. Sometimes there are gems that we try to use » — underlines Fedorenko in an interview with «Wired».
The researchers used functional magnetic resonance imaging (fMRI) to record the patient’s brain activity. During word-related tasks such as sentence reading, researchers looked for evidence of linguistic activity in the left frontal lobe. This brain activity was then compared with about 90 neurotypical controls (similar data were obtained from people with intact left temporal lobes).
Ultimately, the researchers concluded that the existence of temporal linguistic areas appears to be non-negotiable for the emergence of frontal linguistic areas. In their opinion, due to the lack of the left temporal lobe, the task of language processing had apparently simply been transferred to the patient’s right hemisphere. Thus, it seems that one hemisphere is sufficient to acquire language fluency.
Quoted by Wired magazine, Fedorenka’s PhD student Greta Tuckute also explains that while scientists are not entirely sure why, it seems that left-handed people are probably “wired in the right hemisphere.”
- See also: Parkinson’s can attack from the age of 21. A neurologist with four symptoms
Lessons for the future
Researchers emphasize that how little impact on a woman’s daily life has her unique brain anatomy shows how redundant large pieces of our brain can be. Fedorenko pays special attention to a procedure called hemispherectomy in children with epilepsy whose condition no longer responds to drug treatment. This surgery removes the seizure half of the brain.
“If half the brain can be removed and everything works fine, this suggests that in our typical brains there are many elements that are redundant” — Fedorenko says in an interview with «Wired». It is also worth emphasizing that in children, neuroplasticity, i.e. the ability of the nervous tissue to form new connections, is stronger.
Doctors explain, however, that no conclusions should be drawn from the observation of one person. In the future, Fedorenka’s lab hopes to learn much more from her unique patient’s brain. Scientists have already looked at an area of the brain known as the visual form area, which is thought to be responsible for decoding written word forms.
In neurotypical people, this area is located in the left part of the temporal cortex, but in women this function is dispersed throughout the organ. In future research, the researchers also intend to investigate how the absence of a woman’s temporal lobe affects her auditory system. Interestingly, the woman’s sister does not have the right temporal lobe and, like the patient, largely does not feel the consequences of this lack.
According to the neurobiologist, “this suggests that early childhood strokes are likely to have a genetic basis that could explain the lack of these brain areas”. Fedorenko also plans to investigate the other members of the woman’s family.
The examined patient admits that she hopes that thanks to the abovementioned tests, atypical brains will no longer be stigmatized.
Also read:
- Researchers have revived the brains of dead pigs. What could this mean? It’s hard to believe
- A difficult logic quiz in medicine. 12 points to get. How much will you manage?
- The worst foods for the brain. Trans fats, carbohydrates, alcohol