A team of researchers at UT Southwestern have made an interesting discovery that might help advance a better understanding of what makes humans’ cognitive abilities unique among primates.
Under the leadership of neuroscientist Genevieve Konopka, a lab at UT Southwestern Medical Center has become the first to employ innovative single-cell technology to investigate the posterior cingulate cortex — an area of the human brain believed to be at the center of high cognitive functioning. The goal was to shed light on what remains one of the most complex and fascinating frontiers in science: the evolution of human cognition.
The team’s latest findings were published in Nature this summer. Through a comparison of human and other primate brains, the researchers found larger numbers of specific cells in human brains that may bolster people’s ability to learn from experiences and recover from injuries. The team also found higher expressions of a gene called FOXP2, which is associated with language development in humans, within two types of human neurons.
For Konopka, these findings — especially when added to a comparison of genetic material from modern and ancient humans — could help better understand how the human brain evolved, distinguishing itself from other primates through key biological pathways.
“What’s new about this study is that it’s … created a new field of brain evolution where instead of focusing on the structure of the brain, now we can look at the genetic activity of the brain,” remarked Doug Broadfield, an associate professor of cell biology at the University of Miami Miller School of Medicine, according to The Dallas Morning News.
Konopka told the DMN that the study results initially took her aback.
She had expected to find greater numbers of brain cells called oligodendrocytes in human brains than in primate brains. Such cells are the unsung heroes of the brain’s support system. They insulate neurons to accelerate and boost signal transmission. They have come under the microscope in studies aiming to treat neurological disorders such as Alzheimer’s and schizophrenia.
Contrary to their expectations, Konopka and her team did not find a large number of mature oligodendrocytes but rather their precursors, known as pre-oligodendrocytes, in the human brain. This unexpected twist suggested the potential for these immature cells to enable the human brain to remain malleable, allowing for continuous learning and adaptation throughout adulthood.
Here may lie the instrumental difference accounting for humans’ cognitive divergence from other primates, according to the researchers.
The next step Konopka’s team will take is to use the very same single-cell technology to examine brain tissue from people with neurological disorders.
As extensively covered by The Dallas Express, the scientific community has made significant headway in developing new treatment protocols for those diagnosed with Alzheimer’s. Many of these have involved drugs that clear amyloid plaques from patients’ brains. These accumulations are believed to be behind the progressive degeneration of memory and thinking characteristic of the disease.
For instance, clinical trials of pharmaceutical giant Eli Lilly’s new drug, donanemab, saw promising results. Compared to the control group, participants receiving the drug reported 35% less cognitive decline, 40% less decline in their ability to perform daily activities, and a 39% lower chance of progressing to the next stage of the disease.
Lifestyle factors — such as being obese and eating highly processed foods — also appear to play a significant role in cognitive decline. A 2022 study from Brazil found that individuals could be at higher risk of dementia if they obtain more than 20% of their daily caloric intake from ultra-processed foods, as previously covered by The Dallas Express.