Watching the brain learn
Scientists at Göttingen University discover structural changes in adult mice brains as seen in young animals
2021-03-08
(Press-News.org) Understanding the cellular and molecular mechanisms underlying brain "plasticity"(how the brain can learn, develop and reorganise itself) is crucial for explaining many illnesses and conditions. Neurocientists from the University of Göttingen and University Medical Center Göttingen (UMG) have now managed to repeatedly image synapses, the tiny contact sites between neurons, in awake adult mice. They are the first to discover that adult neurons in the primary visual cortex with an increased number of "silent synapses" (ie newly formed synapses that are inactivated), lacking a certain protein (PSD-95), display structural changes that were previously only reported in young mice. This research by the Collaborative Research Centre CRC889 was published in PNAS.
It is well known that during early brain development, there are critical periods during which the brain is particularly plastic and individual experiences can trigger reorganization and adaptation in neuronal circuits. In developing brains, silent synapses are common and they help to functionally optimize the connections between principal neurons. The research teams of Professor Siegrid Löwel (University of Göttingen) and Professor Oliver Schlüter (UMG) had already discovered that the maturation of silent synapses requires postsynaptic density protein-95 (PSD-95) and closes early critical periods. However, the specific processes that govern whether synaptic connections are kept or removed depending on experience were largely unknown.
To investigate this, the researchers imaged neurons from the mouse visual cortex with a two-photon microscope while the animal was awake before and after a particular visual experience. As first author Rashad Yusifov from the University of Göttingen explains, "Previous studies have generally used anaesthetised mice but we now know that anesthesia itself can influence neuronal plasticity, which is why we did the current study in awake animals." Yusifov goes on to say, "This challenging technique, which entails repeatedly locating and imaging very tiny structures - around one-thousandth of a millimetre - known as dendritic spines, can only be carried out in a few laboratories in the world".
Researchers discovered that adult neurons deficient in PSD-95 display increased experience-dependent spine removal, an effect in the past only observed in young animals. Building on their previous discoveries, this collaborative research shows that PSD-95 deficient neurons display both functional and structural hallmarks of plasticity associated with a critical period. This means that neurons lacking PSD-95 keep a juvenile ability to restructure cortical connectivity even into adulthood. Senior author Professor Löwel adds, "Answering these key questions will not only help to understand the rules underlying brain development, functioning and learning, but will also open up new avenues to develop clinically relevant concepts to promote regeneration and rehabilitation for diseased and injured brains."
INFORMATION:
Original publication: Yusifov R, Tippmann A, Staiger JF, Schlüter OM* and Löwel S* Spine dynamics of PSD-95-deficient neurons in the visual cortex link silent synapses to structural cortical plasticity, PNAS 2021. DOI: 10.1073/pnas.2022701118
Paper available at: https://www.pnas.org/content/118/10/e2022701118
Contact:
Professor Siegrid Löwel
University of Göttingen
Department of Systems Neuroscience
Johann-Friedrich-Blumenbach-Institut für Zoologie und Anthropologie
Fakultät für Biologie und Psychologie
& Campus Institute for Dynamics of Biological Networks (CIDBN)
Von-Siebold-Straße 6, 37075 Göttingen, Germany
Tel: +49 (0) 551 39-20161 / 60
Email: sloewel@gwdg.de
http://systemsneuroscience.uni-goettingen.de/
[Attachments] See images for this press release:
ELSE PRESS RELEASES FROM THIS DATE:
2021-03-08
Professor Rosalind Gill, from City, University of London's Gender and Sexualities Research Centre, has today published a new report to mark International Women's Day.
The report - Changing the Perfect Picture: Smartphones, Social Media and Appearance Pressures - is based on research with 175 young women and nonbinary people in the UK.
Covering a range of issues - experiences of lockdown, feelings about 'body positivity', how to show support for Black Lives Matter - the research documents young people's persistent anger with a mass media that they deem 'too white', 'too heterosexual' and too focused on very narrow definitions ...
2021-03-08
Mental health issues such as burnout and psychological distress are matters for concern among young adults, and are even more pertinent in today's uncertain global climate. A recent paper by Yale-NUS College alumna Ms Joanna Chue (Class of 2019) and Assistant Professor of Social Sciences (Psychology) Cheung Hoi Shan identified five components of resilience that are applicable in Singapore's cultural context, and demonstrated that college students possessing a higher degree of resilience were less susceptible to burnout and psychological distress. By identifying learnable components ...
2021-03-08
Researchers at Paderborn and Bielefeld University are hoping to change this, and are discussing how the explainability of artificial intelligence can be improved and adapted to the needs of human users. Their work has recently been published in the respected journal IEEE Transactions on Cognitive and Developmental Systems. The researchers describe explanation as a social practice, in which both parties co-construct the process of understanding.
Explainability research
"Artificial systems have become complex. This is a serious problem - particularly when humans are held accountable for computer-based decisions," says Professor Philipp Cimiano, a computer scientist at Bielefeld University. Particularly in the ...
2021-03-08
In the EU alone, 78,800 men died of prostate cancer last year. While tumors discovered at an early stage can often be completely removed by surgery and radiation therapy, the prospects of successful treatment are reduced if the cancer has further metastasized. At present, physicians cannot predict drug response or therapy resistance in patients.
Three-dimensional structures
The team led by PD Dr. Marianna Kruithof-de Julio at the Urology Research Laboratory at the Department for BioMedical Research (DBMR) of the University of Bern and Inselspital Bern, has developed a new strategy for the generation of prostate cancer organoids that ...
2021-03-08
Along the western edge of Alaska's Aleutian archipelago, a group of islands that were inadvertently populated with rodents came to earn the ignominious label of the "Rat Islands." The non-native invaders were accidentally introduced to these islands, and others throughout the Aleutian chain, through shipwrecks dating back to the 1700s and World War II occupation. The resilient rodents, which are known to be among the most damaging invasive animals, adapted and thrived in the new setting and eventually overwhelmed the island ecosystems, disrupting the natural ecological order and driving out native species.
A coordinated conservation effort that removed the rats from one of the islands formerly known as Rat Island has become a new example of how ecosystems can ...
2021-03-08
Tocilizumab, an anti-inflammatory drug used to treat rheumatoid arthritis, improves outcomes in severely ill COVID-19 patients, finds the results of a new trial conducted in hospitals across India -- one of the world's most ethnically diverse countries. Researchers from the University of Bristol and Medanta Institute of Education and Research in India who led the study, published in The Lancet Respiratory Medicine, say it adds to existing evidence supporting the drug's use in critically ill patients.
Conducted in 12 public and private hospitals across India, the COVID ...
2021-03-08
Trolling and extreme levels of abuse can kill an online campaign but momentum can be maintained, and the energy and morale of exhausted activists effectively restored, by tactical retreat and taking time out, new research into the landmark 'No More Page 3' campaign in the United Kingdom shows.
Dr. Sarah Glozer of the University of Bath School of Management and Dr. Lauren McCarthy of the Royal Holloway University of London School of Business and Management studied the 'No More Page 3' campaign, which from 2012 lobbied The Sun mass-circulation newspaper to stop publishing a photo of a topless woman on page 3, a daily feature launched in 1970. Page 3, the No More Page 3 campaign argued, was a symbol of institutionalised sexism. The Sun removed the Page 3 feature ...
2021-03-08
The earliest multicellular organisms may have lacked heads, legs, or arms, but pieces of them remain inside of us today, new research shows.
According to a UC Riverside study, 555-million-year-old oceanic creatures from the Ediacaran period share genes with today's animals, including humans.
"None of them had heads or skeletons. Many of them probably looked like three-dimensional bathmats on the sea floor, round discs that stuck up," said Mary Droser, a geology professor at UCR. "These animals are so weird and so different, it's difficult to assign them to modern categories of living organisms just by looking at them, and it's not like we can extract their DNA -- we can't."
However, well-preserved fossil records ...
2021-03-08
Over 10,000 people in Europe use an assistance dog; think of guide dogs for people with a visual impairment, hearing dogs for people with a hearing impairment, medical response service dogs and psychiatric service dogs.
According to a UN-agreement and the Dutch law, these dogs are welcome in stores, hospitals and other public places. However, in practice, many assistance dog users and their dogs are regularly refused entry. In the Netherlands, four out of five assistance dog users indicate that they regularly experience problems with this.
Often, hygiene reasons are ...
2021-03-08
Researchers at the UAB have designed minimalist biostructures that imitate natural enzymes, capable of carrying out two differentiated and reversibly regulated activities thanks to a unique combination of structural and functional properties. The strategy used opens the door to the creation of "intelligent" nanomaterials with tailor-made combinations of catalytic functions.
There is an increasing interest in synthetic systems that can execute bioinspired chemical reactions without requiring the complex structures that characterise enzymes in their components. One of the most explored approaches is the self-assembly of peptides - molecules smaller than proteins - due to their biocompatibility and how their structural and functional properties can be controlled.
Researchers from the ...
LAST 30 PRESS RELEASES:
[Press-News.org] Watching the brain learn
Scientists at Göttingen University discover structural changes in adult mice brains as seen in young animals
