Press releases

Bats live in a world of sounds. They use vocalizations both to communicate with their conspecifics and for navigation. For the latter, they emit sounds in the ultrasonic range, which echo and enable them to create an “image" of their surroundings. Neuroscientists at Goethe University Frankfurt have now discovered how Seba's short-tailed bat, a species native to South America, manages to filter out important signals from ambient sound and especially to distinguish between echolocation and communication calls. 

FRANKFURT. Seba's short-tailed bat (Carollia perspicillata) lives in the subtropical and tropical forests of Central and South America, where it mostly feeds on pepper fruit. The animals spend their days in groups of 10 to 100 individuals in hollow trunks and rocky caverns, and at night they go foraging together. They communicate using sounds that create distinct ambient noise in the colony – like the babble of voices at a lively party. At the same time, the bats also use vocalizations to navigate their surroundings: a phenomenon known as echolocation, for which they emit ultrasonic sounds that reflect off solid surfaces. The animals then assemble these echoes into an “image" of their surroundings. 

But how does Seba's short-tailed bat manage to filter out important sounds from constant ambient noise? A common explanation is that the brain constantly predicts the next signal and reacts more strongly to an unexpected signal than to an expected one. This is referred to as deviance detection, and neuroscientists led by Johannes Wetekam and Professor Manfred Kössl from the Neurobiology and Biosensors Working Group at the Institute of Cell Biology and Neuroscience at Goethe University Frankfurt are exploring its mechanisms. Together with colleagues, they were already able to show in 2021 that signal processing does not begin in high-level regions of the brain but already in the brainstem, which is responsible for controlling vital functions such as breathing and heart rate. However, these studies only used artificial stimuli that are not meaningful to the animals. 

In a study recently published, the team led by Wetekam and Kössl repeated the experiments with natural communication and echolocation calls. “With our study, we wanted to find out what happens in deviation detection when, instead of meaningless stimuli, ones are presented to Seba's short-tailed bat that actually occur in its auditory world," says Wetekam, summing up. 

To do this, two electrodes the thickness of a human hair were inserted under the bats' scalps to record their brain waves. Although this was painless for the animals, the measurements were carried out under general anesthetic, as any movement could distort the results. 

The bat's brain reacts to sounds even when the animal is anesthetized and fast asleep. Either echolocation or communication calls were then played to the animals, each interspersed with the other sound, with a 10% probability of it occurring. 

It was then possible to read from the brain waves measured that the brainstem processes echolocation and communication calls differently. While infrequent echolocation sounds indeed induced stronger signals than frequent ones – i.e. showed deviation detection – in the case of communication sounds, the probability of them occurring did not influence the strength of the response. “Bats probably need to react faster during echolocation than when communicating with conspecifics," presumes Manfred Kössl. “The brainstem is the first station in the brain to receive the acoustic signals, which is why calculating the probability of echolocation calls might be necessary first of all there, and especially their echoes, so that the animal can dodge obstacles in good time." The stronger response to less frequent calls is presumably due to better neural synchronization. 

The study also showed that the brainstem can utilize other features of bat calls for deviance detection, such as rapid changes in frequency or volume, in addition to differences in pitch. “This is astonishing, as the brainstem is a rather primitive part of the brain that scientists did not previously think capable of any substantial involvement in signal processing," says Wetekam. “They saw its role more in receiving signals from the auditory nerve and transmitting them to high-level regions of the brain." 

These findings might also be important in relation to medical applications in humans. For example, the low-level regions of the brain ought to be included when studying diseases such as ADHD or schizophrenia, which are associated with impaired processing of extraneous stimuli. The fact that the bat brainstem processes various complex acoustic signals differently can also help scientists to understand how the brain deciphers and processes complex human speech. 

Publication: Johannes Wetekam, Julio Hechavarria, Luciana López-Jury, Eugenia Gonzáles-Palomares, Manfred Kössl: Deviance detection to natural stimuli in population responses of the brainstem of bats. Journal of Neuroscience (2024) https://doi.org/10.1523/JNEUROSCI.1588-23.2023

Background: How the brain filters out sounds (2022)
https://aktuelles.uni-frankfurt.de/english/how-the-brain-filters-out-sounds 

Picture download: https://www.uni-frankfurt.de/150019112 

Caption: Seba's short-tailed bat (Carollia perspicillata) filters out important signals from ambient sound and distinguishes between echolocation and communication calls. Photo: Julio Hechavarría, Goethe University Frankfurt 

Further Information
Johannes Wetekam
Neurobiology and Biosensors Working Group
Tel.: +49 69 798-42066 '
wetekam@bio.uni-frankfurt.de 

Professor Manfred Kössl
Institute of Cell Biology and Neuroscience
Head of the Neurobiology and Biosensors Working Group
Goethe University Frankfurt
Tel.: +49 (0)69 798 42052
Koessl@bio.uni-frankfurt.de
https://www.bio.uni-frankfurt.de/36526663/Abt__K%C3%B6ssl___Biowissenschaften 

Twitter/X: @JohannesWetekam @goetheuni

Editor: Dr. Markus Bernards, Science Editor, PR & Communication Office, Theodor-W.-Adorno-Platz 1, 60323 Frankfurt am Main, Tel: +49 (0) 69 798-12498, bernards@em.uni-frankfurt.de.

Incidences of eating disorders such as bulimia and anorexia are becoming more common, especially among young people. In addition to the urgent need for medical and psychological therapy, the dental health of those afflicted also bears consideration. A new offer from Goethe University's Center for Dentistry, Oral and Maxillofacial Medicine (Carolinum) offers advice, prevention and therapy. 

FRANKFURT. Eating disorders such as anorexia and bulimia can lead to severe dental damage. The cause: due to frequent vomiting, the pH value in the oral cavity is acidic over a longer period of time and the teeth gradually lose their minerals. This can result in discoloration and indentations on the teeth, which can also become more sensitive. If the tooth structure is subject to frequent acid attacks, the shape of the tooth may change, potentially resulting in pain and tooth decay. 

Early dental intervention can prevent damage to the tooth's structure and treat existing erosions. To this end, Prof. Jan-Frederik Güth, Head of the Polyclinic for Dental Prosthetics, and Prof. Stefan Rüttermann, Head of the Polyclinic for Tooth Preservation, have set up an interdisciplinary consultation specialized in dental therapy for eating disorders. An early focus on the connection between eating disorders and dental health can help avoid extensive dental treatment at a later stage, and therefore save on high costs. 

As part of the consultations, dentists Miriam Ruhstorfer and Charlène Bamberg offer patients two-phased advice. The initial focus is on diagnostics and prophylaxis, including an intraoral scan that enables a three-dimensional analysis. Also part of this stage is oral hygiene training aimed at optimizing the cleaning of the teeth. Offering additional protection to the teeth while simultaneously also strengthening them is fluoride, administered with the help of custom-made transparent splints. The second stage encompasses the treatment of existing damage to the tooth structure and, if necessary, to the jaw joints, as well as dental check-ups for the early detection of new damage. 

Images for download: https://www.uni-frankfurt.de/149521941 

Caption: Severely damaged teeth of a bulimia patient before and after treatment. (Photo: Carolinum) 

Further information
Miriam Ruhstorfer/Charlène Bamberg
Polyclinic for Dental Conservation
Center for Dentistry, Oral and Maxillofacial Medicine
Faculty of Medicine
Goethe University Frankfurt
Tel. +49 (0)69 6301-4247
E-Mail es-zahnmedizin@med.uni-frankfurt.de
www.carolinum.uni-frankfurt.de

Editor: Dr. Anke Sauter, Science Editor, PR & Communication Office, Tel: +49 (0)69 798-13066, Fax: +49 (0) 69 798-763 12531, sauter@pvw.uni-frankfurt.de

If gravitational condensate stars (or gravastars) actually existed, they would look similar to black holes to a distant observer. Two theoretical physicists at Goethe University Frankfurt have now found a new solution to Albert Einstein's theory of general relativity, according to which gravitational stars could be structured like a Russian matryoshka doll, with one gravastar located inside another. 

FRANKFURT. The interior of black holes remains a conundrum for science. In 1916, German physicist Karl Schwarzschild outlined a solution to Albert Einstein's equations of general relativity, according to which the center of a black hole consists of a so-called singularity, a point at which space and time no longer exist. Here, the theory goes, all physical laws, including Einstein's general theory of relativity, no longer apply; the principle of causality is suspended. This constitutes a great nuisance for science: after all, it means that no information can escape from a black hole beyond the so-called event horizon. This could be a reason why Schwarzschild's solution did not attract much attention outside the theoretical realm for a long time – that is, until the first candidate for a black hole was discovered in 1971, followed by the discovery of the black hole in the center of our Milky Way in the 2000s, and finally the first image of a black hole, captured by the Event Horizon Telescope Collaboration in 2019. 

In 2001, Pawel Mazur and Emil Mottola proposed a different solution to Einstein's field equations that led to objects which they called gravitational condensate stars, or gravastars. Contrary to black holes, gravastars have several advantages from a theoretical astrophysics perspective. On the one hand, they are almost as compact as black holes and also exhibit a gravity at their surface that is essentially as strong as that of a black hole, hence resembling a black hole for all practical purposes. On the other hand, gravastars do not have an event horizon, that is, a boundary from within which no information can be sent out, and their core does not contain a singularity. Instead, the center of gravastars is made up of an exotic – dark – energy that exerts a negative pressure to the enormous gravitational force compressing the star. The surface of gravastars is represented by a wafer-thin skin of ordinary matter, the thickness of which approaches zero. 

Theoretical physicists Daniel Jampolski and Prof. Luciano Rezzolla of Goethe University Frankfurt have now presented a solution to the field equations of general relativity that describes the existence of a gravastar inside another gravastar. They have given this hypothetical celestial object the name "nestar" (from the English “nested"). 

Daniel Jampolski, who discovered the solution as part of his Bachelor's thesis supervised by Luciano Rezzolla, says: “The nestar is like a matryoshka doll", adding that, “our solution to the field equations allows for a whole series of nested gravastars." Whereas Mazur and Mottola posit that the gravastar has a near infinite thin skin consisting of normal matter, the nestar's matter-composed shell is somewhat thicker: “It's a little easier to imagine that something like this could exist." 

Luciano Rezzolla, Professor of Theoretical Astrophysics at Goethe University, explains: “It's great that even 100 years after Schwarzschild presented his first solution to Einstein's field equations from the general theory of relativity, it's still possible to find new solutions. It's a bit like finding a gold coin along a path that has been explored by many others before. Unfortunately, we still have no idea how such a gravastar could be created. But even if nestars don't exist, exploring the mathematical properties of these solutions ultimately helps us to better understand black holes". 

Publication: Daniel Jampolski, Luciano Rezzolla: Nested solutions of gravitational condensate stars. Classical Quantum Gravity (2024) https://doi.org/10.1088/1361-6382/ad2317 

Images for download: https://www.uni-frankfurt.de/149345988 

Caption: According to findings by physicists at Goethe University Frankfurt, a gravastar could look like a matryoshka doll. Image: Daniel Jampolski and Luciano Rezzolla, Goethe University Frankfurt 

Further information
Professor Luciano Rezzolla
Institute for Theoretical Physics
Goethe University Frankfurt
Phone: +49 (69) 798-47871
rezzolla@itp.uni-frankfurt.de
https://astro.uni-frankfurt.de/rezzolla/

Editor: Dr. Markus Bernards, Science Editor, PR & Communication Office, Theodor-W.-Adorno-Platz 1, 60323 Frankfurt, Tel: +49 (0) 69 798-12498, bernards@em.uni-frankfurt.de

The "InterCare" research project carried out at Goethe University Frankfurt's Faculty of Educational Sciences shines a spotlight on young people in training who care for older adults. Initial research already shows that society is far less aware of this group than it should be. 

FRANKFURT. About one in eight young people undergoing training – as pupils, apprentices or university students – is wholly or partially responsible for the well-being and care of older, sick or disabled relatives or other loved ones, a study by the German Centre for Higher Education Research and Science Studies shows. This group is even larger than that of students who care for children. 

Young women as well as young adults with a migratory background, irrespective of their gender, are more likely to face the pressures of simultaneously managing care and education. "This huge group of individuals is completely overlooked in the public eye," says Dr. Anna Wanka, whose research focuses on finding out more about the everyday life of these young people, the challenges they are facing, and on how to support them. Being responsible for an older person often influences not only academic performance, but also the decision for or against university or further education, especially in another city. Those who do decide to continue with their education often have a guilty conscience, feel shame towards peers and lecturers, and face daily hurdles in their efforts to reconcile education and care. 

"InterCare" is the first comprehensive research project to take a detailed look at this group. It will start officially in October 2024, from which point onwards it will receive €1.2 million in funding from the Volkswagen Foundation over the course of four years, as part of the "Challenges and Potentials for Europe: Intergenerational Futures" funding line. Project lead Wanka also heads Goethe University Frankfurt's Emmy Noether Research Group "Linking Ages", which focuses on the material-discursive practices of un/doing age across the life course. 

Faced with a reality of ageing populations in all European countries, Volkswagen Foundation's funding program primarily targeted research groups that address questions of demographic change, with the stipulation that the institutions in charge of the research come from at least three different European countries. In addition to Anglia Ruskin University in the UK and Jagiellonian University in Krakow, Mönchengladbach-based Hochschule Niederrhein University of Applied Sciences is also part of the program, represented by Moritz Heß, Professor of Gerontology. A close look at Poland, for example, shows that many professional nursing staff work in western countries, especially Germany, where they earn more money. The resulting shortage of professionals at home puts even greater pressure on relatives there. 

The first phase of the study will consist of a quantitative survey in Germany: How many people are actually affected? (How) Do educational institutions address the situation? Where do rules and regulations – including compulsory attendance in laboratories and seminar rooms – make it impossible to join a course? These results will then be compared with the situation in the UK and Poland. As part of a second phase, the project foresees "dyadic interviews", in which a young person with care responsibilities and the older person being cared for are interviewed both individually and together. "The separate interviews are necessary to allow for the discussion of topics associated with shame, experiences of violence, and restrictions on freedom," says Wanka. Partly participatory in nature, those joining the project will help shape the course of the study and work together with the researchers to produce a virtual exhibition and a podcast series to raise awareness of the topic. 

Background information: 
ITVNews Coverage
BBC Coverage 

Further information
Dr. Anna Wanka
Institute for Social Pedagogy and Adult Education
Goethe University Frankfurt
Tel.: +49 (0)69 798-36411
E-Mail Wanka@em.uni-frankfurt.de
Homepage: https://www.uni-frankfurt.de/129313223/Anna_Wanka
Twitter handle/user name: WankaAnna 

Dr. Wanka may be able to facilitate interviews with study participants.

Editor: Dr. Anke Sauter, Science Editor, PR & Communication Office, Tel: +49 (0)69 798-13066, Fax: +49 (0) 69 798-763 12531, sauter@pvw.uni-frankfurt.de

FRANKFURT. The Frankfurt/Rhine-Main science region is characterized by a high density of research institutions that are already interconnected in many ways, based on common research interests and numerous cooperation agreements. To meet the major challenges of the 21st century and work together on new solutions, however, requires closer cooperation: That is why, as an initial step, 16 institutions have now joined forces and set up the Frankfurt Alliance, which is comprised of institutes from the four major scientific organizations in the Frankfurt/Rhine-Main metropolitan region, one federal institution, as well as Goethe University Frankfurt. The idea behind the network and its joint framework conditions is to create synergies and counteract the increasing segregation of work processes and research topics. 

By simplifying the conditions for joint research, reducing existing obstacles in the respective administrations by means of overarching regulations, establishing joint structures and infrastructures, and vigorously representing the interests of Frankfurt's excellent scientists in the political arena, the Frankfurt Alliance provides the framework not only for joint research, but also the transformation of scientific structures. In addition, joint activities are expected to result in closer integration between the institutions. The vision is to further develop the Frankfurt/Rhine-Main region as a leading research hub in Europe and to further increase its international standing and attractiveness for top-level research. 

Frankfurt Alliance's first joint public event will be a science festival, to be held in downtown Frankfurt on September 28, at which the participating institutions will present themselves to the public. 

Bettina Stark-Watzinger, Federal Minister of Education and Research: "I congratulate all parties involved as well as the Frankfurt/Rhine-Main region for having established the Frankfurt Alliance. In today's world, which presents us not only with great challenges but also opportunities, it is more important than ever to bundle excellence and intensify cooperation. The new science network created here holds enormous potential, and I wish it the utmost success." 

Timon Gremmels, Hessian Minister for Higher Education, Research, Science and the Arts: "Science and research are essential to mastering the transformation processes of our time and at the same time securing our democracy – something which will be all the more successful by joining forces. The Frankfurt Alliance will make the outstanding research and transfer work in Frankfurt and the Rhine-Main region even more effective and visible – whether with regard to internationalization, research infrastructures or personnel recruitment. The latter is particularly important, especially in view of increasing competition for the best scientific minds. That is why the Hessian Ministry of Higher Education, Research, Science and the Arts Culture is supporting the Frankfurt Alliance both this year and next with a total of more than €500.000." 

Mike Josef, Lord Mayor of the City of Frankfurt: "The new science network is a great initiative that many people have been waiting for. Frankfurt is an excellent science and research location – two areas with which the city must be even more closely associated. This initiative is an important step in this direction. Better networking among our science and research institutions, including at an administrative level, increases the attractiveness of the entire region, enabling us to better recruit and retain skilled workers." 

Dr. Bastian Bergerhoff, Frankfurt City Treasurer: "An extremely strong alliance has come together here, which will boost Frankfurt as a science location and promote cooperation in the region. Science is, after all, also a driving force for the economy, culture and urban society, and creates material and immaterial prosperity – which is why it plays such an important role in terms of location, too. There is great potential here, which can be leveraged even better together." 

Prof. Dr. Enrico Schleiff, President of Goethe University Frankfurt: "The Memorandum of Understanding is an important step on the path to even closer networking between the scientific institutions in Frankfurt. Together, we have the unique potential to work on the important issues of the future and enter into a productive dialog with the public. I am already looking forward to September's science festival, and am convinced that its exciting program will bring together many interested people from the Frankfurt/Rhine-Main region and beyond and convey just how great an impact science in Frankfurt has on the economy, society and the shaping of political opinions." 

The members of the Frankfurt Alliance: 

• DIPF | – Leibniz Institute for Research and Information in Education
• Leibniz Institute for Financial Research SAFE 
• Peace Research Institute Frankfurt (PRIF) 
• Senckenberg Society for Nature Research (SGN) 
• Helmholtz Centre for Heavy Ion Research (GSI) 
• Fraunhofer Institute for Translational Medicine and Pharmacology (ITMP) 
• Fraunhofer Institute for Secure Information Technology (SIT) 
• the Max Planck Institutes for Biophysics (MPIBP), Empirical Aesthetics (MPIAe), Heart & Lung Research (MPIHL), Brain Research (MPIBR), and Legal History & Legal Theory (MPILHLT) 
• Ernst Strüngmann Institute for Neuroscience (ESI) 
• Paul-Ehrlich-Institut (PEI) 
• German Cancer Consortium (DKTK) Frankfurt/Main site, German Cancer Research Center (DKFZ) 
• Goethe University Frankfurt 

Image for download: https://www.uni-frankfurt.de/148705178 

Caption: The Memorandum of Understanding of the Frankfurt Alliance was signed in the Römer Frankfurt City Hall. Photo: Peter Kiefer/Goethe University Frankfurt

Editor: Dr. Dirk Frank, Press Officer/ Deputy Press Spokesperson, PR & Communications Office, Theodor-W.-Adorno-Platz 1, 60323 Frankfurt am Main, Tel.: +49 (0)69/798-13753, frank@pvw.uni-frankfurt.de