Scientists rewrite the rules of swarming locusts

University of Konstanz

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Locust outbreak in East Africa

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Credit: Copyright: Einat Couzin-Fuchs, Inga Petelski, Yannick Günzel, Felix B. Oberhauser

Desert locusts, a notorious Biblical pest, form some of the largest insect groups in nature and are estimated to threaten the livelihood of one in ten people due to their impact on food security. Swarms begin when flightless juveniles aggregate and start marching in unison. Understanding how these plague insects coordinate their motion is crucial for developing evidence-based control, such as forecasting swarm movements. In addition, revealing the nature of inter-individual interactions is key to understanding how collective motion emerges among social animal species more broadly.

• A video can be found here: https://youtu.be/oBJnY4HKmeY

For decades, a principle borrowed from theoretical physics – treating individuals as "self-propelled particles" – has been used to model collective motion in animals. Similar to particles in physical systems like magnets, this hypothesis assumes that animals actively align with one another. However, unlike in magnets, these "particles" are constantly in motion. Such models have shown that even when individuals align only with their local neighbors, large-scale coherent movement can emerge, with vast numbers of individuals moving in the same direction.

The longstanding hypothesis also states that the density between the animals is a decisive factor for the change from non-coherent motion – where individuals move in random directions – to coherent large scale collective motion. When enough animals come together in a space, they are predicted to spontaneously transition from disordered to ordered swarm motion. This prediction was later seemingly corroborated by laboratory experiments with large locust groups, thereby strengthening the claims of these classical models.

Testing long-held hypotheses
Through a combination of fieldwork during East Africa’s locust outbreak of 2020, laboratory studies, virtual reality experiments, and a reevaluation of past data, researchers from the Cluster of Excellence "Collective Behaviour" at the University of Konstanz have concluded that the behavioural mechanisms governing collective motion in locust swarms cannot be explained by these classical models. Their findings challenge the traditional view by which collective motion is thought to emerge in animal groups.

"Inferring the mechanism of interaction in mobile animal groups is notoriously difficult", says Professor Iain Couzin, the study’s senior author, noting that "individuals both influence, and are influenced, by the behaviour of others in a complex interplay." To overcome this challenge, the Konstanz team leveraged immersive 3D virtual reality, enabling them to study how freely moving locusts interact with a computer-generated "holographic" virtual swarm. "This approach allowed us to rigorously test hypotheses about what drives their behaviour in ways that would be impossible in natural swarms", adds first author Dr Sercan Sayin.

The precise control of visual information afforded by virtual reality meant that the researchers could establish how sensory input is translated into movement decisions by locusts. Contrary to previous assumptions, the team observed that the "optomotor response" – an innate reflex in which locusts (and many other species) follow motion cues – is not responsible for coordinating collective motion. Indeed, they found no evidence that locusts explicitly align with the direction of motion of others at all.

In one virtual reality experiment, for example, focal locusts were placed in between two virtual swarms, one to their left and one to their right, both moving in the same direction. Classical models predict that under such circumstances, locusts should "go with the flow". However, the Konstanz team saw that locusts would turn to face one swarm, or the other, and move towards it.

Furthermore, the researchers found that group order is not simply a product of increasing density, as was previously thought. Alignment occurred in response to coherent visual cues, almost entirely independent of density. "It’s really about the quality of information, not the quantity", says Sercan Sayin. A reanalysis of a large number of previous laboratory experiments, which had argued for density-dependent transition to coherent motion, confirmed the Konstanz team’s findings, challenging previous assumptions about the behavioural mechanisms underlying swarming in locusts.

A new cognitive framework for collectives
In order to explain their results, it was necessary for the Konstanz team to rethink the approach of modeling collectives from the bottom up. "Locusts are not behaving like simple particles that align with one another", says Iain Couzin. "We realized that we need to model them as cognitive agents – processing their surroundings and making decisions about where to move next."

The research team developed a simple cognitive model, informed by the neurobiology of the neural circuits used by animals for spatial navigation, termed a "ring attractor" neural network. In this model, individuals have a simple neural representation of the bearing towards, but not the body orientation or direction of motion, of neighbours. Movement decisions emerge through a dynamic process in which neural representations compete or converge based on relative positioning, ultimately reaching a consensus that determines the direction of motion. "Our model is based on known neurobiological principles", explains Dr. Sayin, "and we found it can account for all of our key experimental findings".

The study, published in Science, represents nothing less than a paradigm shift in swarm research. By providing fundamental new insights into how locust behaviour results in devastating swarms, the Konstanz research may provide critical knowledge for improved locust control strategies, such as for effective modeling of swarm movement.

Moreover, the consequences of these findings will likely extend beyond locusts to broader applications in understanding the coordination of motion in other species, as well as robotics, artificial intelligence and the study of collective intelligence. Swarm robotics and autonomous vehicle coordination, for example, may benefit from algorithms inspired by locusts’ highly effective cognitive strategies for collective motion.

 

Key facts: Original publication: Sercan Sayin, Einat Couzin-Fuchs, Inga Petelski, Yannick Günzel, Mohammad Salahshour, Chi-Yu Lee, Jacob M. Graving, Liang Li, Oliver Deussen, Gregory A. Sword & Iain D. Couzin, The behavioral mechanisms governing collective motion in swarming locusts, Science387,995-1000(2025). DOI:10.1126/science.adq7832 Link: https://www.science.org/doi/10.1126/science.adq7832 This study was conducted by researchers in the Cluster of Excellence "Collective Behaviour" and the Max Planck Institute of Animal Behavior (MPI-AB). Iain D. Couzin is speaker of the Cluster of Excellence "Collective Behaviour", professor of biodiversity and collective behaviour at the University of Konstanz and director of the Max Planck Institute of Animal Behavior (MPI-AB). Sercan Sayin is a postdoctoral researcher in the Cluster of Excellence "Collective Behaviour" at the University of Konstanz.

Note to editors:
A video can be found here:
https://youtu.be/oBJnY4HKmeY

You can download photos here:

1. https://www.uni-konstanz.de/fileadmin/pi/fileserver/2025_extra/scientists_rewrite_1.jpeg

2. https://www.uni-konstanz.de/fileadmin/pi/fileserver/2025_extra/scientists_rewrite_2.jpeg

3. https://www.uni-konstanz.de/fileadmin/pi/fileserver/2025_extra/scientists_rewrite_3.jpg

Caption: Locust outbreak in East Africa
Copyright: Einat Couzin-Fuchs, Inga Petelski, Yannick Günzel, Felix B. Oberhauser
 

4. https://www.uni-konstanz.de/fileadmin/pi/fileserver/2025_extra/scientists_rewrite_4.jpg

Caption: Laboratory study with locust in the Imaging Hangar, University of Konstanz
Copyright: Christian Ziegler, Max Planck Institute of Animal Behavior (MPI-AB)

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Journal

Science

DOI

10.1126/science.adq7832 

 

Studying locusts in virtual reality challenges models of collective behavior

Summary author: Walter Beckwith

American Association for the Advancement of Science (AAAS)

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A study of locusts navigating in a novel virtual reality (VR) environment challenges traditional models of collective swarming behavior, researchers report. The findings show that the insects don’t just follow their neighbors like self-propelled particles but instead rely on internal cognitive decision-making processes to navigate as a collective. Collective motion, a phenomenon found widely in nature, has traditionally been described using "self-propelled particle" theoretical models from physics. These “classical” models of collective behavior, like the highly influential Vicsek model, explain how basic local interactions, where individuals align and synchronize their movements with those of nearby members, can give rise to large-scale, coordinated motion within groups. Desert locust (Schistocerca gregaria) swarms, which can cover vast areas and contain billions of individuals, serve as a prominent example of collective motion in nature. Using a combination of field experiments and an innovative virtual reality (VR) system in which locust nymphs moved freely, interacting with virtual locusts, while immersed in a 3D virtual environment, Sercan Sayin and collogues show that classical models of collective behavior fail to explain the motion exhibited by swarming locusts. Sayin et al. found that locusts do not follow the fixed interaction rules assumed by traditional models, such as explicitly aligning with their moving neighbors when the density of the swarm increases. Instead, locusts behaved as if they were drawn toward other locusts – a behavior that aligns with a minimal cognitive model of spatiotemporal decision-making where an individual makes directional choices based on their own internal consensus. “Sayin et al. conclude that it is time to move beyond the conception of locusts and other organisms as moving particles behaving according to fixed spatiotemporal rules and to consider organisms as probabilistic decision-makers responding dynamically to their sensory environment,” write Camille Buhl and Stephen Simpson in a related Perspective.

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Journal

Science

DOI

10.1126/science.adq7832 

Article Title

The behavioral mechanisms governing collective motion in swarming locusts

Article Publication Date

28-Feb-2025

Consequences of overplanting rootworm-resistant maize in the US Corn Belt

Summary author: Walter Beckwith

American Association for the Advancement of Science (AAAS)

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Widespread use of genetically engineered Bt maize, designed to combat rootworm pests, has led to overplanting and pest resistance, jeopardizing the crop’s long-term effectiveness, according to a new study. The findings – informed by data from ten U.S. “Corn Belt” states – estimate that this overuse has cost U.S. farmers $1.6 billion in economic losses, emphasizing the need for improved seed diversity, transparency, and farmer decision-making to sustain transgenic crop benefits. “If current and future related innovations are managed as Bt maize hybrids have been,” say the authors, “we risk entering a cycle of rapid obsolescence among transgenic technologies…” Genetically engineered crops, particularly those incorporating insecticidal proteins from Bacillus thuringiensis (Bt), have significantly boosted global food production by reducing pest damage with minimal environmental impact. However, as the use of Bt crops increases, pests inevitably develop resistance, diminishing the effectiveness of the technology over time. Bt maize hybrids targeting corn rootworms have seen widespread use, but resistance began emerging in 2009, raising concerns about Bt maize’s long-term viability. The issue can be likened to the "tragedy of the commons," where individual actions based on self-interest lead to the overexploitation of a shared resource.

 

Leveraging 12 years of field trial data and farmers’ seed usage across 10 U.S. Corn Belt states, as well as an interdisciplinary approach distinguishing between self-interested decision-making and optical decisions that account for broader community impacts, Ziwei Ye and colleagues evaluated the economic consequences of diverging from optimal rootworm Bt maize planting levels. Ye et al. found that while pest pressure decreased as a result of pest suppression by Bt maize, increased planting of this crop has undermined its anti-rootworm effectiveness. Moreover, a cost-benefit analysis from 2014 to 2016 shows that Bt maize was often planted excessively, particularly in the eastern Corn Belt states, where pest pressure was low. This overuse led to minimal pest suppression benefits, higher costs for transgenic seed, and a significant depletion of the pest susceptibility pool, resulting in an estimated $1.6 billion in lifetime economic losses for growers in these regions. According to the authors, the findings highlight broader systemic issues driving Bt overuse. Discrepancies between planting for self-interests and the optical Bt planting levels are largely due to misperceptions about the overall costs and benefits of Bt maize. This is further complicated by bundled trait packages and market pressures from profit-driven seed companies. What’s more, farmers are often underinformed about rootworm pressures and the long-term implications of using Bt hybrids. “Addressing the challenges faced by regulators and raised by Ye et al. will require balancing short-term farmer incentives with long-term agricultural and environmental sustainability, ensuring that Bt crops remain viable tools for pest management,” write Zachary Brown and Dominic Reisig in a related Policy Forum.

 

Podcast: A segment of Science's weekly podcast with Christian Krupke, related to this research, will be available on the Science.org podcast landing page after the embargo lifts. Reporters are free to make use of the segments for broadcast purposes and/or quote from them – with appropriate attribution (i.e., cite "Science podcast"). Please note that the file itself should not be posted to any other Web site.

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Journal

Science

DOI

10.1126/science.adm7634 

Article Title

Too much of a good thing: lessons from compromised rootworm Bt maize in the US Corn Belt

Article Publication Date

28-Feb-2025

Midwestern field trials suggest overuse of rootworm-resistant corn reduces farmers’ profits

Rootworms show increasing resistance to genetically engineered corn 

Purdue University

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Corn that has been genetically engineered to resist corn rootworms like this one has become increasingly less effective. Purdue University entomologist Christian Krupke and his colleagues at 12 universities publish a multi-state analysis of the problem in the journal Science.

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Credit: John Obermeyer/Purdue University Extension Entomology

Midwestern field trials suggest overuse of rootworm-resistant corn reduces farmers’ profits

Researchers advocate new approach for managing innovative hybrid technologies

WEST LAFAYETTE, Ind. – An analysis of data covering 12 years and 10 U.S. Corn Belt states reveals that farmers suffer economic loss from the overapplication of genetically engineered corn designed to combat rootworm pests. 

The project, led by Purdue University entomologist Christian Krupke, documented greater rootworm pest pressure in the western Corn Belt states of Illinois, Iowa, Minnesota, Nebraska, North Dakota, South Dakota and Wisconsin. In these states, farmers commonly plant corn continuously. In the eastern states Corn Belt states of Indiana, Michigan and Ohio, farmers  practice crop rotation that reduces the need for control through genetically engineered seed or applied insecticides. However, the use of transgenic corn hybrids targeting rootworm pests has been remarkably similar across the entire region. This study explored the consequences of this disconnect.  

Krupke, Dean’s Fellow and professor of entomology, and 19 co-authors from 12 other universities in the U.S., China and Canada reported their results in the journal Science. The retrospective study demonstrated that the pest landscape has fundamentally changed in many key corn-growing areas of the U.S. since 2004, the initial year of broad adoption of transgenic corn hybrids targeting corn rootworms. The study shows pest pressures in much of the region declined dramatically following introduction of these hybrids, reducing the need for broad deployment of the rootworm-specific traits. 

“This study shows the value of long term, applied research datasets from public sector field research,” said Krupke. The short duration and shifting priorities of research funding streams make it increasingly rare to have such scope and coverage in biological data. “These are among the most useful types of data for developing policy recommendations,” Krupke said.

In 2003, the first genetically engineered corn hybrid trait lethal to corn rootworms and derived from the bacterium Bacillus thuringiensis (Bt) was introduced. Since then, farmers have extensively used “Bt corn” hybrids. Subsequently, multiple field studies have reported Bt resistance in rootworms since 2009, raising doubts about the long-term viability of the Bt traits.

The study emerged from observations made by a working group of corn entomologists who meet annually to discuss the impact of pests on the commodity. Several years ago, Krupke noticed a difference between corn rootworm reports in the eastern and western Corn Belt states.

“We were all in different regions of the country, yet doing much the same thing,” Krupke said. “We were still managing the pest using Bt hybrids as if rootworm was a prime driver of yield loss in states like Indiana. It wasn’t and it hadn’t been for some time.”

From 2014 to 2016, yield losses attributed to rootworm damage amounted to 47.5 bushels per acre in western states, and 8.5 bushels per acre in eastern states, the researchers estimated. 

The study quantified the two costs of using the Bt hybrid. One cost was the substantial technology fee, a premium growers pay when buying the seed. The other cost was the erosion of pest susceptibility to the Bt toxin.

“If you think of a Bt hybrid as a finite resource, like a declining debit card, every time you use it, you erode a little bit of susceptibility” Krupke said. “So it’s a little less likely that it will work as well next time.”

For their part, growers select elite hybrid seed genetics that will produce the best yields. Those hybrids often bundle a variety of other desirable traits, including expression of multiple Bt toxins, whether they are needed or not.

Christina DiFonzo, the field crops entomologist at Michigan State University, compared bundling seed traits to the packages formerly offered for cable TV. Consumers paid for hundreds of channels when they only wanted 10 or 15. Streaming services and on-demand programming has ended all that. “Farmers would welcome a similar ‘pick list’ for the seed supply and that would help insect resistance management.”

The key difference is that insect-resistant corn carries an ongoing collateral price to pay along with out-of-pocket costs. “Money can be replaced but loss of susceptibility to the technology only goes in one direction and is irreversible,” DiFonzo said.

These lessons should be applied to as-yet undefined new transgenic trait technologies for in-plant protection, said the study’s lead author, Ziwei Ye, assistant professor at the School of Agricultural Economics and Rural Development at Renmin University of China. She advised against going back to insecticides, such as organophosphates and pyrethroids, for rootworm control.

“The Bt technology is and was a net benefit that helps safeguard beneficial organisms and soil ecosystems and enhance drought tolerance,” Ye said. “These are increasingly appreciated as key resources in feeding the growing world population as our climate changes.”

Bt and antibiotics are both examples of the “biological commons.” Individuals may perceive that it makes sense to use them as insurance, even when risk of harm from the pest seems limited. If many growers do this over a long period, resistance will set in and the technology’s decline will affect them all.

“Overusing Bt may make sense for each individual, but all will eventually lose the technology sooner than might have been the case,” said study co-author David Hennessy, the Cargill Professor in Economic Systems at Iowa State University. “Essentially, each individual does not take account of the harm done to others due to the buildup of genetic resistance to the toxin.”

Farmers thus have tended to use too much of Bt seed targeting rootworms for their bottom-line profit, especially in the eastern Corn Belt.

“In many cases, they overuse the input not just for the common good but also for their own private benefit,” said ISU’s Hennessy. Simply alerting farmers to focus on comparing the financial costs and benefits to themselves when using the rootworm Bt trait might help protect the trait’s future effectiveness.

The use of transgenic technologies such as Bt maize as a key pest-management tool is likely to continue, Krupke noted. The technology is both user-friendly for growers and reduces insecticide applications.

“To keep this and future, similar technologies around and functional for the long-term is in everyone’s best interest,” he said.

This work was supported by the State Agricultural Experiment Station (SAES) from the Hatch Multistate Research Fund provided by the National Institute for Food and Agriculture (NIFA  Project NC246: Ecology and Management of Arthropods in Corn) and the National Natural Science Foundation of China.

Writer: Steve Koppes

About Purdue Agriculture

Purdue University’s College of Agriculture is one of the world’s leading colleges of agricultural, food, life and natural resource sciences. The college is committed to preparing students to make a difference in whatever careers they pursue; stretching the frontiers of science to discover solutions to some of our most pressing global, regional and local challenges; and, through Purdue Extension and other engagement programs, educating the people of Indiana, the nation and the world to improve their lives and livelihoods. To learn more about Purdue Agriculture, visit this site.

About Purdue University

Purdue University is a public research university leading with excellence at scale. Ranked among top 10 public universities in the United States, Purdue discovers, disseminates and deploys knowledge with a quality and at a scale second to none. More than 107,000 students study at Purdue across multiple campuses, locations and modalities, including more than 58,000 at our main campus in West Lafayette and Indianapolis. Committed to affordability and accessibility, Purdue’s main campus has frozen tuition 13 years in a row. See how Purdue never stops in the persistent pursuit of the next giant leap — including its comprehensive urban expansion, the Mitch Daniels School of Business, Purdue Computes and the One Health initiative — at https://www.purdue.edu/president/strategic-initiatives.

Corn that has been genetically engineered to resist corn rootworms like this one has become increasingly less effective. Purdue University entomologist Christian Krupke and his colleagues at 12 universities publish a multi-state analysis of the problem in the journal Science.

Example of the damage that corn rootworms inflict on crops. The rootworm has caused more economic losses in western U.S. Corn Belt states, according to a new Purdue-led study.

Corn rootworm larva posed on a finger for scale. Planting rootworm-resistant corn when unwarranted has led to economic loss for farmers.

Credit

John Obermeyer/Purdue University Extension Entomology

Journal

Science

DOI

10.1126/science.adm7634 

Method of Research

Experimental study

Subject of Research

Not applicable

Article Title

Too much of a good thing: lessons from compromised rootworm Bt maize in the US Corn Belt

Article Publication Date

28-Feb-2025

 

Discovery of a common ‘weapon’ used by disease-causing fungi could help engineer more resilient food crops

Australian National University

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The discovery of a powerful “weapon” used by many disease-causing fungi to infect and destroy major food crop staples, such as rice and corn, could offer new strategies to bolster global food security, according to researchers from The Australian National University (ANU) in collaboration with scientists in Germany and the United States. 

Like humans, many fungi rely on plants as a food source. This impacts the yield of food crops. It’s estimated farmers lose between 10 to 23 per cent of their crops to fungal disease every year. 

The global research team discovered that an enzyme known as a ‘NUDIX hydrolase’ is used by many fungal pathogens as a weapon to cause disease in plants. The findings are published in Science. 

By uncovering the role this enzyme plays in infecting plants, the researchers believe they can engineer more resilient rice crops, as well as other fruit and vegetable crops, capable of safeguarding themselves against disease. 

The findings could help bolster food security in nations where rice and corn are major commodities. According to the US Department of Agriculture, rice is the primary staple food for more than half of the world's population. 

Lead author Dr Carl McCombe, who completed this work as part of his PhD at ANU, said the disease-causing enzyme can infiltrate plant cells and attack a key signalling molecule involved in the sensing of phosphate – a vital nutrient necessary for plant survival. 

He said the enzyme “hijacks” key molecular pathways and tricks the plant into thinking it has a shortage of phosphate, activating a starvation-like response in the plant. This allows the pathogen to evade the immune system’s natural defence mechanisms and cause disease in the crop. 

“In collaboration with colleagues at the Australian Nuclear Science and Technology Organisation, we were able to reveal the structure of the enzyme in detail using a technique called X-ray crystallography,” Dr McCombe, who is now a postdoctoral researcher at the California Institute of Technology (Caltech), said. 

“Understanding what the enzyme looks like gave us critical insights into how it is used by pathogens to attack plants.” 

Associate Professor Simon Williams, who led the ANU research team’s contribution to this work, said in addition to engineering new crops with a turbocharged immune system, the research findings could also help scientists uncover new ways to deactivate the “hijacking effect” of the enzyme, similar to turning it on and off like a light switch. 

“Much of our work focused on the pathogenic fungus Magnaporthe oryzae, which causes rice blast disease. Rice is a critically important food staple, and losses from rice blast could feed 60 million people each year,” Associate Professor Williams said. 

“Our research also reveals that the NUDIX hydrolase is used as a ‘weapon’ by many different fungi, including ones that are responsible for causing anthracnose disease in fruit, vegetable and seed crops. These diseases impact crop production in foods such as mangoes, melons, corn and chickpeas – produce that Australians enjoy daily. 

“This suggests our work also has implications to safeguard other important fruit and vegetable staples.” 

Associate Professor Williams said the findings offer a roadmap to develop new disease management strategies. 

“This could involve engineering the plant’s immune system to detect the enzyme or block its function. This could help farmers protect their crops and secure global food supplies,” he said. 

This work involved scientists from ANU, RWTH Aachen University and Louisiana State University.  

Images available to download here. 

Photo credit: Jamie Kidston/ANU 

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Journal

Science

DOI

10.1126/science.adl5764 

Article Title

Plant pathogenic fungi hijack phosphate signaling with conserved enzymatic effectors

Article Publication Date

27-Feb-2025

 

$4.9 million grant enables test of psychedelic MDMA as enhancement for PTSD therapy

University of Texas Health Science Center at San Antonio

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SAN ANTONIO, Feb. 27, 2025 – Researchers at The University of Texas Health Science Center at San Antonio and their collaborators at Emory University have received a $4.9 million grant aimed at significantly improving treatment and recovery rates for individuals suffering from post-traumatic stress disorder.

The project was recently selected for funding by the U.S. Department of Defense through a call for studies to evaluate psychedelics as a treatment for PTSD in hopes of pushing the field forward. In this effort, the innovative clinical trial will use 3,4-methylenedioxy-methamphetamine hydrochloride, or MDMA, commonly known as ecstasy, in combination with a leading psychotherapy for PTSD called Prolonged Exposure.

Prolonged Exposure therapy for PTSD works by helping individuals process traumatic memories and feelings while recalling them in a safe environment. The goal of the new study is to capitalize on beneficial MDMA properties in a synergistic way to enhance Prolonged Exposure’s efficacy, hopefully leading to greater symptom reductions and more patients being treated into remission.

The trial’s lead investigator is Alan Peterson, PhD, professor of psychiatry and behavioral sciences at UT Health San Antonio and director of the STRONG STAR Consortium. STRONG STAR is a national research network focused on finding the best preventions and treatments for psychological health issues affecting military members, veterans, and first responders.

“Cognitive-behavioral psychotherapies have the strongest scientific support for the treatment of PTSD, but for military service members and veterans, recovery rates with these treatments seem to have maximized at about 50%,” Peterson said. “Existing medications have not shown good promise when used alone, so we’re looking at novel ways to enhance treatment outcomes so that more of our psychologically wounded warfighters have the chance of full recovery from PTSD.”

Researchers believe MDMA shows some of the greatest potential in this regard. One reason is that MDMA, in combination with psychotherapy, has demonstrated significant improvements in PTSD. It has revealed increased neuroplasticity, or the brain’s ability to adapt, for about two weeks after administration, which is beneficial for therapeutic learning.

Finally, it impacts emotional memory circuits related to PTSD development and recovery. These memory circuits affect conditioned fear responses that are associated with PTSD. Researchers think MDMA will work synergistically with Prolonged Exposure to help patients process traumatic memories.

Other research support for MDMA comes from study collaborators at Emory University School of Medicine, who include Jessica Maples-Keller, PhD, Barbara Rothbaum, PhD, and Boadie Dunlop, MD.

In an ongoing, open-label pilot study by the Emory Healthcare Veterans Program, results show that one dose of MDMA significantly reduces PTSD symptoms among military members and veterans when combined with massed Prolonged Exposure (PE). In massed PE, therapy is delivered daily for two weeks instead of the standard once or twice weekly over several weeks or months, coinciding with the timeline of MDMA’s therapeutic effects on neuroplasticity.

With this in mind, Peterson and his colleagues designed the new STRONG STAR trial to incorporate a single dose of MDMA early in treatment with massed PE. This two-armed, double-blind, randomized clinical trial will involve 100 active-duty military, guard and reserve personnel, including 75 recruited through UT Health San Antonio and 25 through Emory University School of Medicine.

After a first therapy session, a single dose of MDMA will be given in the second session, with therapeutic guidance from two therapists. Between the two study arms, the dosage level will differ to help researchers determine the optimal dose for therapeutic benefit while maintaining the study blind. The remaining sessions will be massed PE as usual, delivered during the two-week period that MDMA theoretically enhances neuroplasticity.

Participants will be assessed at one and three months post-treatment. Researchers expect that those receiving treatment will achieve significant reductions in PTSD symptoms, suicidal ideation and depression as well as significant increases in return-to-duty readiness, psychosocial functioning and intimate relationship functioning. 

Researchers say if the treatment approach is successful, it could have a profound impact on optimizing PTSD treatment for military personnel, with a strong potential to treat service members into remission. Furthermore, it could be readily disseminated within the military and VA health care systems, where PE availability is widespread and massed PE is being rolled out as a standard of care, providing opportunity for incorporating a single MDMA dose into treatment. Other possibilities could include MDMA’s incorporation into intensive outpatient treatment programs.

“We truly believe this trial provides the opportunity to make major leaps forward in PTSD treatment and potentially create a new standard of care for the field,” Peterson said.
 

 

 

 

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The STRONG STAR Consortium is a state and federally funded, multi-institutional research group working to develop and evaluate the most effective early interventions possible for the prevention, detection, diagnosis, and treatment of psychological health conditions in military personnel, veterans, and first responders. Under the leadership of The University of Texas Health Science Center at San Antonio and based in South/Central Texas, STRONG STAR brings together the expertise of a world-class team of military, civilian and VA institutions and investigators and one of the largest populations of post-9/11 military service members and veterans in the nation. With the critical mass of talent required to make major scientific advances in psychological health, STRONG STAR investigators are working to improve countless lives by preventing the development of chronic psychological health problems in military personnel, veterans, first responders, and their families.  For more information, visit https://www.strongstar.org/.