New article provides orientation to using implementation science in policing

Evidence-based policing can help ensure practices are rooted in research

Crime and Justice Research Alliance

Since the 2020 murder by Minneapolis police of George Floyd brought nationwide calls for change amid concerns that prevailing practices were not grounded in evidence and created harm, policing has been in turmoil. Implementation science (IS) involves integrating effective and evidence-based innovations into routine practice in fields like health care. Yet despite its potential, IS—and specifically, evidence-based policing (EBP)—remain vastly understudied and unused in police settings. In a new article, researchers provide an orientation to these issues to help practitioners and researchers involved with policing integrate IS into EBP.

The article was written by researchers at Temple University, Brown University, the University of Massachusetts, RTI International, Rhode Island Hospital, and George Mason University. It is published in Police Quarterly.

“Policing is ripe for new methods to examine how to change organizations and how to assess the adoption, implementation, and sustainability of evidence-driven reforms in police settings,” says Brandon del Pozo, assistant professor of medicine and of health services, policy and practice at Brown University’s Warren Alpert Medical School, as well as a research scientist at Rhode Island Hospital, who led the study.

In this article, researchers offer agendas for integrating IS into EBP as police seek to adopt evidence-informed practices that deliver public safety, respect rights, and boost community satisfaction and trust. IS promotes the use of metrics to assess how different police practices influence various outcomes, which provides police leadership valuable data about their organization.

In the article, researchers describe the historical roots of EBP in an evidence-based approach to health care, demonstrate the commonalities that make IS as natural to policing as to medicine, and survey research on IS in policing. In addition, they adapt a conceptual model of IS to policing, present two IS frameworks available to researchers and practitioners of EBP, and introduce three types of hybrid implementation/effectiveness trials suitable for use in dynamic police settings, as well as case studies.

The article also highlights the importance of the effective de-implementation of substandard or problematic practices as a key aspect of IS and discusses how police practice that fully embraces evidence will be guided by contestable values and norms, with IS providing a way to reconcile this concern. The authors conclude with a research and practice agenda for integrating IS into EBP as police contend with calls to adopt evidence-informed practices, and they address counterinfluences in policing that hamper IS’s effectiveness.

“Evidence-based policing, which aims to identify and adopt police practices supported by scientific evidence, is frequently discussed in policing but has been slow to catch on in the United States,” explains Steven Belenko, professor of criminal justice at Temple University, who coauthored the study. Belenko is an expert whose work is promoted by the NCJA Crime and Justice Research Alliance, which is funded by the National Criminal Justice Association.

“De-escalation, procedural justice, hot spot policing, focused deterrence, and virtually any other body of evidence-based practices lend themselves to studying the constructs that ensure they can be implemented with enough fidelity to be effective and sustainable.”

The study was supported by the National Institute on Drug Abuse.

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Journal

Police Quarterly

DOI

10.1177/10986111241265290 

Article Title

Using Implementation Science to Improve Evidence-Based Policing: An Introduction for Researchers and Practitioners

Pre-arrest diversion-to-treatment programs may reduce crime, overdose deaths

Completing a six-month substance use disorder treatment in lieu of arrest and prosecution for minor crimes may reduce the risk of arrest, incarceration or fatal overdose, according to a new study

Peer-Reviewed Publication

Penn State

HERSHEY, Pa. — Pre-arrest diversion-to-treatment programs that focus on long-term treatment for substance use disorder may reduce crime recidivism, incarceration and overdose deaths, according to new study led by a research team from Penn State College of Medicine.

Diversion programs aim to connect individuals who have committed a crime to programs or services as an alternative to the criminal justice system, avoiding prosecution and arrest. The research team evaluated the Madison Area Recovery Initiative (MARI), a community-wide, law-enforcement-led program in Madison, Wisconsin. They found that people who committed non-violent, minor drug-use related crimes and who received a clinical assessment and six months of individualized treatment were less likely to be arrested, incarcerated or have a fatal overdose in the year following their initial arrest.

They published their findings in the Journal of Substance Use & Addiction Treatment.

“There are many sectors of our community, beyond clinical providers, patients and families, that are involved in or impacted by addiction and who are interested in innovative solutions,” said Aleksandra Zgierska, Jeanne L. and Thomas L. Leaman, MD, Endowed Professor at Penn State College of Medicine and lead researcher on the MARI project. “We thought that responding to drug use-related crime may serve as a point of intervention to facilitate addiction treatment, which we know is effective in improving health and lives and in reducing crime.”

The concept for MARI was born out of conversations dating back to 2015 between Zgierska and Captains Cory Nelson and Jason Freedman of the Madison Police Department (MPD) about how law enforcement can help address the opioid-related overdose epidemic and associated crime. They brought together partners, including the mayor’s office, the district and city attorneys’ offices and public health, treatment and community organizations, to design and implement the program.

“The key was to create evidence-based, community-focused practices in policing,” said Joseph Balles, retired MPD captain, who coordinated the MARI project and co-authored the paper. “We wanted to know if, instead of arresting someone, you connect them to treatment, can that have an impact?”

Unlike other diversion programs, MARI was designed to recognize that substance use disorder is a chronic disease and emphasize longer-term engagement, explained the research team. Adult residents of the local county who committed a minor, drug use-related crime were eligible to participate. In lieu of arrest and prosecution, they were referred for a clinical assessment for substance use disorder and connected to individually-tailored treatment, counseling, peer support and recovery services. The research team previously published several papers on the MARI project including the implementation of the program, also in the Journal of Substance Use & Addiction Treatment.

“This is an opportunity to get people who need it into long-term, evidence-based treatment, not just forcing them to quit ‘cold turkey,’” said Jennifer Nyland, assistant professor of neural and behavioral sciences at Penn State College of Medicine and first author on the paper. “Recovery is a long road riddled with setbacks. MARI was designed to support treatment as a pathway toward recovery rather than punishing individuals for their addiction-fueled mistakes and setbacks.”

Criminal charges were held in abeyance while participants engaged in MARI and then voided for those who completed the six-month program, keeping them off their permanent criminal record. If participants did not engage or did not complete the program, charges were filed with local prosecutors.

“Criminal charges that become part of one’s record and come up on background checks can adversely impact access to resources vital to recovery such as housing or employment,” Nyland said, explaining how MARI’s promotion of an “untarnished” criminal record could have a positive impact on long-term recovery.

The program enrolled 263 people between September 2017 and August 2020. Of these participants, 103 engaged in the program, 60 began the program but did not complete it and 100 successfully completed the six-month program.

Data on arrests, incarceration and fatal overdoses were collected for one year after initial program enrollment. During that period, those who completed MARI had a more favorable crime and overdose profile. Compared to participants who completed the program, those who did not engage or who did not complete the program were 3.9 and 3.6 times, respectively, more likely to be arrested and 10.3 and 21.0 times, respectively, to be incarcerated. Up to a year later, 5.8% of participants who did not engage and 3.3% of those who did not complete MARI had a fatal overdose compared to 2.0% of those who completed the program.

The research team also found that those participants who did not engage in MARI were more likely not to have permanent housing. While the number of women in the program was low overall, women were more likely than men not to engage in the program. Those who did not complete or engage in the program were also more likely to have a more extensive criminal record, such as a higher number of prior arrests and incarceration.

The MARI program has been a model for the U.S. Department of Justice and other cities and counties across the country. For example, in Pennsylvania, the Law Enforcement Treatment Initiative, a launched by the Pennsylvania Office of Attorney General and law enforcement in 2018 currently operates in 30 counties and has implemented principles of diversion-to-treatment emphasized in MARI. MARI was recently awarded a grant from Target and the U.S. Conference of Mayors, recognizing its innovative practices.

“When you read the evaluations, people often expressed the sentiment that, ‘I can't believe it was law enforcement that introduced me to recovery.’ That's what I'm most proud of. We went out and connected people to treatment,” Balles said.

Alice Zhang, assistant professor of family and community medicine at Penn State College of Medicine, also contributed to the paper. Other authors include current or former University of Wisconsin-Madison faculty and students: Laura Albert, Mary Henningfield, Thao Nguyen and Veronica White.

U.S. Department of Justice, Bureau of Justice Assistance funded this work.

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Journal

Journal of Substance Use and Addiction Treatment

DOI

10.1016/j.josat.2024.209458 

Method of Research

Observational study

Subject of Research

People

Article Title

Law enforcement-led, pre-arrest diversion-to-treatment may reduce crime recidivism, incarceration, and overdose deaths: Program evaluation outcomes

Article Publication Date

1-Oct-2024

 

With $5M award, NSF selects UT to lead Global Center for Sustainable Bioproducts

University of Tennessee at Knoxville

 

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Dr. Art Ragauskas

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Credit: University of Tennessee

The University of Tennessee (UT) has received a $5 million grant from the US National Science Foundation (NSF) to start tackling one of the world’s biggest scientific challenges.

UT’s award is part of the 2024 Global Centers competition, a nearly $82 million international funding collaboration among agencies in the US, Canada, Finland, Japan, the Republic of Korea (ROK), and the United Kingdom to establish research institutions known as Global Centers.

The newly established Global Centers will focus on advancing bioeconomy research to solve global challenges, whether by increasing crop resilience, converting plant matter or other biomass into fuel, or paving the way for biofoundries to scale up applications of biotechnology for societal benefit.

The program supports holistic, multidisciplinary projects that bring together international teams and the many scientific disciplines, including education and social sciences, necessary to achieve use-inspired outcomes. Each center will integrate public engagement and workforce development, paying close attention to community impacts.

While they will leverage the expertise of scientists and industry partners from all member countries, the six Global Centers are hosted at US-based institutions. In addition to the center at UT, the NSF has established two Global Centers at the University of Illinois at Urbana-Champaign; one at the University of California-Berkeley; one at Michigan State University; and one at the J. Craig Venter Institute, a nonprofit genomic research organization.

Tackling Global Challenges from Rocky Top

One of the pressing global challenges identified by the collaborating countries is to develop environmentally and economically sustainable bio-derived composites and plastics to replace petroleum and its derivatives. The Global Center for Sustainable Bioproducts (GCSB), spearheaded by UT, will address this challenge.

“In a world suffering from resource limitations, challenges due to population and GDP growth, and environmental concerns, developing a circular economy has become a key priority,” said Art Ragauskas, the interim Department Head of UT’s Department of Chemical and Biomolecular Engineering, the UT-ORNL Governor’s Chair for Biorefining, and the principal investigator of the GCSB.

“Petroleum-derived plastic products are not biodegradable and not always recyclable, leading to well-documented environmental and health problems,” Ragauskas continued. “Similarly, agricultural wastes remain largely unutilized and are burned in some parts of the world, causing substantial atmospheric pollution. Our Center is targeted at developing advanced biorefining operations to create next-generation, environmentally friendly, and economically viable polyesters from these agricultural wastes.”

Alongside Ragauskas, Hyeongmin Seo (University of Iowa), Gyu Leem and Chang Geun Yoo (State University of New York), and Clara Choi will serve as co-principal investigators. This Center will be jointly supported by the NSF, the Natural Sciences and Engineering Research Council and the Social Sciences and Humanities Research Council of Canada, the National Research Foundation of Korea, and UK Research and Innovation.

The GCSB team includes researchers and industry partners from all six member nations of the Global Center initiative, creating a diverse team that will foster innovative approaches aimed at converting and utilizing waste biomass to create bioplastics.

Ragauskas says that the NSF made the correct decision in basing the GCSB at UT, largely due to the university’s unique relationship with the agricultural sector.

“UT is at the crossroads of sustainable renewable materials, chemicals, and fuels,” he said. “Environmentally friendly research is a common theme on campus, we have numerous partnerships with ORNL on green technologies, and—perhaps most importantly—UT students are interested in pursuing green technologies that address societal challenges to make a better world.”

Part of a Worldwide Scientific Network

The Global Centers program leverages NSF’s areas of strength to advance the bioeconomy executive order and the Bold Goals for US Biotechnology and Biomanufacturing. The Global Centers will also capitalize on other NSF investments in biofoundries that enable researchers to rapidly design, create, test, and streamline the development of tools and products to accelerate research to advance the bioeconomy.

The other five Global Centers will tackle problems like crop resilience in the face of climate change and integration of biomanufacturing into global supply chains.

“Global Centers are … international centers of research excellence (that) will generate crucial knowledge, empower communities, and strengthen the foundations of global cooperation,” said NSF Director Sethuraman Panchanathan. “Together, we are forging new solutions to pressing socioeconomic challenges impacting all of us.”

GOD TOLD ME TO

What happens in the brain when a person with schizophrenia “hears voices”?

New study used brain scans of people with and without auditory hallucinations to model the brain networks that may be involved

PLOS

 

image: 

The cognitive neural mechanism of auditory hallucinations. Dissociative impairment of functional distinct signals in motor-to-sensory transformation process – a ‘broken’ monitoring signal plus a ‘noisy’ activation signal in the – causes erroneous monitoring of the imprecise generation of internal auditory representation and yields auditory hallucinations. (adapted from the manuscript.)

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Credit: Fuyin Yang and Xing Tian (CC-BY 4.0, https://creativecommons.org/licenses/by/4.0/)

Auditory hallucinations are likely the result of abnormalities in two brain processes: a “broken” corollary discharge that fails to suppress self-generated sounds, and a “noisy” efference copy that makes the brain hear these sounds more intensely than it should. That is the conclusion of a new study published October 3rd in the open-access journal PLOS Biology by Xing Tian, of New York University Shanghai, China, and colleagues.

Patients with certain mental disorders, including schizophrenia, often hear voices in the absence of sound. Patients may fail to distinguish between their own thoughts and external voices, resulting in a reduced ability to recognize thoughts as self-generated. In the new study, researchers carried out electroencephalogram (EEG) experiments measuring the brain waves of twenty patients diagnosed with schizophrenia with auditory hallucinations and twenty patients diagnosed with schizophrenia who had never experienced such hallucinations.

In general, when people are preparing to speak, their brains send a signal known as “corollary discharge” that suppresses the sound of their own voice. However, the new study showed that when patients with auditory hallucinations were preparing to speak a syllable, their brains not only failed to suppress these internal sounds, but had an enhanced “efference copy” response to internal sounds other than the planned syllable.

The authors conclude that impairments in these two processes likely contribute to auditory hallucinations and that targeting them in the future could lead to new treatments for such hallucinations.

The authors add, “People who suffer from auditory hallucinations can ‘hear’ sounds without external stimuli. A new study suggests that impaired functional connections between motor and auditory systems in the brain mediate the loss of ability to distinguish fancy from reality.”

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In your coverage, please use this URL to provide access to the freely available paper in PLOS Biology: http://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.3002836

Citation: Yang F, Zhu H, Cao X, Li H, Fang X, Yu L, et al. (2024) Impaired motor-to-sensory transformation mediates auditory hallucinations. PLoS Biol 22(9): e3002836. https://doi.org/10.1371/journal.pbio.3002836

Author Countries: China

Funding: This study was supported by the National Natural Science Foundation of China 32071099 and 32271101 (https://www.nsfc.gov.cn/), Natural Science Foundation of Shanghai 20ZR1472100 (https://svc.stcsm.sh.gov.cn/), Program of Introducing Talents of Discipline to Universities, Base B16018 to X.T., East China Normal University (ECNU) Academic Innovation Promotion Program for Excellent Doctoral Students YBNLTS2019-026 (http://www.yjsy.ecnu.edu.cn/ ) and China Postdoctoral Foundation under Grant Number 2024M752047 (https://www.chinapostdoctor.org.cn/bshjjh/) to F.Y. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

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Journal

PLoS Biology

DOI

10.1371/journal.pbio.3002836 

Method of Research

Experimental study

Subject of Research

People

 

Trauma takes its toll at the end of life

University of California - San Francisco

Clinicians should consider the impact of cumulative hardships when treating patients in their final years. 

Repeating a school year, experiencing parental abuse or engaging in armed combat have far-reaching effects on the mind and body that may extend to a person’s last months.   

These traumatic experiences can worsen the pain, depression and loneliness at the end of life, according to a study led by UC San Francisco and the University of Michigan. 

“We found that early-life trauma in particular, especially physical abuse by parents, was strongly related to end-of-life pain, loneliness and depressive symptoms,” said senior author Ashwin Kotwal, MD, of the UCSF Division of Geriatrics and the San Francisco VA Medical Center.  

“Traumatic events in childhood may have reverberating effects throughout the lifespan. They may play a role in social and emotional isolation, poor health habits and an increased risk of subsequent trauma,” he said. 

These findings emerged from the Health and Retirement Study (HRS), which followed approximately 6,500 Americans over the age of 50, who died from 2006 to 2020. It appears on Oct. 1 in the Journal of the American Geriatrics Society. 

The participants were asked to complete a questionnaire about their experiences with 11 traumatic events, as well as their psychosocial wellbeing. They were interviewed every other year until death, which occurred at an average age of 78. A final “exit interview” with a family member or friend with power of attorney provided information about symptoms in their last year.  

Trauma “gets under the skin,” according to first author Kate Duchowny, PhD, MPH, of the Institute for Social Research at the University of Michigan, where the HRS study is conducted. “We know that trauma is associated with depression and anxiety, which may promote a pro-inflammatory environment that is associated with chronic conditions. If stress is persistent, it can lead to inflammation and adverse health consequences in later life,” she said.  

Repeating a school year is common and leaves lasting mark 

The researchers found that 2 in 5 participants experienced childhood traumas, such as getting into trouble with the police and exposure to family members’ drug or alcohol abuse.  

The most common potentially traumatic event in childhood was repeating a school year. The most common causes of trauma in adulthood were a life-threatening illness, or having a spouse or child with a life-threatening illness. 

Less common were the death of a child, having a partner with drug addiction, surviving a natural disaster or engaging in armed combat. More than 80% of participants experienced at least one lifetime trauma, and 1 in 3 experienced at least three. 

Participants who reported no traumas were less likely to experience pain or loneliness when they were dying. They had a 46% probability of moderate-to-severe pain and a 12% probability of loneliness. For those who had experienced at least five traumatic events, these figures were 60% and 22%, respectively.  

Depression was also markedly lower among the participants who hadn’t experienced trauma. They had a 24% probability of end-of-life depression, versus 40% for those who had been through five or more traumatic events.  

“What this tells us as providers is that we should view a patient’s needs through a trauma lens,” said Kotwal, who is board certified in geriatrics and palliative care. “Near the end of their lives, people may experience ‘total pain’ – pain that may be spiritual and psychological, as well as pain from physical sources. Lifetime trauma may shape that total experience of pain. Connecting with a psychologist, chaplain or social worker may be what’s most effective in alleviating pain,” he said. 

“We may learn that what underlies a patient’s suffering is not only disease-related symptoms, but the ongoing anxiety and distress that comes with experiencing a loss of control over one’s body,” said co-author Chelsea K. Brown, a social worker formerly with the UCSF Division of Palliative Medicine. “For a person who has also experienced trauma, this loss of control may serve as a reminder of previous harmful experiences, and this is painful to relive in so many ways.” 

Other Authors: Alexander K. Smith, MD, MPH, Amy L. Byers, PhD, MPH, and Kristine Yaffe, MD, of UCSF and the San Francisco VA Medical Center; Irena Cenzer, PhD, and Carla Perissinotto, MD, MHS, of UCSF; and Grace Noppert, PhD, MPH, of the University of Michigan.  

Funding: National Institute on Aging (K23AG065438, P30AG044281, K24AG062785, R00AG066846, R00AG062749) and the Department of Veterans Affairs (IK6 CX002386).  

Conflicts of Interest: Kotwal and Perissinotto report consulting fees from Papa Health.  
 

About UCSF Health: UCSF Health is recognized worldwide for its innovative patient care, reflecting the latest medical knowledge, advanced technologies and pioneering research. It includes the flagship UCSF Medical Center, which is a top-ranked hospital, as well as UCSF Benioff Children’s Hospitals, with campuses in San Francisco and Oakland; Langley Porter Psychiatric Hospital; UCSF Benioff Children’s Physicians; and the UCSF Faculty Practice. These hospitals serve as the academic medical center of the University of California, San Francisco, which is world-renowned for its graduate-level health sciences education and biomedical research. UCSF Health has affiliations with hospitals and health organizations throughout the Bay Area. Visit https://www.ucsfhealth.org/. Follow UCSF Health on Facebook or on Twitter

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Follow UCSF
ucsf.edu | Facebook.com/ucsf | Twitter.com/ucsf | YouTube.com/ucsf

 

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Journal

Journal of the American Geriatrics Society

 

Robin Dunbar: Pioneering evolutionary psychologist redefines human social networks

Genomic Press Interview unveils Dunbar's journey from primate studies to groundbreaking social brain theory

Genomic Press

 

image: 

Robin Dunbar defending the future of science at the famous Speakers’ Corner in Hyde Park, London, where any member of the public is, by tradition, allowed to say anything they like, no matter how controversial or treasonous, without fear of intervention by the police or the state.

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Credit: Robin Dunbar

Oxford, UK – Genomic Press has released a captivating interview with Professor Robin Dunbar, the eminent evolutionary psychologist and anthropologist whose work has fundamentally altered our understanding of human social networks. Published in the Innovators and Ideas section of Genomic Psychiatry, this in-depth conversation offers unique insights into Professor Dunbar's scientific journey and the far-reaching implications of his research.

Professor Dunbar, best known for conceptualizing "Dunbar's number" - the cognitive limit to the number of stable social relationships an individual can maintain - traces his path from philosophy student to world-renowned scientist. "Although I went to university to study philosophy, I was quickly attracted to psychology and animal behaviour, which converted me from a humanities person to an enthusiastic scientist," he reveals in the interview.

His groundbreaking work on the social brain hypothesis, which establishes a quantitative relationship between group size and brain size across primates, has had profound implications far beyond academia. It has influenced fields as diverse as social media design and organizational management, prompting questions about how digital technologies might be reshaping our social cognitive capacities. Could the rise of online social networks be altering the fundamental constraints Professor Dunbar identified?

The interview delves into Professor Dunbar's current research focuses, which include "building a better understanding of the structural constraints that limit the size of our social world" and "achieving a better understanding of its neurobiological underpinnings." This ongoing work raises intriguing questions about the potential for neuroplasticity in social cognition. How might interventions or environmental factors influence our capacity for social relationships?

Professor Dunbar's interdisciplinary approach, spanning psychology, evolutionary biology, and anthropology, offers a model for tackling complex scientific questions. "If we try to spend time in other corners as well, that often helps us see the big picture faster," he explains, highlighting the value of cross-disciplinary collaboration in scientific discovery.

The Genomic Press Interview also offers a glimpse into Professor Dunbar's personal philosophy and motivations. When asked about his greatest achievement, he cites "Dunbar's Number," noting, "It was completely unexpected, and so, at the time, it seemed just mildly interesting. Its significance became increasingly apparent later on – mainly thanks to other people's perceptiveness." This reflection raises questions about the unpredictable nature of scientific impact. How often do seemingly minor findings turn out to be revolutionary, and what can the scientific community do to better recognize and nurture such potential breakthroughs?

Professor Dunbar's work on the neurobiological underpinnings of social behaviour opens up exciting avenues for future research. Could a deeper understanding of these mechanisms lead to novel interventions for social disorders? How might this knowledge inform strategies for maintaining social connections in an increasingly digital world?

The interview, part of Genomic Press's innovative Innovators and Ideas series, not only highlights Professor Dunbar's scientific contributions but also provides a rare personal insight into the mind of a leading researcher. By combining probing questions about scientific work with more personal inquiries inspired by the Proust Questionnaire, the interview format offers a holistic view of the scientist behind the discoveries.

As social structures continue to evolve in the digital age, Professor Dunbar's insights remain more relevant than ever. His work prompts us to consider: How can we design digital platforms that better align with our cognitive social limits? What are the implications of his theories for mental health and well-being in increasingly connected yet potentially isolated societies?

The full Genomic Press Interview, titled “Robin Dunbar: The neurobiology of human sociality,” is available on 3 October 2024 in Genomic Psychiatry, offering readers an unparalleled opportunity to explore the thoughts and experiences of one of the most influential minds in evolutionary psychology and social neuroscience. The article is freely available online at https://gp.genomicpress.com/aop/.

About Genomic Psychiatry – Genomic Psychiatry: Advancing Science from Genes to Society (ISSN: 2997-2388) represents a paradigm shift in genetics journals by interweaving advances in genomics and genetics with progress in all other areas of contemporary psychiatry. Genomic Psychiatry publishes peer-reviewed papers of the highest quality from any area within the continuum that goes from genes and molecules to neuroscience, clinical psychiatry, and public health.

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Method of Research

News article

Subject of Research

People

Article Title

Robin Dunbar: The neurobiology of human sociality

Article Publication Date

3-Oct-2024

 

Mapping the neurocircuit for the acute effects of psychedelics on anxiety

Tata Institute of Fundamental Research

 

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A Novel target for Anti-Anxiety Psychedelic drugs

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Credit: Prepared by CACTUS

Psychedelics have been used in indigenous cultures for centuries, with empirical evidence of their mood and perception altering effects. Recently, there has been a renewal of interest in psychedelics given putative therapeutic effects in psychiatric disorders such as anxiety and depression. However, it has remained a mystery as to how psychedelics actually bring about changes in mood-related behavior. A team of researchers led by Prof. Vidita Vaidya from TIFR Mumbai, in collaboration with research groups from Cornell, Columbia and Yale University mapped the precise part of the brain, and the specific class of neurons within this brain region, that drives the decrease in anxiety caused by acute treatment with the psychedelic DOI.

The psychedelic DOI when administered to rats or mice systemically, decreases anxiety behavior on approach-avoidance behavioral tasks, such as the elevated plus maze and open field test. To precisely pinpoint the part of the brain that responds to DOI and drives this decrease in anxiety behavior, local infusions of the drug into targeted brain regions uncovered a critical role of the ventral hippocampus in mediating this effect of the psychedelic DOI. Further, the study uncovered that the psychedelic DOI targets the serotonin2A receptor in the ventral hippocampus to exert its effects on anxiety. At the same time, the team also ruled out contributions from other brain regions including the prefrontal cortex and amygdala. What was striking is that the ventral hippocampus while vital for the decrease in anxiety evoked by DOI, did not contribute to hallucinations, highlighting that psychedelics target different parts of the brain to drive many behavioral changes.

Electrophysiological studies revealed that the psychedelic DOI increased the firing of parvalbumin-positive, fast-spiking, interneurons in the ventral hippocampus, which express the serotonin2A receptor. This identified the potential cellular trigger through which the psychedelic DOI may reduce anxiety behavior. To behaviorally test this, chemogenetic strategies were used to activate this particular subclass of neurons within the ventral hippocampus in the absence of the psychedelic DOI, which was sufficient to decrease anxiety behavior in animal models. Further, using a genetic knockout mouse model that lacked any serotonin2A receptor in the brain and body, selective restoration of the serotonin2A receptor on parvalbumin neurons was sufficient to reinstate the decline in anxiety that was seen on treatment with the psychedelic DOI in the ventral hippocampus.  Together, using genetic, pharmacological, electrophysiological and behavioral studies, the team identified parvalbumin-positive, fast-spiking, interneurons in the ventral hippocampus as the cellular trigger through which the psychedelic DOI can reduce anxiety.

This provides the first evidence of a clear mapping of the precise neuronal population and brain region targeted by a psychedelic to influence anxiety behavior. Since it also demonstrated that this brain circuit does not evoke altered perception and hallucinations, it opens up the intriguing possibility of using psychedelic-inspired drugs that have therapeutic potential for the treatment of anxiety disorders, whilst not exerting potent hallucinatory effects. 

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Journal

Neuron

DOI

10.1016/j.neuron.2024.08.016 

Article Title

Ventral hippocampal parvalbumin interneurons gate the acute anxiolytic action of the serotonergic psychedelic DOI