. Scientific Frontline: Psychiatry
Showing posts with label Psychiatry. Show all posts
Showing posts with label Psychiatry. Show all posts

Monday, March 4, 2024

Dopamine production is not behind vulnerability to cocaine abuse

Averaged parametric brain maps of [18F]-FDOPA kicer, and index of dopamine synthesis capacity, in high- and low-impulsive rats before and after repeated cocaine self-administration.
Image Credit: © 2024 Urueña-Méndez et al.

Why do some people who try drugs struggle with substance abuse while others don’t? This question has long puzzled scientists. A team from the University of Geneva (UNIGE) explored the complex interplay between personality traits and brain chemistry. The scientists studied the role of impulsivity and the production of dopamine – the so-called "happiness hormone" – in influencing the risk of cocaine abuse. These results, published in eNeuro, offer new keys to understanding vulnerability to drug abuse, which could lead to the development of more targeted interventions for people at risk.

When a person consumes an addictive drug, his or her dopamine release surges, creating a “high” feeling. With repeated drug use, this dopamine release drops, potentially driving the person to increase drug consumption. This mechanism varies between individuals, with some showing a greater propensity to consume the drug while others don’t. However, the reasons for these differences are unknown.

Monday, February 26, 2024

Gut-brain communication turned on its axis

How the gut communicates with the brain
Image Credit: Copilot AI

The mechanisms by which antidepressants and other emotion-focused medications work could be reconsidered due to an important new breakthrough in the understanding of how the gut communicates with the brain.

New research led by Flinders University has uncovered major developments in understanding how the gut communicates with the brain, which could have a profound impact on the make-up and use of medications such as antidepressants.

“The gut-brain axis consists of complex bidirectional neural communication pathway between the brain and the gut, which links emotional and cognitive centers of the brain,” says Professor Nick Spencer from the College of Medicine and Public Health.

“As part of the gut-brain axis, vagal sensory nerves relay a variety of signals from the gut to the brain that play an important role in mental health and wellbeing.

“The mechanisms by which vagal sensory nerve endings in the gut wall are activated has been a major mystery but remains of great interest to medical science and potential treatments for mental health and wellbeing.”

Wednesday, February 21, 2024

Sleep improves ability to recall complex events

Sleep is important for reinforcing complex associations, the basis for completing memories of entire events
Photo Credit: Shane

Researchers have known for some time that sleep consolidates our memories of facts and episodic events. However, the research to date has concentrated mainly on simple associations – that is to say, connections between elements, such as we make when learning new vocabulary. “But in real life, events are generally made up of numerous components – for example, a place, people, and objects – which are linked together in the brain,” explains Dr. Nicolas Lutz from LMU’s Institute of Medical Psychology. These associations can vary in strength and some elements might be connected with each other only indirectly. “Thanks to the neural connections that underlie these associations, a single cue word is often all it takes for somebody to recall not only individual aspects of an event but multiple aspects at once.” This process, which is known as pattern completion, is a fundamental feature of episodic memory. Lutz is lead author of a study recently published in the journal Proceedings of the National Academy of Sciences (PNAS), which investigated the effect of sleep on memory of such complex events.

Monday, February 19, 2024

Oregon State study sheds light on links between cognitive and motor skill development in children with autism

Image Credit: Aedrian

A recent study by Oregon State University researchers highlighted the ways motor skills and cognitive skills develop in connection with each other in young children with autism, and found an opportunity for behavioral and physical therapists to work together to improve care.

“We know they’re highly linked, but we often talk about them in different domains,” said study co-author Megan MacDonald, head of the School of Exercise, Sport, and Health Science in OSU’s College of Health. “When we look at wraparound services and talk about academic, social, physical and cognitive services, there’s so much we could do together.”

When assessing, diagnosing and providing services for young children with autism, providers are often siloed from each other, MacDonald said. Occupational and physical therapists focus on fine and gross motor skills, while behavioral therapists focus on emotional regulation and executive function.

But in many situations, the two sides depend on each other, she said. Fine motor skills are closely linked to cognition, such as the combination of moves kids must remember and perform in the correct order to write their name. The gross motor skills used in a playground game of kickball work in tandem with the social and emotional skills used to interact with other students and work as a team.

Tuesday, February 13, 2024

Study finds childhood bullying linked to distrust and mental health problems in adolescence

Photo Credit: Mikhail Nilov

A new study, co-led by UCLA Health and the University of Glasgow, found that young teenagers who develop a strong distrust of other people as a result of childhood bullying are substantially more likely to have significant mental health problems as they enter adulthood compared to those who do not develop interpersonal trust issues.

The study, published in the journal Nature Mental Health on Feb. 13, is believed to be the first to examine the link between peer bullying, interpersonal distrust, and the subsequent development of mental health problems, such as anxiety, depression, hyperactivity and anger. 

Researchers used data from 10,000 children in the United Kingdom who were studied for nearly two decades as part of the Millennium Cohort Study. From these data, the researchers found that adolescents who were bullied at age 11 and in turn developed greater interpersonal distrust by age 14 were around 3.5 times more likely to experience clinically significant mental health problems at age 17 compared to those who developed less distrust.

Monday, February 12, 2024

Researchers identify brain hub with key role in learned response to direct and indirect threats

Diagram of mouse prefrontal cortex showing neural projections to the midbrain (purple) and the amygdala (green), pathways involved in learning about threat.
Image Credit: National Institute on Alcohol Abuse and Alcoholism

NIH-supported study in mice could inform treatments of trauma- and stress-related psychiatric conditions.

Scientists have identified an area within the brain’s frontal cortex that may coordinate an animal’s response to potentially traumatic situations. Understanding where and how neural circuits involving the frontal cortex regulate such functions, and how such circuits could malfunction, may provide insight about their role in trauma-related and stress-related psychiatric disorders in people. The study, led by scientists at the National Institute on Alcohol Abuse and Alcoholism (NIAAA), a part of the National Institutes of Health, was published in Nature.

“Experiencing traumatic events is often at the root of trauma-related and stress-related psychiatric conditions, including alcohol use disorder (AUD),” said the study’s senior author, Andrew Holmes, Ph.D., senior investigator in NIAAA’s Laboratory of Behavioral and Genomic Neuroscience. “Additionally, witnessing others experience traumatic events can also contribute to these disorders.”

Tuesday, December 19, 2023

Enlarged Spaces in Infant Brains Linked to Higher Risk of Autism, Sleep Problems

Dea Garic, PhD, and Mark Shen, PhD, both in the UNC School of Medicine’s Department of Psychiatry, have found that enlarged perivascular spaces in the brains of babies, caused by an accumulation of excess cerebrospinal fluid, have a 2.2 times greater chance of developing autism later in life.
Photo Credit: Courtesy of University of North Carolina at Chapel Hill

Throughout the day and night, cerebrospinal fluid (CSF) pulses through small fluid-filled channels surrounding blood vessels in the brain, called perivascular spaces, to flush out neuroinflammation and other neurological waste. A disruption to this vital process can lead to neurological dysfunction, cognitive decline, or developmental delays.

For the first time, researchers Dea Garic, PhD, and Mark Shen, PhD, both at the UNC School of Medicine’s Department of Psychiatry, discovered that infants with abnormally enlarged perivascular spaces have a 2.2 times greater chance of developing autism compared to infants with the same genetic risk. Their research also indicated that enlarged perivascular spaces in infancy are associated with sleep problems seven to 10 years after diagnosis.

“These results suggest that perivascular spaces could serve as an early marker for autism,” said Garic, assistant professor of psychiatry and a member of the Carolina Institute for Developmental Disabilities (CIDD).

The researchers studied infants at increased likelihood for developing autism, because they had an older sibling with autism. They followed these infants from 6-24 months of age, before the age of autism diagnosis. Their study, published in JAMA Network Open, found that thirty percent of infants who later developed autism had enlarged perivascular spaces by 12 months. By 24 months of age, nearly half of the infants diagnosed with autism had enlarged perivascular spaces.

Thursday, November 2, 2023

Brain health in over 50s deteriorated more rapidly during the pandemic

Photo Credit: Gabriel Porras

Brain health in over 50s deteriorated more rapidly during the pandemic, even if they didn’t have COVID-19, according to major new research linking the pandemic to sustained cognitive decline.

Researchers looked at results from computerized brain function tests from more than 3,000 participants of the online PROTECT study, who were aged between 50 and 90 and based in the UK. The remote study, led by teams at the University of Exeter and the Institute of Psychiatry, Psychology & Neuroscience (IoPPN) at King’s College London, and part-funded by NIHR Maudsley BRC, tested participants’ short-term memory and ability to complete complex tasks.

Through analyzing the results from this big dataset, researchers found that cognitive decline quickened significantly in the first year of the pandemic, when they found a 50 per cent change to the rate of decline across the study group. This figure was higher in those who already had mild cognitive decline before the pandemic, according to the research published in The Lancet Healthy Longevity.

Wednesday, November 1, 2023

High metabolism is an early sign of Alzheimer’s disease

Illustration Credit: geralt

An early phase in the process of developing Alzheimer’s disease is a metabolic increase in a part of the brain called the hippocampus, report researchers from Karolinska Institutet in a study published in Molecular Psychiatry. The discovery opens up new potential methods of early intervention.

Alzheimer’s disease is the most common form of dementia and strikes about 20,000 people in Sweden every year. Researchers now show that a metabolic increase in the mitochondria, the cellular power plants, is an early indicator of the disease. 

The teams behind the study used mice that developed Alzheimer’s disease pathology in a similar way to humans. The increase in metabolism in young mice was followed by synaptic changes caused by disruption to the cellular recycling system (a process known as autophagy), a finding that was awarded the Nobel Prize in Physiology or Medicine in 2016. 

After a time, metabolism in the Alzheimer brain usually declines, which contributes to the degradation of synapses. This the researchers could also see in the older mice, which had had the disease for a longer time. 

Tuesday, October 31, 2023

New genes linked to ADHD identified potentially paving the way for new treatments

Image Credit: Braňo

Several new genes associated with conditions such as Attention-deficit hyperactivity disorder (ADHD) have been identified, unearthing a significant connection between these disorders and our immune system that could lead to new treatments. The research from the University of Surrey also confirms the role of gene ADGRL3 in conditions such as ADHD, giving scientists a greater understanding of its workings.

During this innovative study, scientists led by Dr Matt Parker from Surrey set out to understand more about ADGRL3, a gene closely linked to ADHD and other ‘externalizing’ disorders, in promoting behaviors such as substance abuse, which can be associated with the conditions. Through this work, scientists identified several new genes related to externalizing disorders, which could lead to the development of new medication to lessen the impact on individuals.

Thursday, October 26, 2023

An unexpected link between 2 schizophrenia risk proteins

The study findings suggest that when the proteins don’t bind properly, signaling among neurons, illustrated above, becomes imbalanced, which can lead to related negative behavioral symptoms.
 Image Credit: T. Ahmed, A. Buonanno, National institute of Child Health and Human Development

The discovery of a physical interaction between two proteins in brain cells that can be traced in mice to control of movement, anxiety and memory could one day open the door to development of new schizophrenia treatment strategies.

The research group is the first to determine that the two proteins, both among the dozens of proteins related to risk for the development of schizophrenia, bind to each other under normal conditions in multiple regions of the brain, and that their connection was found in mice to be key to maintaining normal movement, memory function and anxiety regulation.

When that connection doesn’t happen as it should, they found, behavior can be negatively affected – in mice, disruption to the proteins’ ability to interact increased hyperactivity, reduced risk avoidance and impaired memory. Though delusions and hallucinations are hallmark symptoms of schizophrenia, the condition also encompasses additional symptoms, including movement and memory problems. 

“These two proteins are seemingly unrelated, and our study has provided a link between them that wasn’t recognized before,” said lead author Chen Gu, associate professor of biological chemistry and pharmacology in The Ohio State University College of Medicine.  

Brain implant at OHSU successfully controls both seizures and OCD

OHSU neurosurgeon Ahmed Raslan, M.D., and patient Amber Pearson.
Photo Credit: OHSU/Christine Torres Hicks

A patient at Oregon Health & Science University is the first in the world to benefit from a single stimulator implanted in the brain to effectively control two life-altering conditions: seizures caused by epilepsy and compulsive behavior caused by obsessive-compulsive disorder, or OCD.

Amber Pearson, 34, of Albany, said her seizures are under better control, but the relief from her psychiatric condition is profound.

“OCD is worse than having the seizures,” she said. “Epilepsy brings limitations to my life, but OCD controlled it.”

In the case study, published in the journal Neuron, co-authors from institutions across the country describe the interactive programming of the responsive neurostimulation system, or RNS, that now functions seamlessly to control the compulsions that once ruled her life.

“Before I started treatment with my RNS, I would wash my hands until they would bleed,” Pearson said. “My hands would be so dry that bending my fingers would crack the skin of my knuckles.”

Wednesday, October 25, 2023

Simple blood test can help diagnose bipolar disorder

Providing a drop of blood for a test 
Photo Credit: Cambridge Centre for Neuropsychiatric Research

The researchers, from the University of Cambridge, used a combination of an online psychiatric assessment and a blood test to diagnose patients with bipolar disorder, many of whom had been misdiagnosed with major depressive disorder.

The researchers say the blood test on its own could diagnose up to 30% of patients with bipolar disorder, but that it is even more effective when combined with a digital mental health assessment.

Incorporating biomarker testing could help physicians differentiate between major depressive disorder and bipolar disorder, which have overlapping symptoms but require different pharmacological treatments.

Although the blood test is still a proof of concept, the researchers say it could be an effective complement to existing psychiatric diagnosis and could help researchers understand the biological origins of mental health conditions. The results are reported in the journal JAMA Psychiatry.

Bipolar disorder affects approximately one percent of the population – as many as 80 million people worldwide – but for nearly 40% of patients, it is misdiagnosed as a major depressive disorder.

People with severe mental illness at 50 per cent higher risk of death following COVID-19 infection

Photo Credit: Darina Belonogova

New research from King’s College London has found that people in the UK with severe mental illness were at increased risk of death from all causes following COVID-19 infection compared to those without severe mental illness.

Published in the British Journal of Psychiatry, the study investigated the extent to which having severe mental illness, which includes schizophrenia and psychosis, increased the risk of death during the first two waves of the COVID-19 pandemic.

Researchers at the Institute of Psychiatry, Psychology & Neuroscience (IoPPN) and ESRC Centre for Society and Mental Health analyzed data from over 660,000 UK patients between February 2020 and April 2021.

Among the 7146 people with severe mental illness, there was a 50 per cent greater risk of death from all causes following COVID-19 infection compared with those without severe mental illness.

Black Caribbean/Black African people were at 22 per cent higher risk of death following COVID-19 infection than White people, and this was similar for people with and without severe mental illness. However, in around 30 per cent of patient data, ethnicity was not recorded.

Tuesday, October 24, 2023

Case report shows promising results using transcranial magnetic stimulation for post-stroke ataxia

Image Credit: UCLA| Health et al. Cerebellum. October 21, 2023

In a new case report, researchers at UCLA Health describe promising results using repetitive transcranial magnetic stimulation (rTMS) in the management of post-stroke cerebellar ataxia, a debilitating condition marked by impaired coordination and balance.

Cerebellar ataxia describes a group of neurological disorders that affect coordination, balance, and control of muscle movements. It results from damage or dysfunction of the cerebellum, a part of the brain responsible for coordinating voluntary movements. Ataxia can manifest as unsteady walking, difficulties with fine motor skills, and problems with speech, among other symptoms. The severity of ataxia can vary from mild to severe, and treatments often aim to manage symptoms and improve a person's quality of life as treatment options are limited.

Writing in The Cerebellum, researchers led by Evan Hy Einstein, Department of Psychiatry & Biobehavioral Sciences at the UCLA David Geffen School of Medicine, report on the case of a 58-year-old male who had experienced a cerebellar hemorrhage approximately 12 years previously. Despite intensive rehabilitation, symptoms such as slow and unsteady gait, balance issues, and urinary incontinence persisted over the years. The patient sought consultation for potential rTMS treatment. His primary complaints focused on his slow and unsteady gait, along with challenges related to balance and stability. The decision was made to employ bilateral cerebellar rTMS, representing an innovative approach to address the condition.

Tuesday, October 17, 2023

New Research Suggests Why Males and Females Respond Differently to Social Stress

Emily Wright, researcher, in a UC Davis lab.
Photo Credit: Jerry Tsai

Women are nearly twice as likely as men to be diagnosed with an anxiety disorder, but among boys and girls the likelihood is the same. New University of California, Davis, research has identified changes in the brain during puberty that may account for differences in how women and men respond to stress.

A team of psychologists has found that testosterone is the key hormone that drives gender-based differences in responses to social stress. The study encompassed six separate experiments with mice to isolate what changes in the brain drive these differences between males and females. The study was published in the Proceedings of the National Academy of Sciences, or PNAS, today.

“This research shows how the body’s hormones shape the complex interplay between the brain’s circuitry and behavioral responses to stress,” said Brian Trainor, a professor of psychology in the College of Letters and Science at UC Davis and the study’s corresponding author.

Monday, October 16, 2023

The emotional function of dreams is not the same everywhere

The study by the UNIGE and the University of Toronto shows that there is a strong link between our socio-cultural life and the function of dreams.
Photo Credit: Maeghan Smulders

Why do we dream? A product of our brain’s neurophysiology, dreaming is a complex experience that can take on many emotional tones and simulate reality to varying degrees. As a result, there is still no clear answer to this question. A study led by the universities of Geneva (UNIGE) and Toronto, and the Geneva University Hospitals (HUG), compared the dreams of two forager communities, in Tanzania and the Democratic Republic of Congo, with those of individuals living in Europe and North America. It showed that the first two groups produced more threatening, but also more cathartic and socially-oriented dreams than the Western groups. These results, to be read in Scientific Reports, show how strong the links are between the socio-cultural environment and the function of dreams.

Dreaming is a hallucinatory experience common to all human beings. It occurs most often during the paradoxical phase of sleep, known as the Rapid Eye Movement (REM) phase. However, it can occur at any sleep stage. What are the physiological, emotional or cultural functions of dreams? Does it regulate our emotions? Does it prepare us to deal with a specific situation? Recent theories suggest that during a "functional" dream, the individual simulates more threatening and/or social situations, which would have an evolutionary advantage in promoting adapted behavior to real-life situations.

Thursday, October 12, 2023

Cannabis intoxication triggers cognitive mechanism of addiction

Photo Credit: Matthew Brodeur

New research from the Institute of Psychiatry, Psychology & Neuroscience (IoPPN) at King’s College London and the University of Oxford has found that the main component of cannabis, delta-9-tetrahydrocannabinol (THC), leads to people’s attention being more drawn to other cannabis stimuli when using the drug, which researchers suggest could underpin the cognitive mechanisms behind cannabis use disorder (CUD).

The research, published in Addiction, also found that levels of cannabidiol (CBD) typically found in cannabis had no modulating effects on the participants, despite many users believing this to be the case.

Over the course of four sessions, researchers asked 46 infrequent cannabis users (using cannabis less than once a week) to inhale a cannabis vapour containing 10mg of THC, and either 0, 10, 20, or 30mg of CBD. They were then given a task designed to measure what they focused on more when given the choice between options of images (cannabis stimuli vs neutral and food stimuli vs neutral).

Researchers found that the acute inhalation of THC resulted in people being more drawn to cannabis-related cues without explicitly liking it more.

Thursday, October 5, 2023

Cellular Atlas of Amygdala Reveals New Treatment Target for Cocaine Addiction

The study was led by co-senior authors Francesca Telese, PhD (left) and Graham McVicker, PhD (right).
Photo credit: UC San Diego Health Sciences

Researchers at University of California San Diego School of Medicine and the Salk Institute for Biological Studies have created a unique, cell-by-cell atlas of the amygdala, a small structure deep within the brain that plays a crucial role in controlling emotional responses to drugs. The findings, published October 5, 2023 in Nature Neuroscience, helped the researchers identify a potential new treatment for cocaine addiction, a disease that is poorly understood at the molecular level and has virtually no approved pharmacological treatments.

“There are some drugs that can help treat other addictions, such as those to opioids or nicotine, but there are currently no safe and effective drugs approved for cocaine addictions,” said co-senior author Francesca Telese, PhD, an associate professor in the Department of Psychiatry at UC San Diego School of Medicine. “These findings help address that problem and could also point to universal molecular mechanisms of addiction that we haven’t understood until now.”

Cocaine is a widely used illicit drug and addiction to cocaine is a major public health concern, associated with a rising number of overdose deaths and a high rate of relapse. Despite the threat cocaine addiction poses, not every person who uses cocaine develops an addiction. According to the National Institute on Drug Abuse, an estimated 4.8 million people used cocaine in 2021, while only 1.4 million people had a cocaine use disorder.

Psychedelics improve mental health, cognition in special ops veterans

The Colorado River toad (Incilius alvarius), also known as the Sonoran Desert toad, is a toad species found in northwestern Mexico and the southwestern United States. It is well known for its ability to exude toxins from glands within its skin that have psychoactive properties.
Photo Credit: Alan Schmierer
(CC0 1.0 DEED)

One treatment each of two psychedelic drugs lowered depression and anxiety and improved cognitive functioning in a sample of U.S. special operations forces veterans who sought care at a clinic in Mexico, according to a new analysis of the participants’ charts. 

The treatment included a combination of ibogaine hydrochloride, derived from the West African shrub iboga, and 5-MeO-DMT, a psychedelic substance secreted by the Colorado River toad. Both are designated as Schedule I drugs under the U.S. Controlled Substances Act.

In addition to relieving symptoms of post-traumatic stress disorder (PTSD), the combined treatment also alleviated cognitive impairment linked to traumatic brain injury – which stood out to researchers from The Ohio State University who led the chart-review analysis. Many special operations forces veterans seeking treatment for complex psychiatric symptoms do not respond to more traditional therapies. 

“What sets this group apart from some other veterans and civilians is that often, they are exposed to repeated traumatic events as a routine part of their jobs. This build-up of exposure to these difficulties seems to produce a cluster of challenges that include traumatic brain injury, which we know in and of itself predisposes people to mental health problems,” said lead author Alan Davis, associate professor and director of the Center for Psychedelic Drug Research and Education (CPDRE) in Ohio State’s College of Social Work. 

“So, the fact that we saw that there were improvements in cognitive functioning linked to brain injury were probably the most striking results, because that’s something we didn’t predict and it’s very new and novel in terms of how psychedelics might help in so many different domains.” 

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