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Dr. Bridget Callaghan

Dr. Bridget Callaghan's journey into the world of mental health and child development is as intriguing as it is inspiring. While her academic journey began in Australia with an intention to join the police force, she quickly realized that her true passion lay elsewhere. This realization led her to delve into social work, where she spent a year as an undergraduate. However, her insatiable curiosity and desire to make a tangible difference led her further into the realm of psychology.

Dr. Callaghan's transition was not without its challenges. She recalls an unexpected twist during her psychology degree, where she found herself in a course centered on animal research. As a vegetarian, she was initially hesitant. But an inspiring lecturer, who would later become her PhD advisor, changed her perspective. This course set her on a path to studying rats and exploring animal models of early life adversity and its impacts on brain development.

Today, Dr. Callaghan is the recipient of numerous awards, including a K-99 Pathway to Independence Award from the National Institute for Mental Health, the Kucharski Young Investigator Award from the International Society for Developmental Psychobiology, as well as a Young Investigator Grant from the Brain Behavioral Research Foundation. Her work reaches a broad audience as she strives to create better mental and physical health treatments across development that are informed by psychological functioning, trauma history and central and peripheral biology.

The Brain and Body Lab at UCLA

In 2019, Dr. Callaghan established the Brain and Body Lab, affectionately known as the "Bab Lab", at UCLA. This lab focuses on the intricate relationship between mental and physical health and how it unfolds across development. Dr. Callaghan's team conducts studies on participants ranging from toddlers to adults, examining the intergenerational effects of experiences.

One of the lab's primary interests is the brain-gut axis. Dr. Callaghan and her team explore how gastrointestinal microbes influence brain function and how early life adversities can impact this relationship. Her research examines how early-life experiences influence interactions between physical and mental health across the lifespan. As both a clinically-trained psychologist and a basic science researcher, Dr. Callaghan performs interdisciplinary research linking physical and emotional health in children who experience extreme psychosocial deprivation due to institutionalized care, children who have experienced out of home (e.g., foster care) placements within the United States, and youth who have experienced physical illnesses in early life. Her work has been highlighted as some of the first evidence linking disruption of a child’s gut microbiome with activity in brain regions associated with emotional health.

In her Brain and Body Lab, Dr. Callaghan and her group take a multi-faceted approach toward examining the effects of early-life adversity. Research methods including studying behaviors related to emotion and memory development, observing activation of underlying neural systems using fMRI, characterizing the gut microbiome using gene sequencing, evaluating basic physiological health (using e.g., gastric function, heart rate, skin conductance), and exploring the role of parental scaffolding in healthy emotional development.

The Power of Diet and Microbiomes

Dr. Callaghan's research has illuminated the profound impact of diet on our mental and physical health. She emphasizes the importance of viewing ourselves as a "holobiont" – an ecosystem that includes not just our human cells but also the myriad of microbes that reside within us. These microbes play a pivotal role in our overall health, and our diet directly influences their composition and function.

In her interactions with parents and families, Dr. Callaghan often discusses the significance of the microbiome. She notes that many parents find solace in understanding the link between gastrointestinal health and mental well-being. This connection offers hope, suggesting multiple intervention points to improve overall health.

Dr. Callaghan's enthusiasm is palpable when she speaks about the human microbiome. "There are multiple sequencing technologies with the microbiome," she explains. From identifying bacterial distributions to the more advanced shotgun sequencing, her team is at the forefront of understanding the genetic potential of our gut microbes.

Her most recent grant proposal aims to delve even deeper, seeking to understand the actual functional output of these microbes. How do they influence our health, both mental and physical? And more importantly, how does this relate to children's behavior?

The Evolution of MRI Technology in Brain Research

"MRI technology is ever-changing," Dr. Callaghan notes. Over the years, she has witnessed and leveraged the advancements in MRI scanning to gain deeper insights into brain development. Beyond the hardware, analytical innovations are continually emerging, offering researchers like Dr. Callaghan novel ways to interpret imaging data.

One such innovation she mentions is the ability to use standard MRI scans to gauge tissue iron levels, providing indirect insights into dopamine levels in the brain. This kind of innovation is a testament to the rapid evolution of technology in the field of neuroscience.

Challenges in the Lab: The Human Element

Despite the technological advancements, Dr. Callaghan emphasizes the challenges of working with human subjects, especially children. From the variability in participation to the unique backgrounds of each child, collecting data is a meticulous and often unpredictable process.

Yet, it's clear that Dr. Callaghan is driven by more than just scientific curiosity. Behind every data point is a child, a family, a story. "It's about honoring the time and effort that families have spent contributing to the dataset," she says.

A Message of Hope and Resilience

Dr. Callaghan's collaboration with the Sydney Children's Hospital stands out as a testament to the interdisciplinary nature of her work. Applying her understanding of adversity, she has worked with children diagnosed with congenital heart disease, offering a fresh perspective on their challenges and resilience.

To families and individuals grappling with mental and physical health challenges, Dr. Callaghan offers a message of hope. "There is hope," she emphasizes. "The fact that our physical and mental health are intertwined is a good thing because it means we have multiple points of intervention."

Dr. Callaghan's Vision for the Future

While Dr. Callaghan's lab has yet to venture into the realm of virtual reality, she sees its potential. "We'd love to do work using virtual reality in the future," she shares. The possibilities are endless: imagine a world where researchers can simulate and study brain responses in various controlled virtual environments, offering even more profound insights into human behavior and cognition.

As she looks ahead, Dr. Callaghan is excited about the potential of interoception – the brain's ability to predict bodily sensations. She believes that by understanding and enhancing this capability, especially during critical periods like pregnancy, we can make significant strides in mental health research.

Dr. Callaghan's journey is a testament to the power of perseverance, collaboration and the marriage of technology and science. As she continues to push the boundaries of neuroscience, one thing is clear: the future is bright, and the possibilities are endless.


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