Life Stressors Trigger Neurological Disorders

Fresh from the "Does a bear shit in the woods?" file, this new study confirms that early life stressors trigger neurological and psychological disorders.

According to Heller and LaPierre (see "Working with the Capacity for Connection in Healing Developmental Trauma"*), there is an extensive list of pre- and post-natal events that can lead to mental illness in adulthood (largely due to the inadequate formation of right brain affect regulation skills and interpersonal skills:

Early Events That May Cause Long-Term Traumatic Reactions
From Conception to 6 Months after Birth (partial list)

Attachment and Developmental Trauma • Being carried in the womb of a mother who does not want you
• Being carried in the womb of a traumatized, dissociated, depressed or anxious mother
• Serious consideration of abortion
• Mother abusing alcohol or drugs during pregnancy
• Feeling rejected, blamed, or even hated by one or both parents
• One or both parents struggling with Connection issues themselves
• Attachment attempts with a dissociated, chronically depressed, anxious, or angry mother
• A psychotic or borderline mother
• Being made to feel like a burden
• Physical or emotional abuse
• Neglect
• Adoption
Shock Trauma
• Attempted abortion
• Mother's death in childbirth
• Premature birth
• Long, painful delivery
• Extended incubation with insufficient physical contact
• Early surgeries
• Significant traumatic events for the mother or other members of the family
• Death in the family
• Traumatic loss and bereavement
• Being born into wartime, depression, significant poverty
• Intergenerational trauma such as being born to Holocaust survivors
• Natural disasters

Clearly, this "new" research is simply confirmation of what we have known on the therapeutic side of things for a couple of decades now. The main difference, as I see it, is that the neuroscience side is identifying the genetic triggers that are pulled when we are exposed to life stressors. The same thing is very likely true in physical illness.

As an example of the later, my mother had been in remission from ovarian cancer for 3 years when my sister died. Within 2-3 months, my mother's cancer had returned and metastasized throughout her body. I doubt this would have happened so quickly without the stress of my sister's death. 

* This article is excerpted from Healing Developmental Trauma: How Early Trauma Affects Self-Regulation, Self-Image, and the Capacity for Relationship (2012)

Life stressors trigger neurological disorders, researchers find

Date: April 22, 2014
Source: Children's National Medical Center

Summary:
When mothers are exposed to trauma, illness, alcohol or other drug abuse, these stressors may activate a single molecular trigger in brain cells that can go awry and activate conditions such as schizophrenia, post-traumatic stress disorder and some forms of autism. Until now, it has been unclear how much these stressors have impacted the cells of a developing brain. Past studies have shown that when an expectant mother exposes herself to alcohol or drug abuse or she experiences some trauma or illness, her baby may later develop a psychiatric disorder later in life. But the new findings identify a molecular mechanism in the prenatal brain that may help explain how cells go awry when exposed to certain environmental conditions.


While it has been generally accepted that exposure to harmful environmental factors during pregnancy increase the susceptibility of the brain to neurological and psychiatric disorders, new types of environmental agents are continuingly added to the mix, requiring evolving studies, Hasimoto-Torii says. Credit: © pekkic / Fotolia
When mothers are exposed to trauma, illness, alcohol or other drug abuse, these stressors may activate a single molecular trigger in brain cells that can go awry and activate conditions such as schizophrenia, post-traumatic stress disorder and some forms of autism.

Until now, it has been unclear how much these stressors have impacted the cells of a developing brain. Past studies have shown that when an expectant mother exposes herself to alcohol or drug abuse or she experiences some trauma or illness, her baby may later develop a psychiatric disorder, including some forms of autism or post-traumatic stress disorder, later in life. But the new findings, published online in Neuron, identifies a molecular mechanism in the prenatal brain that may help explain how cells go awry when exposed to certain environmental conditions.

Kazue Hasimoto-Torii, PhD, Principal Investigator of the Center for Neuroscience, Children's National Health System, and a Scott-Gentle Foundation investigator, is lead author of the paper. Torii was previously at Yale, whose researchers were co-authors in the report. The research was funded primarily through National Institutes of Health grants.

Researchers found that mouse embryos exposed to alcohol, methyl-mercury, or maternal seizures activate a single gene, HSF1, also known as heat shock factor, in cerebral cortex. The HSF1 "plays a crucial role in the response of brain cells to prenatal environmental insults," the researchers reported. "The gene protects and enables brain cells to survive prenatal assaults. Mice lacking the HSF1 gene showed structural brain abnormalities and were prone to seizures after birth following exposures to very low levels of toxins."

Even in mice where the HSF1 gene was properly activated to combat environmental insults, the molecular mechanism alone may permanently change how brain cells respond, and may be a reason why someone may be more susceptible to neuropsychiatric disorders later in life.

Innovative work with stem cells also provided findings that supported the theory that stress induces vulnerable cells to malfunction, the researchers reported. For the study, researchers created stem cells from biopsies of people diagnosed with schizophrenia. Stem cells are capable of becoming many different tissue types, including neurons. In the study, genes from the stem cells of those with schizophrenia responded more dramatically when exposed to environmental insults than stem cells from non-schizophrenic individuals.

While it has been generally accepted that exposure to harmful environmental factors increase the susceptibility of the brain to neurological and psychiatric disorders, new types of environmental agents are continuingly added to the mix, requiring evolving studies, Hasimoto-Torii says.

Hashimoto-Torii notes that autism rates have increased substantially and "more people are having these exposures to environmental stressors," she says. While there have been many studies that have identified singular stressors, such as alcohol, there have not been enough studies to focus on many different environmental factors and their impacts, such as heavy metals as well as alcohol and other toxic exposure, she adds.

Identifying many risk factors helped Hashimoto-Torii and other researchers identify the gene that may be linked to neurological problems. "Different stressors may have different stress responses," she says. She examined risk factors specifically involving epilepsy, ADHD, autism and schizophrenia. Eventually, it may open the door "to provide therapy in the future to reduce the risk" and protect vulnerable cells.


Story Source:
The above story is based on materials provided by Children's National Medical Center. Note: Materials may be edited for content and length.

Journal Reference:
Kazue Hashimoto-Torii, Masaaki Torii, Mitsuaki Fujimoto, Akira Nakai, Rachid El Fatimy, Valerie Mezger, Min J. Ju, Seiji Ishii, Shih-hui Chao, Kristen J. Brennand, Fred H. Gage, Pasko Rakic. (2014). Roles of Heat Shock Factor 1 in Neuronal Response to Fetal Environmental Risks and Its Relevance to Brain Disorders. Neuron; DOI: 10.1016/j.neuron.2014.03.002

Recent Research in Brain Science - Stress, Stem Cells, Switchboards, and More

It seems there is a new and important brain science research study published almost every day - and sometimes multiple studies in the same day. I do my best to blog the biggest ones, but sometimes there is not time to get them all up, so then I do a post like this one - a kind of link dump of new and important studies.

First up (in no particular order), a study that provides some clues at to how neurological disorders develop in the brain, by looking at neural circuitry.

Circuits In The Brain Reveal Why Neurological Disorders Occur

The human brain contains billions of neurons that are arranged in complex circuits, which enable people to function with regard to controlling movements, perceiving the world and making decisions. In order to understand how the brain works and what malfunctions occur in neurological disorders it is crucial to decipher these brain circuits.

Read the whole article.

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This piece looks at a study from Scripps Research Institute that may have identified the stem cell population that develops into the brain cells of the cerebral cortex.

Study Of Brain Development Reveals Brain Stem Cells That May Be Responsible For Higher Functions, Bigger Brains

Published in the journal Science, the new research reveals how neurons in the uppermost layers of the cerebral cortex form during embryonic brain development.

"The cerebral cortex is the seat of higher brain function, where information gets integrated and where we form memories and consciousness," said the study's senior author Ulrich Mueller, a professor and director of the Dorris Neuroscience Center at Scripps Research. "If we want to understand who we are, we need to understand this area where everything comes together and forms our impression of the world." 

Read the whole article.

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We have long known that someplace in the brain there are circuits or a module that sorts through all of the incoming stimuli (sound, vision, scent, taste, touch, temperature, and so on) and decides what needs to make it into awareness and what does not. Now we think we have found that "switchboard."

After producing neural connection maps, the researchers used electrodes (blue arrows and green crosshairs) to monitor the direct communication paths (yellow-orange) between the pulvinar and clusters of brain cells, which in this case are in the temporal lobe. (Credit: Courtesy of /AAAS)

Brain's Mysterious Switchboard Operator Revealed

ScienceDaily (Aug. 17, 2012) — A mysterious region deep in the human brain could be where we sort through the onslaught of stimuli from the outside world and focus on the information most important to our behavior and survival, Princeton University researchers have found.

The researchers report in the journal Science that an area of our brain called the pulvinar regulates communication between clusters of brain cells as our brain focuses on the people and objects that need our attention. Like a switchboard operator, the pulvinar makes sure that separate areas of the visual cortex -- which processes visual information -- are communicating about the same external information, explained lead author Yuri Saalmann, an associate research scholar in the Princeton Neuroscience Institute (PNI). Without guidance from the pulvinar, an important observation such as an oncoming bus as one is crossing the street could get lost in a jumble of other stimuli.

Read the whole article.

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Lastly, we have two studies that reveal the impact of stress on cells (including brain cells) and on the brain directly. Let's just say, It ain't good.

Control Of Gene Activity Altered By Acute Stress

Acute stress alters the methylation of the DNA and thus the activity of certain genes. This is reported by researchers at the Ruhr-Universitat Bochum together with colleagues from Basel, Trier and London for the first time in the journal Translational Psychiatry. "The results provide evidence how stress could be related to a higher risk of mental or physical illness", says Prof. Dr. Gunther Meinlschmidt from the Clinic of Psychosomatic Medicine and Psychotherapy at the LWL University Hospital of the RUB. The team looked at gene segments which are relevant to biological stress regulation.

Epigenetics - the "second code" - regulates gene activity

Our genetic material, the DNA, provides the construction manual for the proteins that our bodies need. Which proteins a cell produces depends on the cell type and the environment. So-termed epigenetic information determines which genes are read, acting quasi as a biological switch. An example of such a switch is provided by methyl (CH3) groups that attach to specific sections of the DNA and can remain there for a long time - even when the cell divides. Previous studies have shown that stressful experiences and psychological trauma in early life are associated with long-term altered DNA methylation. Whether the DNA methylation also changes after acute psychosocial stress, was, however, previously unknown.

Read the whole article.

The second article showed that chronic stress, like chronic depression, can shrink the brain - literally.

Stress, Depression Reduce Brain Volume Thanks to Genetic ‘Switch’

By Rick Nauert PhD Senior News Editor
Reviewed by John M. Grohol, Psy.D. on August 13, 2012 

 

 

Scientists have known that stress and depression can cause the brain to retract or lose volume, a condition associated with both emotional and cognitive impairment. Now, a new study discovers why this occurs.

Yale scientists have found that the deactivation of a single genetic switch can instigate a cascading loss of brain connections in humans and depression in animal models.

Researchers say the genetic switch, known as a transcription factor, represses the expression of several genes that are necessary for the formation of synaptic connections between brain cells. The loss of connections, in turn, can contribute to loss of brain mass in the prefrontal cortex, say the scientists.

Read the whole article.