The role of DNMT3a in fear memories

This 2018 Chinese rodent study found:

“Elevated Dnmt3a [a DNA methyltransferase] level in the dorsal dentate gyrus (dDG) of hippocampus was associated with the absence of fear renewal in an altered context after extinction training. Overexpression and knockdown of Dnmt3a in the dDG regulated the occurrence of fear renewal in a bi-directional manner.

We found that renewal of remote fear memory can be prevented, and the absence of renewal was concurrent with an elevated Dnmt3a level.

Our results indicate that Dnmt3a in the dDG is a key regulator of fear renewal after extinction, and Dnmt3a may play a critical role in controlling fear memory return and thus has therapeutic values.”


The study was a collection of five experiments investigating causes and effects of biology and behavior. The researchers used different techniques to achieve their goals. I’ve quoted extensively below to show some background and results.

“Alterations in histone acetylation and DNA methylation are involved in the formation and extinction of long-term memory..DNMTs catalyze the cytosine methylation and are required to establish and maintain genomic methylation. Dnmt3a and Dnmt3b are de novo DNA methyltransferases. Dnmt1 is the maintenance DNA methyltransferase.

  1. Dnmt3a expression was elevated in the dDG after extinction training followed by a brief memory retrieval (Rec+Ext), which was associated with the absence of fear renewal when tested in an altered context.
  2. Increasing Dnmt3a expression in the dDG using AAV [recombinant adeno-associated virus] expression led to the prevention of fear renewal following a standard extinction training protocol. 
  3. Knockdown of Dnmt3a in the dDG using CRISPR/Cas9 resulted in fear renewal following Rec+Ext protocol.
  4. Renewal of remote fear memory can be prevented using the Rec+Ext protocol.
  5. The absence of renewal was concurrent with an elevated Dnmt3a level.

Current exposure therapy, although effective in many patients, suffers from the inability to generalize its efficacy over time, or is limited by the potential return of adverse memory in the new/novel contexts. These limitations are caused by the context-dependent nature of extinction which is widely viewed as the biological basis of exposure therapy.

Thus, achieving a context-independent extinction may significantly reduce fear renewal to improve the efficacy of exposure therapy. Our current study suggests that the effectiveness of these approaches, and ultimately the occurrence of fear renewal, is determined by the level of Dnmt3a after extinction training, especially in the dDG.

There are two potential mechanisms underlying extinction, one is erasure or updating of the formed memory, and the other is the formation of a new extinction memory which suppresses or competes with the existing memory in a context-dependent manner. While most studies favor the suppression mechanism in the adult, limited studies do suggest that erasure occurs in the immature animals.

We propose that if Dnmt3a level is elevated with extinction training (such as with Rec+Ext protocol), modification to the existing memory occurs and as a consequence extinction does not act as a separate mechanism or form a new memory; but if Dnmt3a level is unaltered with extinction training, a separate extinction memory is formed which acts to suppress or compete with the existing memory.”


The relevant difference between humans and lab rats is that we can ourselves individually change our responses to experiential causes of ongoing adverse effects. Standard methodologies can only apply external treatments such as exposure therapy and manipulating Dnmt3a levels.

https://www.nature.com/articles/s41598-018-23533-w “Dnmt3a in the dorsal dentate gyrus is a key regulator of fear renewal”

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Your need to feel important will run your life, and you’ll never feel satisfied

Yesterday’s team meeting at work provided one display after another of a person’s need to feel important. These eye-openers were the reason the scheduled 30-minute meeting lasted 45 minutes.

Although half of the forty or so attendees are under the age of 40, curiously, only two of them spoke during the meeting. I wasn’t among the older people who had something to say.

Not that I wasn’t tempted by the team-building exercise with its Skittles prompts:

  • Red – Tell us something you do well
  • Orange – Tell us something about your childhood
  • Purple – What could you live without?
  • Yellow – What couldn’t you live without?

Participation in the exercise was voluntary. Yes, I drew an orange Skittle.

Everyone knew there wasn’t enough time for each of us to speak and have the exercise become team-building, yet a dozen people piped up. Every one of the self-selected responses could have been prefaced with “I’m important because..”



There are many needs a person develops and tries to satisfy as substitutes for real needs that weren’t fulfilled. In this blog I’ve focused on the need to feel important.

I started with How do we assess “importance” in our lives? An example from scientists’ research choices and highlighted it on my Welcome page:

“Do you agree that an individual’s need to feel important is NOT a basic human need on the same level as nourishment, protection, and socialization? How does this need arise in our lives?”

I supported an explanation of the need to feel important with evidence and arguments on my Scientific evidence page and said:

“If the explanation is true yet someone rejected it, they at least wouldn’t have suffered from exposure to it. They’ll just remain in our world’s default mode of existence:

  1. Unaware of their own unconscious act-outs to feel important;
  2. Unaware of what’s driving such personal behavior; and
  3. Uninformed of other people’s behavioral origins as a consequence of 1 and 2.”

Other examples of substitute needs include:

What do you think? Any arguments for or against interrupting people’s default mode of existence?

The pain societies instill into children

The human subjects of this 2017 Swiss study had previously been intentionally traumatized by Swiss society:

“Swiss former indentured child laborers (Verdingkinder) were removed as children from their families by the authorities due to different reasons (poverty, being born out of wedlock) and were placed to live and work on farms. This was a practice applied until the 1950s and many of the Verdingkinder were subjected to childhood trauma and neglect during the indentured labor.

DNA methylation modifications indicated experiment-wide significant associations with the following complex posttraumatic symptom domains: dissociation, tension reduction behavior and dysfunctional sexual behavior.”


Imagine being taken away from your family during early childhood for no other reason than your parents weren’t married.

Imagine just a few of the painful feelings such a child had to deal with then and ever since:

  • I’m unloved.
  • Alone.
  • No one can help me.

Imagine some of the ways a child had to adapt during their formative years because of this undeserved punishment:

  • How fulfilling it would be to believe that they were loved, even by someone they couldn’t see, touch, or hear.
  • How fulfilling it would be to get attention from someone, anyone.
  • How a child became conditioned to do things by themself without asking for help.

The study described a minute set of measurements of the subjects’ traumatic experiences and their consequential symptoms. The researchers tried to group this tiny sample of the subjects’ symptoms into a new invented category.

https://bmcresnotes.biomedcentral.com/articles/10.1186/s13104-017-3082-y “A pilot investigation on DNA methylation modifications associated with complex posttraumatic symptoms in elderly traumatized in childhood”


Another example was provided in Is IQ an adequate measure of the quality of a young man’s life?:

“During this time period [between 1955 and 1990], because private adoptions were prohibited by Swedish law, children were taken into institutional care by the municipalities shortly after birth and adopted at a median age of 6 mo, with very few children adopted after 12 mo of age.”

Swedish society deemed local institutional care the initial destination for disenfranchised infants, regardless of whether suitable families were willing and able to adopt the infants. What happened to infants who weren’t adopted by age 1?

Did Swedish society really need any further research to know that an adoptive family’s care would be better for a child than living in an institution?


A third example of the pain instilled into children by societies was related to me last year by two sisters. During the Chinese Cultural Revolution, 1966-1976, among other things, parents were required to be out of their households from dawn to late night, leaving the children to fend for themselves.

One of the daily chores for the sisters at ages 6 and 7, after attending school, was to buy food for dinner and the next day’s breakfast and lunch with ration coupons, and prepare the family’s evening meal. They never met their four grandparents, who had died in ways the sisters either didn’t know or weren’t willing to express to me.

It wasn’t difficult to infer that traumatic childhood events still impacted the women’s lives 50 years later. My empathetic understanding of their histories, though, didn’t improve their current situations.


It’s a challenge for each of us to recognize when our own thoughts, feelings, and behavior provide evidence of childhood pain that’s still with us.

Let’s not develop hopes and beliefs that the societies we live in will resolve these or other adverse effects of childhood trauma its members caused. Other people may guide us, but each of us has to individually get our life back.

Europe, Asia, Africa, Australia, North and South America: every society has its horror stories, and there are people still living who can document last century’s events and circumstances. Have traumatic effects on children from societal policies ceased?

Searching for personal truths – a review of Blade Runner 2049

I saw Blade Runner 2049 yesterday with my 22-year old son. We chose seats with no one in front of us, and got the full impact of sight and sound.

The primary story was one person’s search for his truths: of his origins; of his memories; of his feelings. Who was the infant in the woman’s arms? Are my earliest memories real? Are my feelings true?

The lead character might as well have been lifeless. His activities were dictated by his designated role in society, by what was expected of him. It was no surprise that he preferred ethereal company over people.

He constantly repressed the memories and feelings that were most important to him, that could have given his life meaning. Despite being repressed, his memories and feelings impelled him to discover and confront his truths.

It was a defining moment when his earliest memory was recognized as real:

  • He could feel at last.
  • He could cry at last.
  • He could scream through the cracks in the repression that had produced an unreal, unfeeling existence.

The miracle of life was celebrated, especially at the end. Like the first Blade Runner, society’s members who were deemed unworthy of life were the ones who cherished this fleeting moment most dearly.

See it up close and personal, in a theater with a good screen and sound system.


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Epigenetic effects of early life stress exposure

This 2017 Netherlands review subject was the lasting epigenetic effects of early-life stress:

“Exposure to stress during critical periods in development can have severe long-term consequences..One of the key stress response systems mediating these long-term effects of stress is the hypothalamic-pituitary-adrenal (HPA) axis..early life stress (ELS) exposure has been reported to have numerous consequences on HPA-axis function in adulthood.

ELS is able to “imprint” or “program” an organism’s neuroendocrine, neural and behavioral responses to stress..research focuses along two complementary lines.

Firstly, ELS during critical stages in brain maturation may disrupt specific developmental processes (by altered neurotransmitter exposure, gene transcription, or neuronal differentiation), leading to aberrant neural circuit function throughout life..

Secondly, ELS may induce modifications of the epigenome which lastingly affect brain function..These epigenetic modifications are inducible, stable, and yet reversible, constituting an important emerging mechanism by which transient environmental stimuli can induce persistent changes in gene expression and ultimately behavior.”

In early life, the lower brain and limbic system brain structures are more developed and dominant, whereas the cerebrum and other brain structures are less developed (use the above rodent graphic as a rough guide). Stress and pain generally have a greater impact on the fetus than the infant, and on the infant than the adult.


The reviewers cited 50+ studies from years 2000-2015 in the “Early Life Stress Effects in a “Matching” Stressful Adult Environment” section to argue for the match/mismatch theory:

“Encountering ELS prepares an organism for similar (“matching”) adversities during adulthood, while a mismatching environment results in an increased susceptibility to psychopathology, indicating that ELS can exert either beneficial or disadvantageous effects depending on the environmental context.

Initial evidence for HPA-axis hypo-reactivity is observed for early social deprivation, potentially reflecting the abnormal HPA-axis function as observed in post-traumatic stress disorder.

Interestingly, experiencing additional (chronic) stress in adulthood seems to normalize these alterations in HPA-axis function, supporting the match/mismatch theory.”

Evidence for this theory was contrasted with the allostatic load theory presented in, for example, How one person’s paradigms regarding stress and epigenetics impedes relevant research.


The review mainly cited evidence from rodent studies that mismatched reactions in adulthood may be consequences of early-life events. These events:

“..imprint or program an organism’s neuroendocrine, neural and behavioral responses..leading to aberrant neural circuit function throughout life..which lastingly affect brain function..”

Taking this research to a personal level:

  • Have you had feelings that you were unsafe, although your environment was objectively safe?
  • Have you felt uneasy when people are nice to you?
  • Have you felt anxious when someone pays attention to you, even after you’ve acted to gain their attention?

I assert that mismatched human feelings are one form of mismatched reactions. As such, they may be interpreted as consequences of early-life experiences, and indicators of personal truths.

If researchers can let go of their biases and Advance science by including emotion in research, they may find that human subjects’ feelings produce better evidence for what actually happened during the subjects’ early lives than do standard scientific methods of:

Incorporating this evidence may bring researchers closer to backwardly predicting the major insults to an individual that knocked their development processes out of normally robust pathways and/or induced “persistent changes in gene expression and ultimately behavior.”

https://www.frontiersin.org/articles/10.3389/fncel.2017.00087/full “Modulation of the Hypothalamic-Pituitary-Adrenal Axis by Early Life Stress Exposure”


I discovered this review as a result of it being cited in http://www.sciencedirect.com/science/article/pii/S1084952117302884 “Long-term effects of early environment on the brain: Lesson from rodent models” (not freely available)

Prisoners of our childhoods

Same old shit – another failed relationship.

Coincident with the start of our relationship, I was struck by a phrase by Dr. Janov, posted in Beyond Belief: What we do instead of getting well:

“It doesn’t matter about the facts we know..if we cannot maintain a relationship with someone else.”

I kept that thought in the forefront.

Both of us are prisoners of our childhoods. I’ve tried to see and feel the walls and bars for what they are.

J hadn’t tried to process the reality of her childhood and life. For example, on her birthday I asked her how she celebrated her birthdays when she was growing up. She provided a few details, then mentioned that her parents had skipped some of her birthdays. Although I had no immediate reaction, she quickly said that she had a happy childhood.

I was at fault, too, of course. I again asked a woman to marry me who hadn’t ever told me she loved me, except in jest.

I asked J to marry me around the six-month point of our relationship. I felt wonderful, in love with her that August morning after she slept with me at my house. I made an impromptu plan: in the middle of a four-mile walk, I asked her to marry me while kneeling before her as she sat on a bench outside a jewelry store. But she wouldn’t go in to choose a ring. She said she’d think about it.

A month later, after several dates, sleepovers at her house, and a four-day trip to Montreal, I again brought up marriage while we rested on her large couch in her nice sun room. The thing I felt would be wonderful brought about the end.

I tried to understand why she couldn’t accept me for the person who I intentionally showed her I am. She abstracted everything that she said.

I tried to get her to identify why, after all the times we cared for each other, after all our shared experiences, she didn’t want me around anymore.

Didn’t happen. She didn’t tell me things that made sense as answers to my questions.

One thing she said without abstraction was that I was weak for showing my feelings. She told me I was clingy.

Another thing she communicated at the end shocked me. She somehow thought that I was going to dump her. I said that the thought never even crossed my mind.

I didn’t recognize it as projection at the time. Prompted by her underlying feelings, she attributed to me the actions and thoughts that only she herself had.


One thing I’ve felt after the end was that the need underlying my only stated relationship goal – to live with a woman I love who also loves me – is again ruining my life. My latest efforts towards that goal were rife with unconscious symbolic act outs of an unsatisfied need from my early life.

That unrelenting need is for a woman’s love. The women I’ve chosen, though, have always given me what I got from my mother: they wouldn’t accept me as I am, and didn’t love me.

My prison cell is what Dr. Janov calls the imprint where I – as a child, teenager, young man, middle-aged man, old man – futilely attempt to change the past.

I’ve tried to put myself in J’s place. How horrible must it have been for her to be steadily intimate with a man and not feel that his touches, kisses, words, affection, expressed love? That he couldn’t really love me, and so I couldn’t love him? That he was actually after something else: sex, property, etc., because it was impossible that he loved me?

“Standing next to me in this lonely crowd
Is a man who swears he’s not to blame
All day long I hear him shout so loud
Crying out that he was framed
I see my light come shining
From the west unto the east
Any day now, any day now
I shall be released”


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On Primal Therapy with Drs. Art and France Janov

Experiential feeling therapy addressing the pain of the lack of love.