Amygdala

Both sexes can be skilled child caregivers when we put time and effort into it

gettingwell4 2-3 stars Required further work, Amygdala, Brain development, Cerebrum, Limbic system

My POV of this 2014 Israeli study’s findings, at the risk of being dragged into the politically-correct quagmire:

  • Mothers (heterosexual primary-caregiving) mainly used areas of their limbic systems to care for children;
  • Fathers (heterosexual secondary-caregiving) mainly used areas of their cerebrums to care for children;
  • Fathers (homosexual primary-caregiving) mainly used both their limbic systems and cerebrums to care for children.

Findings of the “duh” variety:

  • Women have a built-in capacity to care for children before they have children;
  • Men can learn to care for children;
  • Both sexes can be skilled child caregivers when we put time and effort into it.

“Although only mothers experience pregnancy, birth, and lactation, and these provide powerful primers for the expression of maternal care via amygdala sensitization, evolution created other pathways for adaptation to the parental role in human fathers, and these alternative pathways come with practice, attunement, and day-by-day caregiving.”

http://www.pnas.org/content/111/27/9792.full “Father’s brain is sensitive to childcare experiences”

Stress impairs the normal matching of neuronal activity to increased blood flow in the amygdala

gettingwell4 4-5 stars Advanced knowledge, Amygdala, Cortisol, Limbic system, Neurochemicals, Stress

This 2014 rodent study showed one aspect of how stress changed the amygdala. Stress didn’t allow normal matching of neuronal activity to increased blood flow:

“Chronic stress — which is a contributing factor for many diseases — impairs neurovascular coupling in the amygdala..

Neurovascular coupling (is) the process that matches neuronal activity with increased local blood flow.”

http://www.pnas.org/content/111/20/7462.full “Stress-induced glucocorticoid signaling remodels neurovascular coupling through impairment of cerebrovascular inwardly rectifying K+ channel function”

The effects of early-life stress are permanent alterations in the child’s brain circuitry and function

gettingwell4 4-5 stars Advanced knowledge, Amygdala, Brain development, Cortisol, Limbic system, Memory, Neurochemicals, Stress ,

The sobering application of this 2013 rodent study’s finding was that if the limbic systems of human children weren’t already permanently damaged before they entered an orphanage, the orphanage experience would probably do that to them:

“The current study manipulates the type and timing of a stressor and the specific task and age of testing to parallel early-life stress in humans reared in orphanages.

The results provide evidence of both early and persistent alterations in amygdala circuitry and function following early-life stress.

These effects are not reversed when the stressor is removed nor diminished with the development of prefrontal regulation regions.”

http://www.pnas.org/content/110/45/18274.full “Early-life stress has persistent effects on amygdala function and development in mice and humans”

One way that mothers cause fear and emotional trauma in their infants

gettingwell4 4-5 stars Advanced knowledge, Amygdala, Brain development, Cortisol, Epigenetics, Limbic system, Memory, Neurochemicals, Stress , , ,

This 2014 rodent study showed that infants learned to fear specific items in the environment that their mothers feared. The imprinting memory happened at a stage in the infants’ lives when they hadn’t yet developed the physiology to respond to the environment with fear on their own.

The learning cue was the mothers’ fear response – in this case, her distress odor, even when the mother was not present – coupled with the infants’ stress. The fear memory was stored in the infants’ amygdalae:

“These memories are acquired at younger ages compared with amygdala-dependent odor-shock conditioning and are more enduring following minimal conditioning.

Our results provide clues to understanding transmission of specific fears across generations and its dependence upon maternal induction of pups’ stress response paired with the cue to induce amygdala-dependent learning plasticity.”

There’s no scientific reason why this and related studies shouldn’t inform researchers who ignore the earliest stages of human life when studying limbic system disorders in humans.

For an example of researchers choosing to NOT be informed, look at Is this science, or a PC agenda? Problematic research on childhood maltreatment and its effects.

http://www.pnas.org/content/111/33/12222.full “Intergenerational transmission of emotional trauma through amygdala-dependent mother-to-infant transfer of specific fear”

Is this science, or a PC agenda? Problematic research on childhood maltreatment and its effects

gettingwell4 < 0 Detracted from science, Amygdala, Brain development, Epigenetics, Hippocampus, Limbic system, Lower brain, Memory, Stress ,

This 2013 Wisconsin human study’s goal was to assess effects of childhood trauma using both functional MRI scans and self-reported answers to a questionnaire. The families of the study’s subjects (64 18-year-olds) participated with researchers before some of the teenagers were born.

How could the teenagers give answers that described events that may have taken place early in their lives, before their cerebrums were developed, around age 4? Even if the subjects were old enough to remember, would they give accurate answers to statements such as:

“My parents were too drunk or high to take care of the family.

Somebody in my family hit me so hard that it left me with bruises or marks.”

knowing that affirmative answers would prompt a visit to their family from a government employee?

Although some data may have been available, data from the teenagers’ prenatal, birth term, infancy, and early childhood wasn’t part of the study design. Intentional dismissal of early influencing factors ignored applicable research!

No

Was the study’s limited window due to the political incorrectness of placing importance in the development environment provided by the subjects’ mothers? The evidence was there for those willing to see.

One clue of ignored early traumatic events was provided by the lead researcher’s quote in news coverage:

“These kids seem to be afraid everywhere,” he says. “It’s like they’ve lost the ability to put a contextual limit on when they’re going to be afraid and when they’re not.”

This finding of “fear without context” possibly described the later-life effects of traumas that were encountered in utero and during infancy. A pregnant woman’s terror and fear can register on the fetus’ lower brain and the amygdala from the third trimester onward.

Storing a memory’s context is one of the functions that the hippocampus performs. Because the hippocampus develops later than the amygdala, though, it would be unable to provide a context for any earlier feelings and sensations such as fear and terror.

The researchers attempted to place the finding of unfocused fear into later stages of child development without doing the necessary research. They tried to force this finding into the subjects’ later development years by citing rat fear-extinction and other marginally related studies.

But citing these studies didn’t make them applicable to the current study. Cause and effect wasn’t demonstrated by noting various “is associated with” findings.

Was this science? Was it part of furthering an agenda like protecting publicly funded jobs?

Was this study published to make a contribution to science? Were the peer reviewers even interested in advancing science?

And what about the 64 18-year-old subjects? If the lead researcher’s statement was accurate, did these teenagers receive help that addressed what they really needed?

http://www.pnas.org/content/110/47/19119.full “Childhood maltreatment is associated with altered fear circuitry and increased internalizing symptoms by late adolescence”

This page has somehow become a target for spammers, and I’ve disabled comments. Readers can comment on other pages or posts and indicate that they want their comment to apply here, and I’ll re-enable comments.

Hippocampal mechanisms involved in the enhancement of fear extinction caused by exposure to novelty

gettingwell4 2-3 stars Required further work, Amygdala, Hippocampus, Limbic system, Memory

This 2014 Brazilian rodent study provided more information on the workings of the hippocampus. The researchers measured the effects of re-experiencing a fear within a specific context:

“Within a restricted time window, a brief exposure to a novel environment enhances the extinction of contextual fear.

The enhancement of extinction by the exposure to novelty depends on hippocampal gene expression..on hippocampal but not amygdalar processes.”

http://www.pnas.org/content/111/12/4572.full “Hippocampal molecular mechanisms involved in the enhancement of fear extinction caused by exposure to novelty”

How painful long-lasting memories are stored and why they are so strong

gettingwell4 2-3 stars Required further work, Amygdala, Cortisol, Limbic system, Memory, Neurochemicals, Stress , ,

This 2014 rodent study provided evidence for a portion of the neurophysiology that underlies how painful long-lasting memories are stored and why they are so strong. The amygdala was the brain area studied.

The researchers were misguided in news coverage by focusing on solutions such as external mechanisms to forget these memories. The researchers should think in terms of how their research can help people who can help themselves instead of having something externally done to them.

After all, we’re humans who can participate in therapy, not lab rats who need to be fixed.

http://www.pnas.org/content/111/51/E5584.full “Hebbian and neuromodulatory mechanisms interact to trigger associative memory formation”

Are 50 Shades of Grey behaviors learned in infancy?

gettingwell4 5+ stars Premium, Amygdala, Brain development, Cerebrum, Cortisol, Epigenetics, Hypothalamus, Limbic system, Lower brain, Memory, Neurochemicals, Primal Therapy, Serotonin, Stress , , , , , ,

Ever wonder how someone could become attached to their early childhood abuser?

Ever wonder what underlying neurobiological conditions may account for the popularity of Fifty Shades of Grey?

This 2014 rodent study “Enduring good memories of infant trauma” linked below showed how trauma changed infants’ limbic system and lower brains. As adults, they derived a neurochemical benefit from re-experiencing the traumatic conditions:

“Trauma and pain experienced in infancy clearly led to higher rates of adult rat depression-like behavior..(but) the infant brain has limited ability to link trauma to fear areas in the brain, such as the amygdala.

These results are surprising because cues associated with trauma experienced as adults provoke fear and do not rescue depressive behavior.

It is possible that giving SSRI medications to children could be detrimental to mental health in adulthood,” Dr. Sullivan says. “We believe that our research offers the first evidence for the impact of serotonin pathways.

The infant trauma increases serotonin to produce brain programming of later life depression, and the infant trauma cue increases serotonin to alleviate the adult depressive like symptoms.”

As the study may apply to humans, let’s say that as an infant, someone was traumatized by a caregiver who, for example, bound them too tightly and left them alone for too long. What adult behaviors and other symptoms may develop as results? The person may:

  • Show depression-like symptoms that would strangely be alleviated by being bound tightly and left alone for an extended period.
  • Develop attachments to people who treated them poorly in a way that triggered them to re-experience their early childhood traumas.
  • Feel their mood lift when their infancy traumas were cued.
  • Be unable to explain and integrate with their cerebrum what was going on with their limbic system and lower brains.
  • Be caught in a circle of acting out their feelings and impulses, with unfulfilling results.

Isn’t it curious that this acting-out behavior – driven by unconscious memories of traumatic conditions – is a subject for popular entertainment? It may have resonated with personal experiences of the people who read the books and watched the movie.

What about people who want to be relieved of their symptomatic behavior? Is it a justifiable practice:

  • To pass affected people over to talk therapies that aren’t interested in directly treating the cause – a neurobiological condition that exists in the limbic system and lower brains – only the symptoms?
  • To drug affected people with the neurochemicals that their condition makes scarce – the symptoms – instead of addressing the source?

A principle of Dr. Arthur Janov’s Primal Therapy is that people are capable of treating their own originating neurobiological conditions. One of the therapeutic results is that the patient is relieved of being caught in endless circles of acting-out behavior.

That way we can have our own lives, and not be driven by what happened during early stages of our lives.

http://www.pnas.org/content/112/3/881.full “Enduring good memories of infant trauma: Rescue of adult neurobehavioral deficits via amygdala serotonin and corticosterone interaction”

Making lasting memories: Remembering the significant

gettingwell4 4-5 stars Advanced knowledge, Amygdala, Cerebrum, Hippocampus, Limbic system, Memory, Stress

This 2013 article summarized 158 studies related to the roles of regions in the limbic system and memory:

“Episodic memory is the capacity to recall specific experiences and to re-experience individual events.

The findings of both animal and human studies provide compelling evidence that stress-induced activation of the amygdala and its interactions with other brain regions involved in processing memory play a critical role in ensuring that emotionally significant experiences are well-remembered.”

http://www.pnas.org/content/110/Supplement_2/10402.full “Making lasting memories: Remembering the significant”

Conscious mental states should not be the first-choice explanation of behavior

gettingwell4 4-5 stars Advanced knowledge, Amygdala, Cerebrum, Hippocampus, Limbic system, Memory , ,

Here are some 2014 ruminations by Joseph LeDoux, the grandfather of studies of the amygdala. He attempted to disambiguate feeling brain structures’ activations and responses from ideas of what feelings are, specifically regarding fear:

“Damage to the hippocampus in humans disrupts explicit conscious memory of having been conditioned but has no effect on fear conditioning itself, whereas damage to the amygdala disrupts fear conditioning but not the conscious memory of having been conditioned.

Conscious mental states should not, in the absence of direct evidence, be the first-choice explanation of behavior.

Neither amygdala activity nor amygdala-controlled responses are telltale signatures of fearful feelings.

Conscious fear can cause us to act in certain ways, but it is not the cause of the expression of defensive behaviors and physiological responses elicited by conditioned or unconditioned threats.”

http://www.pnas.org/content/111/8/2871.full “Coming to terms with fear”