Hilgra

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See, that’s what the app is perfect for.

Sounds perfect Wahhhh, I don’t wanna
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Ten core principles necessary for the remodeling of your brain to take place:

1. Change is mostly limited to those situations in which the brain is in the mood for it.

If you are alert, on the ball, engaged, motivated, ready for action, the brain releases the neurochemicals necessary to enable brain change. When disengaged, inattentive, distracted, or doing something without thinking that requires no real effort, your neuroplastic switches are “off.”

2. The harder you try, the more you’re motivated, the more alert you are, and the better (or worse) the potential outcome, the bigger the brain change.

If you’re intensely focused on the task and really trying to master something for an important reason, the change experienced will be greater.

3. What actually changes in the brain are the strengths of the connections of neurons that are engaged together, moment by moment, in time.

The more something is practiced, the more connections are changed and made to include all elements of the experience (sensory info, movement, cognitive patterns). You can think of it like a “master controller” being formed for that particular behavior which allows it to be performed with remarkable facility and reliability over time.

4. Learning-driven changes in connections increase cell-to-cell cooperation which is crucial for increasing reliability.

Merzenich explains this by asking you to imagine the sound of a football stadium full of fans all clapping at random versus the same people clapping in unison. He explains, “The more powerfully coordinated your [nerve cell] teams are, the more powerful and more reliable their behavioral productions.”

5. The brain also strengthens its connections between teams of neurons representing separate moments of successive things that reliably occur in serial time.

This allows your brain to predict what happens next and have a continuous “associative flow.” Without this ability, your stream of consciousness would be reduced to “a series of separate, stagnating puddles,” explains Merzenich.

6. Initial changes are temporary.

Your brain first records the change, then determines whether it should make the change permanent or not. It only becomes permanent if your brain judges the experience to be fascinating or novel enough or if the behavioral outcome is important, good or bad.

7. The brain is changed by internal mental rehearsal in the same ways and involving precisely the same processes that control changes achieved through interactions with the external world.

According to Merzenich, “You don’t have to move an inch to drive positive plastic change in your brain. Your internal representations of things recalled from memory work just fine for progressive brain plasticity-based learning.”


8. Memory guides and controls most learning.

As you learn a new skill, your brain takes note of and remembers the good attempts, while discarding the not-so-good trys. Then, it recalls the last good pass, makes incremental adjustments, and progressively improves.

9. Every movement of learning provides a moment of opportunity for the brain to stabilize – and reduce the disruptive power of – potentially interfering backgrounds or “noise.”

Each time your brain strengthens a connection to advance your mastery of a skill, it also weakens other connections of neurons that weren’t used at that precise moment. This negative plastic brain change erases some of the irrelevant or interfering activity in the brain.

10. Brain plasticity is a two-way street; it is just as easy to generate negative changes as it is positive ones.

You have a “use it or lose it” brain. It’s almost as easy to drive changes that impair memory and physical and mental abilities as it is to improve these things. Merzenich says that older people are absolute masters at encouraging plastic brain change in the wrong direction.

Foetal Circulation

biomedicool

Main blood flow:

Placenta → umbilical vein → ductus venosus → inferior vena cava →  right atrium → foramen ovale → left atrium → left ventricle → aorta →           hypogastric arteries → umbilical arteries → placenta.

Blood that passes from the right atrium to the right ventricle travels:
Right ventricle → pulmonary trunk → ductus arteriosus → aorta

image
  •  Oxygenated blood returns from the placenta through the umbilical vein 
  • enters the portal venous system
  • enters the inferior vena cava by way of the ductus venosus.
  •  partly deflected across the foramen ovale into the left atrium.
  • Because of a streaming effect, almost all superior vena caval blood passes directly through the tricuspid valve, entering the right ventricle.
  • Most of the blood bypasses the high-resistance, unexpanded lungs and passes through the ductus arteriosus into the descending aorta.  
  • The major portion of blood ejected from the left ventricle supplies the brain and upper body to the descending aorta, where it joins with the large stream from the ductus arteriosus before flowing to the lower body and back to the placenta.

Foetal cardiovascular physiology

  • alveoli are fluid filled
  • pulmonary arteries and arterioles =thick walls and a small lumen, similar to arteries in the systemic circulation. 
  • low pulmonary blood flow  (7% to 10% of the total cardiac output) = due to high pulmonary vascular resistance. 
  • pulmonary vessels are highly reactive to changes in oxygen tension or in the pH of blood perfusing them .

Shunts

3 shunts exist in utero which allow blood to bypass the lungs, liver and kidneys, whose functions are performed by the placenta

  • foramen ovale  - blood travels from the right atrium to the left atrium
  • ductus venosus - blood from the umbilical vein bypasses the liver to enter the inferior vena cava
  • ductus arteriosus - blood passes from the pulmonary trunk into the aorta
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Circulación fetal