Stress Mastery

What is the “fight or flight response?”

This fundamental physiologic response forms the foundation of modern day stress medicine. The “fight or flight response” is our body’s primitive, automatic, inborn response that prepares the body to “fight” or “flee” from perceived attack, harm or threat to our survival.

What happens to us when we are under excessive stress?

When we experience excessive stress—whether from internal worry or external circumstance—a bodily reaction is triggered, called the “fight or flight” response. Originally discovered by the great Harvard physiologist Walter Cannon, this response is hard-wired into our brains and represents a genetic wisdom designed to protect us from bodily harm. This response actually corresponds to an area of our brain called the hypothalamus, which—when stimulated—initiates a sequence of nerve cell firing and chemical release that prepares our body for running or fighting.

What are the signs that our fight or flight response has been stimulated (activated)?

When our fight or flight response is activated, sequences of nerve cell firing occur and chemicals like adrenaline, noradrenaline and cortisol are released into our bloodstream. These patterns of nerve cell firing and chemical release cause our body to undergo a series of very dramatic changes. Our respiratory rate increases. Blood is shunted away from our digestive tract and directed into our muscles and limbs, which require extra energy and fuel for running and fighting. Our pupils dilate. Our awareness intensifies. Our sight sharpens. Our impulses quicken. Our perception of pain diminishes. Our immune system mobilizes with increased activation. We become prepared—physically and psychologically—for fight or flight. We scan and search our environment, “looking for the enemy.”

When our fight or flight system is activated, we tend to perceive everything in our environment as a possible threat to our survival. By its very nature, the fight or flight system bypasses our rational mind—where our more well thought out beliefs exist—and moves us into “attack” mode. This state of alert causes us to perceive almost everything in our world as a possible threat to our survival. As such, we tend to see everyone and everything as a possible enemy. Like airport security during a terrorist threat, we are on the look out for every possible danger. We may overreact to the slightest comment. Our fear is exaggerated. Our thinking is distorted. We see everything through the filter of possible danger. We narrow our focus to those things that can harm us. Fear becomes the lens through which we see the world.

We can begin to see how it is almost impossible to cultivate positive attitudes and beliefs when we are stuck in survival mode. Our heart is not open. Our rational mind is disengaged. Our consciousness is focused on fear, not love. Making clear choices and recognizing the consequences of those choices is unfeasible. We are focused on short-term survival, not the long-term consequences of our beliefs and choices. When we are overwhelmed with excessive stress, our life becomes a series of short-term emergencies. We lose the ability to relax and enjoy the moment. We live from crisis to crisis, with no relief in sight. Burnout is inevitable. This burnout is what usually provides the motivation to change our lives for the better. We are propelled to step back and look at the big picture of our lives—forcing us to examine our beliefs, our values and our goals.

What is our fight or flight system designed to protect us from?

Our fight or flight response is designed to protect us from the proverbial saber tooth tigers that once lurked in the woods and fields around us, threatening our physical survival. At times when our actual physical survival is threatened, there is no greater response to have on our side. When activated, the fight or flight response causes a surge of adrenaline and other stress hormones to pump through our body. This surge is the force responsible for mothers lifting cars off their trapped children and for firemen heroically running into blazing houses to save endangered victims. The surge of adrenaline imbues us with heroism and courage at times when we are called upon to protect and defend the lives and values we cherish.

What are the saber tooth tigers of today and why are they so dangerous?

When we face very real dangers to our physical survival, the fight or flight response is invaluable. Today, however, most of the saber tooth tigers we encounter are not a threat to our physical survival. Today’s saber tooth tigers consist of rush hour traffic, missing a deadline, bouncing a check or having an argument with our boss or spouse. Nonetheless, these modern day, saber tooth tigers trigger the activation of our fight or flight system as if our physical survival was threatened. On a daily basis, toxic stress hormones flow into our bodies for events that pose no real threat to our physical survival.

Once it has been triggered, what is the natural conclusion of our fight or flight response?

By its very design, the fight or flight response leads us to fight or to flee—both creating immense amounts of muscle movement and physical exertion. This physical activity effectively metabolizes the stress hormones released as a result of the activation of our fight or flight response. Once the fighting is over, and the threat—which triggered the response—has been eliminated, our body and mind return to a state of calm.

Has the fight or flight response become counterproductive?

In most cases today, once our fight or flight response is activated, we cannot flee. We cannot fight. We cannot physically run from our perceived threats. When we are faced with modern day, saber tooth tigers, we have to sit in our office and “control ourselves.” We have to sit in traffic and “deal with it.” We have to wait until the bank opens to “handle” the bounced check. In short, many of the major stresses today trigger the full activation of our fight or flight response, causing us to become aggressive, hypervigilant and over-reactive. This aggressiveness, over-reactivity and hypervigilance cause us to act or respond in ways that are actually counter-productive to our survival. Consider road rage in Los Angeles and other major cities.

It is counterproductive to punch out the boss (the fight response) when s/he activates our fight or flight response. (Even though it might bring temporary relief to our tension!) It is counterproductive to run away from the boss (the flight response) when s/he activates our fight or flight response. This all leads to a difficult situation in which our automatic, predictable and unconscious fight or flight response causes behavior that can actually be self-defeating and work against our emotional, psychological and spiritual survival.

Is there a cumulative danger from over-activation of our fight or flight response?

Yes. The evidence is overwhelming that there is a cumulative buildup of stress hormones. If not properly metabolized over time, excessive stress can lead to disorders of our autonomic nervous system (causing headache, irritable bowel syndrome, high blood pressure and the like) and disorders of our hormonal and immune systems (creating susceptibility to infection, chronic fatigue, depression, and autoimmune diseases like rheumatoid arthritis, lupus, and allergies.)

To protect ourselves today, we must consciously pay attention to the signals of fight or flight.

To protect ourselves in a world of psychological—rather than physical—danger, we must consciously pay attention to unique signals telling us whether we are actually in fight or flight. Some of us may experience these signals as physical symptoms like tension in our muscles, headache, upset stomach, racing heartbeat, deep sighing or shallow breathing. Others may experience them as emotional or psychological symptoms such as anxiety, poor concentration, depression, hopelessness, frustration, anger, sadness or fear.

Excess stress does not always show up as the “feeling” of being stressed. Many stresses go directly into our physical body and may only be recognized by the physical symptoms we manifest. Two excellent examples of stress induced conditions are “eye twitching” and “teeth-grinding.” Conversely, we may “feel” lots of emotional stress in our emotional body and have very few physical symptoms or signs in our body.

By recognizing the symptoms and signs of being in fight or flight, we can begin to take steps to handle the stress overload. There are benefits to being in fight or flight—even when the threat is only psychological rather than physical. For example, in times of emotional jeopardy, the fight or flight response can sharpen our mental acuity, thereby helping us deal decisively with issues, moving us to action. But it can also make us hypervigilant and over-reactive during times when a state of calm awareness is more productive. By learning to recognize the signals of fight or flight activation, we can avoid reacting excessively to events and fears that are not life threatening. In so doing, we can play “emotional judo” with our fight or flight response, “using” its energy to help us rather than harm us. We can borrow the beneficial effects (heightened awareness, mental acuity and the ability to tolerate excess pain) in order to change our emotional environment and deal productively with our fears, thoughts and potential dangers.

Advertisements

Fertilization Process in Humans…

The lucky few sperm who reached the egg in the Fallopian tube surround it and begin competing for entrance. The head of each sperm, the acrosome, releases enzymes that begin to break down the outer, jelly-like layer of the egg’s membrane, trying to penetrate the egg. Once a single sperm has penetrated, the cell membrane of the egg changes its electrical characteristics. This electrical signal causes small sacs just beneath the membrane (cortical granules) to dump their contents into the space surrounding the egg. The contents swell, pushing the other sperm far away from the egg in a process called cortical reaction. The cortical reaction ensures that only one sperm fertilizes the egg. The other sperm die within 48 hours.

The fertilized egg is now called a zygote. The depolarization caused by sperm penetration results in one last round of division in the egg’s nucleus, forming a pronucleus containing only one set of genetic information. The pronucleus from the egg merges with the nucleus from the sperm. Once the two pronuclei merge, cell division begins immediately.

The dividing zygote gets pushed along the Fallopian tube. Approximately four days after fertilization, the zygote has about 100 cells and is called a blastocyst. When the blastocyst reaches the uterine lining, it floats for about two days and finally implants itself in the uterine wall around six days after fertilization. This signals the beginning of pregnancy. The implanted blastocyst continues developing in the uterus for nine months. As the baby grows, the uterus stretches until it’s about the size of a basketball. Watch this amazing video……..

Double Fertilization and Triple Fusion..

ScreenHunter_01 Sep. 19 16.25

Double Fertilization is a complex fertilization mechanism that has evolved in flowering plants (angiosperms). This process involves the joining of a female gametophyte (megagametophyte, also called the embryo sac) with two male gametes (sperm). It begins when a pollen grain adheres to the stigma of the carpel, the female reproductive structure of a flower. The pollen grain then takes in moisture and begins to germinate, forming a pollen tube that extends down toward the ovary through the style. The tip of the pollen tube then enters the ovary and penetrates through the micropyle opening in the ovule. The pollen tube proceeds to release the two sperm in the megagametophyte.

One sperm fertilizes the egg cell and the other sperm combines with the two polar nuclei of the large central cell of the megagametophyte. The haploid sperm and haploid egg combine to form a diploid zygote, while the other sperm and the two haploid polar nuclei of the large central cell of the megagametophyte form a triploid nucleus (some plants may form polyploid nuclei). The large cell of the gametophyte will then develop into the endosperm, a nutrient-rich tissue which provides nourishment to the developing embryo. The ovary, surrounding the ovules, develops into the fruit, which protects the seeds and may function to disperse them.

Easy way to Understand Mensuration Cycle…….

ImageMenstrual cycle is the cycle of changes that occurs in the uterus and ovary for the purpose of sexual reproduction. It is essential for the production of eggs and for the preparation of the uterus for pregnancy.The menstrual cycle occurs only in fertile female humans and other female primates.

In humans, the length of a menstrual cycle varies greatly among women (ranging from 25 to 35 days), with 28 days designated as the average length. Each cycle can be divided into three phases based on events in the ovary (ovarian cycle) or in the uterus (uterine cycle).  The ovarian cycle consists of the follicular phase, ovulation, and luteal phase whereas the uterine cycle is divided into menstruation, proliferative phase, and secretory phase. Both cycles are controlled by the endocrine system and the normal hormonal changes that occur can be interfered with using hormonal contraception to prevent reproduction.

By convention, menstrual cycles are counted from the first day of menstrual bleeding. Stimulated by gradually increasing amounts of estrogen in the follicular phase, discharges of blood (menses) slow then stop, and the lining of the uterus thickens. Follicles in the ovary begin developing under the influence of a complex interplay of hormones, and after several days one or occasionally two become dominant (non-dominant follicles atrophy and die). Approximately mid-cycle, 24–36 hours after the Luteinizing Hormone (LH) surges, the dominant follicle releases an ovum, or egg in an event called ovulation. After ovulation, the egg only lives for 24 hours or less without fertilization while the remains of the dominant follicle in the ovary become a corpus luteum; this body has a primary function of producing large amounts of progesterone. Under the influence of progesterone, the endometrium (uterine lining) changes to prepare for potential implantation of an embryo to establish a pregnancy. If implantation does not occur within approximately two weeks, the corpus luteum will involute, causing sharp drops in levels of both progesterone and estrogen. These hormone drops cause the uterus to shed its lining and egg in a process termed menstruation.

In the menstrual cycle, changes occur in the female reproductive system as well as other systems (which lead to breast tenderness or mood changes, for example). A woman’s first menstruation is termed menarche, and occurs typically around age 12-13. The end of a woman’s reproductive phase is called the menopause, which commonly occurs somewhere between the ages of 45 and 55.

Insertion of Pacemaker ……..

What is a pacemaker?

A pacemaker is composed of three parts: a pulse generator, one or more leads, and an electrode on each lead. A pacemaker signals the heart to beat when the heartbeat is too slow or irregular.

A pulse generator is a small metal case that contains electronic circuitry with a small computer and a battery that regulate the impulses sent to the heart.

The lead (or leads) is an insulated wire that is connected to the pulse generator on one end, with the other end placed inside one of the heart’s chambers. The lead is almost always placed so that it runs through a large vein in the chest leading directly to the heart. The electrode on the end of a lead touches the heart wall. The lead delivers the electrical impulses to the heart. It also senses the heart’s electrical activity and relays this information back to the pulse generator. Pacemaker leads may be positioned in the atrium (upper chamber) or ventricle (lower chamber) or both, depending on the medical condition.

If the heart’s rate is slower than the programmed limit, an electrical impulse is sent through the lead to the electrode and causes the heart to beat at a faster rate.

When the heart beats at a rate faster than the programmed limit, the pacemaker generally monitors the heart rate and will not pace. Modern pacemakers are programmed to work on demand only, so they do not compete with natural heartbeats. Generally, no electrical impulses will be sent to the heart unless the heart’s natural rate falls below the pacemaker’s lower limit.

A newer type of pacemaker, called a biventricular pacemaker, is currently used in the treatment of specific types of heart failure. Sometimes in heart failure, the two ventricles do not pump in a normal manner. Ventricular dyssynchrony is a common term used to describe this abnormal pumping pattern. When this happens, less blood is pumped by the heart. A biventricular pacemaker paces both ventricles at the same time, increasing the amount of blood pumped by the heart. This type of treatment is called cardiac resynchronization therapy or CRT.

After a pacemaker insertion, regularly scheduled appointments will be made to ensure the pacemaker is functioning properly. The doctor uses a special computer, called a programmer, to review the pacemaker’s activity and adjust the settings when needed.

Other related procedures that may be used to assess the heart include resting and exercise electrocardiogram (ECG), Holter monitor, signal-averaged ECG, cardiac catheterization, chest X-ray, computed tomography (CT scan) of the chest, echocardiography, electrophysiology studies, magnetic resonance imaging (MRI) of the heart, myocardial perfusion scans, radionuclide angiography, and cardiac CT scan. Please see these procedures for additional information. Note that although an MRI is a very safe procedure, a person with a pacemaker generally should not undergo MRI, as the magnetic fields used by the MRI scanner may interfere with the pacemaker’s function. Any patient with a pacemaker should always speak with his or her cardiologist before undergoing an MRI.
Reasons for the procedure

A pacemaker may be inserted in order to stimulate a faster heart rate when the heart is beating too slowly, and causing problems that cannot otherwise be corrected.

Problems with the heart rhythm may cause difficulties because the heart is unable to pump an adequate amount of blood to the body. If the heart rate is too slow, the blood is pumped too slowly. If the heart rate is too fast or too irregular, the heart chambers are unable to fill up with enough blood to pump out with each beat. When the body does not receive enough blood, symptoms such as fatigue, dizziness, fainting, and/or chest pain may occur.

Some examples of heart rate and rhythm problems for which a pacemaker might be inserted include:

Bradycardia. This occurs when the sinus node causes the heart to beat too slowly.

Tachy-brady syndrome. This is characterized by alternating fast and slow heartbeats.

Heart block. This occurs when the electrical signal is delayed or blocked after leaving the SA node; there are several types of heart blocks.

There may be other reasons for your doctor to recommend a pacemaker insertion.

Physiology of Hearing

Introduction
The physiology of our hearing mechanism can conveniently be divided into three topics:

1 The outer ear (auricle or pinna) and ear canal
2 The middle ear
3 The inner ear

The Auricle and Ear Canal.
Each hole in the side of the skull leads into an ear canal. The ear canal is an irregular cylinder with an average diameter of less than 0.8 mm and about 2.5 cm long.

The ear canal (figure 1) is open at the outer end which is surrounded by the pinna (or auricle). The pinna plays an important spacial focusing role in hearing. The canal then narrows slightly and widens towards its inner end, which is sealed off by the eardrum.

Thus the canal is a shaped tube enclosing a resonating column of air – with the combination of open and closed ends. This makes it rather like an organ pipe.
THE EAR CANAL. [Rigden, 1960]

The ear canal supports (resonates or enhances) sound vibrations best at the frequencies which the human ears hear most sharply. This resonance amplifies the variations of air pressure that make up sound waves, placing a peak pressure directly at the eardrum.

For frequencies between approximately 2 KHz and 5.5 KHz, the sound pressure level at the eardrum is approximately 10 times the pressure of the sound at the auricle.

The Eardrum – interface between outer and middle ear.
Airborne sound waves reach only as far as the eardrum. Here they are converted into mechanical vibrations in the solid materials of the middle ear.

Sounds (air pressure waves) first set up sympathetic vibrations in the taunt membrane of the eardrum, just as they do in the diaphragm of some types of microphone. The eardrum passes these vibrations on to the middle ear structure.
The Middle Ear Ossicular Chain – Malleus (Hammer) , Incus (Anvil) , and Stapes (Stirrup).

The middle ear contains three small bones known as the Malleus, Incus, and Stapes. (Fig. 2). These bones form a system of levers which are linked together and driven by the eardrum. Malleus pushing Incus, Incus pushing Stapes.
The Malleus, Incus, and Stapes.
Working together as a lever system, the bones amplify the force of sound vibrations.
The inner end of the lever moves through a shorter distance but exerts a greater force than the outer end.

In combination the bones double or triple the force of the vibrations at the eardrum.

The muscles of the middle ear modify the performance of this lever system as an amplifying unit. They act as safety devices to protect the ear against excessively large vibrations from very loud sounds – a sort of automatic volume control.

Although these tiny muscles – the smallest in the human body – at both ends of the ossicular chain can be moved voluntarily, their normal contractions are reflex triggered when sound exceeds a certain level. As the noise level rises, one set of muscles tightens to restrict the movement of the malleus thus weakening the vibrations transmitted within the middle ear. At the same time the stapes muscle contracts to pull the stapes away from the oval window so that less vibration is passed along to the very sensitive inner ear.

The Oval Window – Interface Between Middle & Inner Ear.
The stirrup passes the vibrations to the “oval window” which is a membrane covering an opening in the bony case of the cochlea.

The size of the oval window compared to that of the eardrum (15 to 30 times smaller) produces the critical amplification needed to match impedances between sound waves in the air and in the cochlear fluid. Apart from the amplification of the bone lever system of the middle ear, this concentration of force amplifies the incoming vibrations of sound about 15 to 30 times.

Summary of the Amplifications from Outer to Inner Ear.
Within the 4 cm or so occupied by the outer and middle ears, three distinct physical principles operate to magnify weak vibrations in air so that they can establish pressure waves in a liquid:

1 The organ pipe resonance of the ear canal may increase the air pressure fore 10 times.
2 The mechanical advantages of the bone lever system may nearly triple it.
3 The pinpointing arrangement of the eardrum and the oval window may provide another thirty fold increase.

The result of these three mechanisms may be an amplification of a sound wave by more than 800 times before it sets the liquid of the inner ear in motion.