How to Talk to Anyone (Junior Talker #4), DeYtH Banger [ebook reader screen .txt] 📗
- Author: DeYtH Banger
Book online «How to Talk to Anyone (Junior Talker #4), DeYtH Banger [ebook reader screen .txt] 📗». Author DeYtH Banger
There are two types of lymphocytes:
B cells- produce antibodies which are released into the fluid surrounding the body’s cells to destroy the invading viruses and bacteria.
T cells (see picture opposite) - if the invader gets inside a cell, these (T cells) lock on to the infected cell, multiply and destroy it.
The main types of immune cells are white blood cells. There are two types of white blood cells – lymphocytes and phagocytes.
When we’re stressed, the immune system’s ability to fight off antigens is reduced. That is why we are more susceptible to infections.
The stress hormone corticosteroid can suppress the effectiveness of the immune system (e.g. lowers the number of lymphocytes).
Stress can also have an indirect effect on the immune system as a person may use unhealthy behavioral coping strategies to reduce their stress, such as drinking and smoking.
Stress is linked to: headaches; infectious illness (e.g. ‘flu); cardiovascular disease; diabetes, asthma and gastric ulcers.
Stress and Illness
Stress responses have an effect on digestive system. During stress digestion is inhibited. After stress digestive activity increases. This may affect the health of digestive system and cause ulcers. Adrenaline released during a stress response may also cause ulcers.
Stress responses increase strain upon circulatory system due to increased heart rate etc. Stress can also affect the immune system by raising blood pressure.
Hypertension (consistently raised blood pressure over several weeks) is a major risk factor in coronary heart disease (CHD) However, CHD may be caused by eating too much salt, drinking too much coffee or alcohol.
Stress also produces an increase in blood cholesterol levels, through the action of adrenaline and noradrenaline on the release of free fatty acids. This produces a clumping together of cholesterol particles, leading to clots in the blood and in the artery walls and occlusion of the arteries.
In turn, raised heart rate is related to a more rapid build-up of cholesterol on artery walls. High blood pressure results in small lesions on the artery walls, and cholesterol tends to get trapped in these lesions (Holmes, 1994).
Stress can also have an indirect effect on illness as it is associated with all manner of bad habits (coping strategies), for example smoking, drinking alcohol to excess, poor diet due to lack of time, lack of exercise for the same reason, lack of sleep etc.
All of these are likely to have an adverse effect on a person’s health so could cause some of the ill-effects attributed to stress per se.
Stress and Immune Function
Short term suppression of the immune system is not dangerous. However, chronic suppression leaves the body vulnerable to infection and disease.
A current example of this is AIDS - Acquired immune deficiency syndrome. Here the immune system is suppressed leaving the vulnerable to illness. Stress would just lead to frequent illness and infections.
Stress responses increase strain upon circulatory system due to increased heart rate etc. This may increase a person’s risk of developing disorders of the heart and circulation e.g. coronary heart disease (CHD). Individuals with type A personality have a greater risk of developing CHD.
Stress responses have an effect on digestive system. During stress digestion is inhibited. After stress digestive activity increases. This may affect the health of digestive system and cause gastric ulcers
The executive monkey study by Brady (1958) seems to support this theory.
Kiecolt-Glaser et al., (1984)
Aim: To investigate whether stress of important examinations has an effect on the functioning of the immune system
Procedure:
This was a natural experiment. The researchers took blood samples from 75 first year medical students (49 males and 26 females), all of whom were volunteers.
Blood samples were taken: (a) one month before their final examinations (relatively low stress), and (b) during the examinations (high stress)
Immune functioning was assessed by measuring T cell activity in the blood samples.
The students were also given questionnaires to assess psychological variables such as life events and loneliness.
Findings: The blood sample taken from the first group (before the exam) contained more t-cells compared with blood samples taken during the exams.
The volunteers were also assessed using behavioral measures. On both occasions they were given questionnaires to assess psychiatric symptoms, loneliness and life events. This was because there are theories which suggest that all 3 are associated with increased levels of stress.
Kiecolt-Glaser et al found that immune responses were especially weak in those students who reported feeling most lonely, as well as those who were experiencing other stressful life events and psychiatric symptoms such as depression or anxiety.
Conclusion: Stress (of the exam) reduced the effectiveness of the immune system
.
Evaluation: Difficult to unravel the relationship for certain. Does stress cause illness or does being ill make you more prone to stress?
Also many of the studies do not take into account for the other factors which affect people’s lives. These can be drugs, alcohol, caffeine, nicotine, general health, diet, physical activity, sleep patterns, age and medication. Although many studies try to control these factors it is very unlikely to gain complete control.
What is the Stress Response?
by Saul McLeod
Stress is a biological and psychological response experienced on encountering a threat that we feel we do not have the resources to deal with.
A stressor is the stimulus (or threat) that causes stress, e.g. exam, divorce, death of loved one, moving house, loss of job.
Sudden and severe stress generally produces:
Increase in heart rate Increase in breathing (lungs dilate) Decrease in digestive activity (don’t feel hungry) Liver released glucose for energy
Firstly, our body judges a situation and decides whether or not it is stressful. This decision is made based on sensory input and processing (i.e. the things we see and hear in the situation) and also on stored memories (i.e. what happened the last time we were in a similar situation).
If the situation is judged as being stressful, the hypothalamus (at the base of the brain) is activated.
The hypothalamus in the brain is in charge of the stress response. When a stress response is triggered, it sends signals to two other structures: the pituitary gland, and the adrenal medulla.
These short term responses are produced by The Fight or Flight Response via the Sympathomedullary Pathway (SAM). Long term stress is regulated by the Hypothalamic Pituitary-Adrenal (HPA) system.
The Hypothalamic Pituitary-Adrenal (HPA) System
The stressor activates the Hypothalamic Pituitary Axis
The hypothalamus stimulates the pituitary gland
The pituitary gland secretes adrenocorticotropic hormone (ACTH)
ACTH stimulates the adrenal glands to produce the hormone corticosteroid
Cortisol enables the body to maintain steady supplies of blood sugar
Adequate and steady blood sugar levels help person to cope with prolonged stressor, and helps the body to return to normal
The adrenal cortex releases stress hormones called cortisol. This have a number of functions including releasing stored glucose from the liver (for energy) and controlling swelling after injury. The immune system is suppressed while this happens.
Sympathomedullary Pathway (SAM)
The hypothalamus also activates the adrenal medulla. The adrenal medulla is part of the autonomic nervous system (ANS).
The ANS is the part of the peripheral nervous system that acts as a control system, maintaining homeostasis in the body. These activities are generally performed without conscious control.
The adrenal medulla secretes the hormone adrenaline. This hormone gets the body ready for a fight or flight response. Physiological reaction includes increased heart rate.
Adrenaline lead to the arousal of the sympathetic nervous system and reduced activity in the parasympathetic nervous system.
Adrenaline creates changes in the body such as decreases (in digestion) and increases (sweating, increased pulse and blood pressure).
Once the ‘threat’ is over the parasympathetic branch takes control and brings the body back into a balanced state.
No ill effects are experienced from the short-term response to stress and it further has survival value in an evolutionary context.
Evaluation
Strengths
Measuring stress hormones gives an objective measure of stress.
Fight/flight response can be seen in all mammals in response to threats.
Weakness
There is considerable variation in level and type of hormones released by different people and in response to different stressors – not a simple physiological process.
People without adrenal glands need hormonal supplements to survive stress.
Symington (1955) found that conscious dying patients showed different stress reactions to unconscious ones. Suggests that psychological factors play a role.
Note: This explains why my behavior is weak...
Critical thinking suppressed in brains of people who believe in the supernatural
The opposition between religious beliefs and scientific evidence can be explained by difference in brain structures and cognitive activity. Scientists have found critical thinking is suppressed in the brains of people who believe in the supernatural.
Published in PLOS One, their study examines how the parts of the brain responsible for empathy and analytical reasoning are linked to faith and spiritual thinking. It suggests religious beliefs and scientific thinking clash because different brain areas are involved in both cognitive processes. People who believe in the supernatural appear to suppress areas associated with critical thinking.
"From what we understand about the brain, the leap of faith to belief in the supernatural amounts to pushing aside the critical/analytical way of thinking...", says lead author Tony Jack, a professor of philosophy at Case Western Reserve.
More empathy, more religion
In previous research, Jack and colleagues had identified, thanks to fMRI scans, two networks of neurones that competed with each other to let individuals see the the world either in religious or in scientific terms. They say the brain has an analytical network of neurons which triggered critical thinking and a social network which enabled empathy towards other and spiritual thinking.
Participants who went through the scans were presented with a physical or ethical problem. To solve it, the brain appeared to boost activity in one of the two networks, while suppressing the other.
For the latest study, the scientists conducted a series of eight experiments, involving between 159 and 527 adults. Their purpose was to compare belief in God with measures of analytic thinking and moral concern.
In each experiment, the researchers found that both spiritual belief and empathic concern were positively associated with frequent religious practice. The more a person was religious, the more he or she is likely to suppress the analytical network in the brain, and to show empathy.
Scientists say that when an individual is conflicted between a scientific or religious view of the world, his brain structures will determine how he will address this opposition between beliefs and science.
Engaging with both networks
The study also points out that some of the great scientists of our times were also very spiritual men. "Far from always conflicting with science, under the right circumstances religious belief may positively promote scientific creativity and insight," says Jack "Many of history's most famous scientists were spiritual or religious. Those noted individuals were intellectually sophisticated enough to see that there is no need for religion and science to come into conflict."
According to the scientists, the individuals who manage to use both networks and avoid suppression of one or the other are better equipped to understand the world and come up with scientific discoveries.
Chapter 12 - God (Truth)
What believing in God does to your brain
Humans suppress areas of the brain used for analytical thinking and engage the parts responsible for empathy in order to believe in god, research suggests.
They do the opposite when thinking
Comments (0)