Stress

Gene may hold key to hearing recovery

Researchers have discovered that a protein implicated in human longevity may also play a role in restoring hearing after noise exposure. The findings, where were published in the journal Scientific Reports, could one day ...

23 hours ago
popularity205 comments 0

Dopamine control of prolactin secretion

In women, a major role of prolactin is to initiate and sustain pregnancy and lactation. During pregnancy, prolactin secretion from the pituitary gland is important for pregnancy maintenance and prolactin levels are correlated ...

1 hour ago
popularity1 comments 0

How brains process facial expressions

Have you ever thought someone was angry at you, but it turned out you were just misreading their facial expression? Caltech researchers have now discovered that one specific region of the brain, called the amygdala, is involved ...

3 hours ago
popularity26 comments 0

Stress is a term that is commonly used today but has become increasingly difficult to define. It shares, to some extent, common meanings in both the biological and psychological sciences. Stress typically describes a negative concept that can have an impact on one’s mental and physical well-being, but it is unclear what exactly defines stress and whether or not stress is a cause, an effect, or the process connecting the two. With organisms as complex as humans, stress can take on entirely concrete or abstract meanings with highly subjective qualities, satisfying definitions of both cause and effect in ways that can be both tangible and intangible.

The term stress had none of its contemporary connotations before the 1920s. It is a form of the Middle English destresse, derived via Old French from the Latin stringere, "to draw tight." It had long been in use in physics to refer to the internal distribution of a force exerted on a material body, resulting in strain. In the 1920s and 1930s, the term was occasionally being used in biological and psychological circles to refer to a mental strain, unwelcome happening, or, more medically, a harmful environmental agent that could cause illness. Walter Cannon used it in 1926 to refer to external factors that disrupted what he called homeostasis.

Homeostasis is a concept central to the idea of stress. In biology, most biochemical processes strive to maintain equilibrium, a steady state that exists more as an ideal and less as an achievable condition. Environmental factors, internal or external stimuli, continually disrupt homeostasis; an organism’s present condition is a state in constant flux wavering about a homeostatic point that is that organism’s optimal condition for living. Factors causing an organism’s condition to waver away from homeostasis can be interpreted as stress. A life-threating situation such as a physical insult or prolonged starvation can greatly disrupt homeostasis. On the other hand, an organism’s effortful attempt at restoring conditions back to or near homeostasis, oftentimes consuming energy and natural resources, can also be interpreted as stress. In such instances, an organism’s fight-or-flight response recruits the body’s energy stores and focuses attention to overcome the challenge at hand. The ambiguity in defining this phenomenon was first recognized by Hans Selye in 1926 who loosely described stress as something that “…in addition to being itself, was also the cause of itself, and the result of itself." First to use the term in a biological context, Selye continued to define stress as “the non-specific response of the body to any demand placed upon it.” Present-day neuroscientists including Bruce McEwen and Jaap Koolhaas believe that stress, based on years of empirical research, “should be restricted to conditions where an environmental demand exceeds the natural regulatory capacity of an organism.” Despite the numerous definitions given to stress, homeostasis appears to lie at its core.

Biology has progressed in this field greatly, elucidating complex biochemical mechanisms that appear to underlie diverse aspects of stress, shining a necessary light on its clinical relevance and significance. Despite this, science still runs into the problem of not being able to settle or agree on conceptual and operational definitions of stress. Because stress is ultimately perceived as a subjective experience, it follows that its definition perhaps ought to remain fluid. For a concept so ambiguous and difficult to define, stress nevertheless plays an obvious and predominant role in the every day lives of humans and nature alike.

This text uses material from Wikipedia licensed under CC BY-SA

Latest Spotlight News

Skin stem cells used to generate new brain cells

Using human skin cells, University of California, Irvine neurobiologists and their colleagues have created a method to generate one of the principle cell types of the brain called microglia, which play a key role in preserving ...

How brains process facial expressions

Have you ever thought someone was angry at you, but it turned out you were just misreading their facial expression? Caltech researchers have now discovered that one specific region of the brain, called the amygdala, is involved ...