Search results
Results from the WOW.Com Content Network
This has the effect of dephasing the signal emitted in this domain, causing destructive interference in the observed MR signal. Therefore, greater amounts of deoxyhemoglobin lead to less signal. Neuronal activity ultimately leads to an increase in local MR signaling corresponding to a decrease in the concentration of deoxyhemoglobin.
Central nervous system fatigue, or central fatigue, is a form of fatigue that is associated with changes in the synaptic concentration of neurotransmitters within the central nervous system (CNS; including the brain and spinal cord) which affects exercise performance and muscle function and cannot be explained by peripheral factors that affect muscle function.
Environmental factors, internal or external stimuli, continually disrupt homeostasis; an organism's present condition is a state of constant flux moving about a homeostatic point that is that organism's optimal condition for living. [27] Factors causing an organism's condition to diverge too far from homeostasis can be experienced as stress.
Muscle fatigue is when muscles that were initially generating a normal amount of force, then experience a declining ability to generate force. It can be a result of vigorous exercise , but abnormal fatigue may be caused by barriers to or interference with the different stages of muscle contraction .
By homeostasis, Cannon meant "the maintenance of steady states in the body and the physiological processes through which they are regulated." [30] In other words, the body's ability to regulate its internal environment. William Beaumont was the first American to utilize the practical application of physiology.
Fatigue in a medical context is used to cover experiences of low energy that are not caused by normal life. [2] [3]A 2021 review proposed a definition for fatigue as a starting point for discussion: "A multi-dimensional phenomenon in which the biophysiological, cognitive, motivational and emotional state of the body is affected resulting in significant impairment of the individual's ability to ...
Very few animals (e.g. axolotls and sloths) have impaired thyroid homeostasis that exhibits a very low set-point that is assumed to underlie the metabolic and ontogenetic anomalies of these animals. The pituitary gland secretes thyrotropin (TSH; Thyroid Stimulating Hormone) that stimulates the thyroid to secrete thyroxine (T4) and, to a lesser ...
Fluid balance is an aspect of the homeostasis of organisms in which the amount of water in the organism needs to be controlled, via osmoregulation and behavior, such that the concentrations of electrolytes (salts in solution) in the various body fluids are kept within healthy ranges.