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List Of Reflexes (alphabetical)
A list of reflexes in humans. *Abdominal reflex *Accommodation reflex — coordinated changes in the vergence, lens shape and pupil size when looking at a distant object after a near object. *Acoustic reflex or attenuation reflex — contraction of the stapedius and tensor tympani muscles in the middle ear in response to high sound intensities. *Anal wink - contraction of the external anal sphincter upon stroking of the skin around the anus. * Ankle jerk reflex — jerking of the ankle when the Achilles tendon is hit with a tendon hammer while the foot is relaxed, stimulating the S1 reflex arc. * Arthrokinetic reflex — muscular activation or inhibition in response to joint mobilization * Asymmetric tonic neck reflex (ATNR) or tonic neck reflex a primitive reflex— in infants up to four months of age, when the head is turned to the side, the arm on that side will straighten and the contralateral arm will bend. *Babinski reflex — in infants up to one year of age, and also in ol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reflexes
In biology, a reflex, or reflex action, is an involuntary, unplanned sequence or action and nearly instantaneous response to a Stimulus (physiology), stimulus. Reflexes are found with varying levels of complexity in organisms with a nervous system. A reflex occurs via Neural pathway, neural pathways in the nervous system called Reflex arc, reflex arcs. A stimulus initiates a neural signal, which is carried to a synapse. The signal is then transferred across the synapse to a motor neuron which evokes a target response. These neural signals do not always travel to the brain, so many reflexes are an automatic response to a stimulus that does not receive or need conscious thought. Many reflexes are fine-tuned to increase organism survival and self-defense. This is observed in reflexes such as the Startle response, startle reflex, which provides an automatic response to an unexpected stimuli, and the feline righting reflex, which reorients a cat's body when falling to ensure safe l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brain's Reflex
Brain's reflex is the extension of a hemiplegic flexed arm when a quadrupedal posture is assumed by a human subject. It was first described by Russell Brain, a British neurologist Neurology (from el, νεῦρον (neûron), "string, nerve" and the suffix -logia, "study of") is the branch of medicine dealing with the diagnosis and treatment of all categories of conditions and disease involving the brain, the spinal c ....''Encyclopædia Britannica'' References Reflexes {{med-sign-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enterogastric Reflex
The enterogastric reflex is one of the three extrinsic reflexes of the gastrointestinal tract, the other two being the gastroileal reflex and the gastrocolic reflex. The enterogastric reflex is stimulated by duodenal distension. It can also be stimulated by a pH of 3-4 in the duodenum and by a pH of 1.5 in the stomach. Upon initiation of the reflex, the release of gastrin by G-cells in the antrum of the stomach is shut off. This in turn inhibits gastric motility and the secretion of gastric acid ( HCl). __TOC__ Emptying inhibitory factors The stomach's contents are inhibited from emptying into the small intestine by: * duodenadistensionref name=encycom> * duodenal acidic pH * duodenal hypertonicity * increased osmolarity Osmotic concentration, formerly known as osmolarity, is the measure of solute concentration, defined as the number of osmoles (Osm) of solute per litre (L) of solution (osmol/L or Osm/L). The osmolarity of a solution is usually expressed as Osm/L ... of g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diving Reflex
The diving reflex, also known as the diving response and mammalian diving reflex, is a set of physiological responses to immersion that overrides the basic homeostatic reflexes, and is found in all air-breathing vertebrates studied to date. It optimizes respiration by preferentially distributing oxygen stores to the heart and brain, enabling submersion for an extended time. The diving reflex is exhibited strongly in aquatic mammals, such as seals, otters, dolphins, and muskrats, and exists as a lesser response in other animals, including human babies up to 6 months old (see infant swimming), and diving birds, such as ducks and penguins. Adult humans generally exhibit a mild response, the dive-hunting Sama-Bajau people being a notable outlier. The diving reflex is triggered specifically by chilling and wetting the nostrils and face while breath-holding, and is sustained via neural processing originating in the carotid chemoreceptors. The most noticeable effects are on the cardiov ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cushing Reflex
Cushing reflex (also referred to as the vasopressor response, the Cushing effect, the Cushing reaction, the Cushing phenomenon, the Cushing response, or Cushing's Law) is a physiological nervous system response to increased intracranial pressure (ICP) that results in Cushing's triad of increased blood pressure, irregular breathing, and bradycardia. It is usually seen in the terminal stages of acute head injury and may indicate imminent brain herniation. It can also be seen after the intravenous administration of epinephrine and similar drugs. It was first described in detail by American neurosurgeon Harvey Cushing in 1901. Definition The Cushing reflex classically presents as an increase in systolic and pulse pressure, reduction of the heart rate ( bradycardia), and irregular respiration. It is caused by increased pressure inside the skull. These symptoms can be indicative of insufficient blood flow to the brain ( ischemia) as well as compression of arterioles. In response to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crossed Extensor Reflex
The crossed extensor reflex or crossed extensor response or crossed extension reflex is a reflex in which the contralateral limb compensates for loss of support when the ipsilateral limb withdraws from painful stimulus in a withdrawal reflex. During a withdrawal reflex, the flexors in the withdrawing limb contract and the extensor In anatomy, extension is a movement of a joint that increases the angle between two bones or body surfaces at a joint. Extension usually results in straightening of the bones or body surfaces involved. For example, extension is produced by extendin ...s relax, while in the other limb, the opposite occurs as part of the crossed extensor reflex. Besides shifting the body weight to the other side, the reflex pathway is also associated with leg coordination when walking by flexing muscle on one side, while extending muscle on the other side. This crossed extensor response is properly part of the withdrawal reflex. An example of this is when a person steps on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cremasteric Reflex
The cremasteric reflex is a superficial (i.e., close to the skin's surface) reflex observed in human males. This reflex is elicited by lightly stroking or poking the superior and medial (inner) part of the thigh—regardless of the direction of stroke. The normal response is an immediate contraction of the cremaster muscle that pulls up the testis ipsilaterally (on the same side of the body). The reflex utilizes sensory and motor fibers from two different nerves. When the inner thigh is stroked, sensory fibers of the ilioinguinal nerve are stimulated. These activate the motor fibers of the genital branch of the genitofemoral nerve which causes the cremaster muscle to contract and elevate the testis. Clinical conditions In boys, this reflex may be exaggerated which can occasionally lead to a misdiagnosis of cryptorchidism. The cremasteric reflex may be absent with testicular torsion, upper and lower motor neuron disorders, as well as a spine injury of L1-L2. It can also occur if ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cough Reflex
The cough reflex occurs when stimulation of cough receptors in the respiratory tract by dust or other foreign particles produces a cough, which causes rapidly moving air which usually remove the foreign material before it reaches the lungs. This typically clears particles from the bronchi and trachea, the tubes that feed air to lung tissue from the nose and mouth. The larynx (voice box) and carina (at the bottom of the trachea, as it splits into bronchi) are especially sensitive. Cough receptors in the surface cells ( epithelium) of the respiratory tract are also sensitive to chemicals. Terminal bronchioles and even the alveoli are sensitive to chemicals such as sulfur dioxide gas or chlorine gas. Physiology of cough The cough receptors or rapidly adapting irritant receptors are located mainly on the posterior wall of the trachea, pharynx, and at the carina of trachea, the point where the trachea branches into the main bronchi. The receptors are less abundant in the distal airway ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coronary Reflex
Coronary reflex is the change of coronary diameter in response to chemical, neurological or mechanical stimulation of the coronary arteries. The coronary reflexes are stimulated differently from the rest of the vascular system. Causes of coronary constriction Chemical * N-nitro L-arginine * indomethacin * glibenclamide * tetraethylammonium chloride * caffeine Other * Cold Causes of coronary dilation Cocaine abuse frequently can cause a coronary spasm, resulting in a spontaneous myocardial infarction A myocardial infarction (MI), commonly known as a heart attack, occurs when blood flow decreases or stops to the coronary artery of the heart, causing damage to the heart muscle. The most common symptom is chest pain or discomfort which may .... Chemical * Versed (Midazolam): a coronary dilator. In midazolam's presence, dilation was unaffected by N-nitro L-arginine, indomethacin and glibenclamide. * Tetraethylammonium chloride, an inhibitor of the BKCa K+ channel (a high cond ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corneal Reflex
The corneal reflex, also known as the blink reflex or eyelid reflex, is an involuntary blinking of the eyelids elicited by stimulation of the cornea (such as by touching or by a foreign body), though it could result from any peripheral stimulus. Stimulation should elicit both a direct and consensual response (response of the opposite eye). The reflex occurs at a rapid rate of 0.1 seconds. The purpose of this reflex is to protect the eyes from foreign bodies and bright lights (the latter known as the optical reflex). The blink reflex also occurs when sounds greater than 40–60 dB are made. The reflex is mediated by: * the nasociliary branch of the ophthalmic branch (V1) of the trigeminal nerve (CN V) sensing the stimulus on the cornea only (afferent fiber). * the temporal and zygomatic branches of the facial nerve (CN VII) initiating the motor response (efferent fiber). * the center (nucleus) is located in the pons of the brainstem. Use of contact lenses may diminish or ab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Churchill–Cope Reflex
The Churchill–Cope reflex is a reflex in which distension of the pulmonary vascular bed, as occurs in pulmonary edema, causes an increase in respiratory rate (tachypnoea Tachypnea, also spelt tachypnoea, is a respiratory rate greater than normal, resulting in abnormally rapid and shallow breathing. In adult humans at rest, any respiratory rate of 1220 per minute is considered clinically normal, with tachypnea be ...) by stimulation of the juxtacapillary (J) receptors. It was described in 1929 by Edward Delos Churchill and Oliver Cope.Churchill ED, Cope O. The rapid shallow breathing resulting from pulmonary congestion and edema. ''J Exp Med'' 1929; 49:531-537Full text/ref> References Cardiovascular physiology Reflexes {{circulatory-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
