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Information about Reflex

ReFLEX is a wireless protocol developed by Motorola which is used for two-way paging. It is based on the one-way FLEX protocol and comes in two variants, ReFLEX25 and ReFLEX50. Later version 2.7 of the ReFLEX protocol was released. Devices compliant with ReFLEX 2.7.x can operate on both ReFLEX25 and ReFLEX50 networks.

The Motorola PageWriter released in 1996 was one of the first devices to use the ReFLEX network protocol.
For reflexive language, see reflexive pronoun and reflexive verb.


A reflex action is an automatic (involuntary) neuromuscular action elicited by a defined stimulus.[1] In most contexts, especially involving humans, a reflex action is mediated via the reflex arc (although this is not always true in other animals, or in more casual usage of the term 'reflex'.)

Mechanism

A reflex action or reflex is a biological control system linking stimulus to response and mediated by a reflex arc. Reflexes can be built-in or learnt. For example, a person stepping on a sharp object would initiate the reflex action through the creation of a nociceptive stimulus within specialized sense receptors located in the skin tissue of the foot. The resulting stimulus would be transmitted through an afferent nerve to the spinal cord. This stimulus is usually processed by an interneuron to create an immediate response to nociception by initiating a motor response to withdraw from the pain-producing object. This retraction would occur as the sensation is arriving in the brain and producing the subjective perception of pain, which would result in a more cognitive evaluation of the situation.

Reflexes are tested as part of a neurological examination to assess damage to or functioning of the central and peripheral nervous system.

Reflexes may be trained, such as during repetition of motor actions during sport practice, or the linking of stimuli with autonomic reactions during classical conditioning.

Reaction time

For a reflex, reaction time or latency is the time from the onset of a stimulus until the organism responds.

In humans, reaction time to visual stimuli is typically 150 to 300 milliseconds.[2]

Human reflexes

Enlarge picture
The mechanism of the reflex arc. Note that this image includes an interneuron in the monosynaptic patellar reflex for purposes of illustration.
Reflex actions include:

Tendon reflexes and stretch reflexes

The deep tendon reflexes provide information on the integrity of the central and peripheral nervous system. Generally, decreased reflexes indicate a peripheral problem, and lively or exaggerated reflexes a central one. While the reflexes above are stimulated mechanically, the term H-reflex refers to the analogous reflex stimulated electrically, and Tonic vibration reflex for those stimulated by vibration.

Reflexes involving cranial nerves

NameSensoryMotor
Pupillary reflexIIIII
Accommodation reflexIIIII
Corneal reflex, also known as the blink reflexVVII
Caloric reflex test/Vestibulo-ocular reflexVIIIIII, IV, VI +
Gag reflexIXX

Reflexes in infants only

Main article: Primitive reflexes
Enlarge picture
grasp reflex
Newborn babies have a number of other reflexes which are not seen in adults, referred to as primitive reflexes.[3] These include:

Other reflexes

Other reflexes found in the human nervous system include: Processes such as breathing, digestion, and the maintenance of the heartbeat can also be regarded as reflex actions, according to some definitions of the term.

See also

References

1. ^ Purves (2004). Neuroscience: Third Edition. Massachusetts, Sinauer Associates, Inc.
2. ^ Human Benchmark: Reaction Time Statistics. Retrieved on 2007-10-11.
3. ^ NIC27 at FPnotebook
Motorola Inc.

Public (NYSE: MOT )
Founded 1928
Headquarters Schaumburg, Illinois, USA

Key people Edward Zander, CEO & Chairman
Industry Telecommunications
Products Embedded systems
Microprocessors
Mobile phones
Two-Way radios
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FLEX is a communication protocol developed by Motorola and used in many pagers. FLEX provides one-way communication only (from the provider to the pager device), but a related protocol called ReFLEX provides two-way messaging.
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reflexive pronoun is a pronoun that is preceded by the noun or pronoun to which it refers (its antecedent) within the same clause. In generative grammar, a reflexive pronoun is an anaphor that must be bound by its antecedent (see binding).
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In grammar, a reflexive verb is a verb whose semantic agent and patient (typically represented syntactically by the subject and the direct object) are the same. For example, the English verb to perjure is reflexive, since one can only perjure oneself.
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In physiology, a stimulus is a detectable change in the internal or external environment. When a stimulus is applied to a sensory receptor, it elicits or influences a reflex via stimulus transduction. A stimulus is often the first component of a homeostatic control system.
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reflex arc is the neural pathway that mediates a reflex action. In higher animals, most sensory neurons do not pass directly into the brain, but synapse in the spinal cord.
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In military aviation, a Control system is frequently used in place of a Ground Control Station when describing an Unmanned Aircraft System control element which may be located anywhere, not just on the ground.
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Stimulation is the action of various agents (stimuli) on muscles, nerves, or a sensory end organ, by which activity is evoked; especially, the nervous impulse produced by various agents on nerves, or a sensory end organ, by which the part connected with the nerve is thrown into a
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A response is the following:
  • Often a response is the result of a stimulus.
  • Usually a response is a reply to a query.
  • In data transmission, a response is the content of the control field of a response frame advising the primary station concerning the processing by

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reflex arc is the neural pathway that mediates a reflex action. In higher animals, most sensory neurons do not pass directly into the brain, but synapse in the spinal cord.
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Pain is a sensation transmitted from sensory nerves through the spinal cord and to the sensory area of the cerebrum, where the sensation is perceived. It is defined by the International Association for the Study of Pain (IASP) as “an unpleasant sensory and emotional
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In physiology, a stimulus is a detectable change in the internal or external environment. When a stimulus is applied to a sensory receptor, it elicits or influences a reflex via stimulus transduction. A stimulus is often the first component of a homeostatic control system.
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afferent neurons--otherwise known as sensory or receptor neurons--carry nerve impulses from receptors or sense organs toward the central nervous system. This is the case vice versa as well. This term can also be used to describe relative connections between structures.
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spinal chord is a thin, tubular bundle of nerves that is an extension of the central nervous system from the brain and is enclosed in and protected by the bony vertebral column.
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An interneuron (also called relay neuron, association neuron or bipolar neuron) is a term used to describe a neuron which has two different common meanings.
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A muscle contraction (also known as a muscle twitch or simply twitch) occurs when a muscle fiber generates tension through the action of actin and myosin cross-bridge cycling. While under tension, the muscle may lengthen, shorten or remain the same.
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Cognition is a diffuse term, used in different ways by different disciplines. In psychology, it refers to an information processing view of an individual's psychological functions.
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The neurological examination is the physical examination of the nervous system. It attempts to identify or exclude signs of nervous system disease, and - if these signs are present - to produce a likely anatomical or physiological explanation that can be tested through medical
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The central nervous system (CNS) represents the largest part of the nervous system, including the brain and the spinal cord. Together with the peripheral nervous system, it has a fundamental role in the control of behavior.
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The Peripheral nervous system resides or extends outside the "CNS" central nervous system (the brain and spinal cord) to serve the limbs and organs. Unlike the central nervous system, however, the PNS is not protected by bone, leaving it exposed to toxins and mechanical injuries.
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autonomic nervous system (ANS) (or visceral nervous system) is the part of the peripheral nervous system that acts as a control system, maintaining homeostasis in the body. These maintenance activities are primarily performed without conscious control or sensation.
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Classical Conditioning (also Pavlovian or Respondent Conditioning) is a form of associative learning that was first demonstrated by Ivan Pavlov. The typical procedure for inducing classical conditioning involves presentations of a neutral stimulus along with a
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For Ian Lowe's book, see Reaction Time (book).


Reaction time (RT) is the elapsed time between the presentation of a sensory stimulus and the subsequent behavioral response.
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Plantae
  • Chromalveolata
  • Heterokontophyta
  • Haptophyta
  • Cryptophyta
  • Alveolata

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    If you are prevented from editing this page, and you wish to make a change, please discuss changes on the talk page, request unprotection, log in, or .
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    Vision may mean:
    • Visual perception via the visual system; one of the senses
    • Computer vision, a field of artificial intelligence
    • Vision (religion), inspirational renderings believed to come from a deity
    • A visual or generic hallucination

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    Tendon reflex (or T-reflex) is a feedback mechanism that controls increasing muscle tension by causing muscle relaxation before tension force becomes so great it may damage the muscle.
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    A stretch reflex is a muscle contraction in response to stretching within the muscle. It is a monosynaptic reflex which provides automatic regulation of skeletal muscle length.

    Muscle spindles are sensory apparatus sensitive to stretch of the muscle in which they lie.
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    A reflex test that examines the function of the C5 reflex arc and to a lesser degree the C6 reflex arc. The test is performed by using of a tendon hammer to quickly depress the biceps brachii tendon as it passes through the cubital fossa.
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    The tricep reflex is tested as part of the neurological examination to asses the sensory and motor pathways within the C7 and C8 spinal nerves. The triceps reflex originates from the triceps brachii muscle, and is initiated by the C7 nerve root.
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