What are really reflexes?
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A reflex action is a stereotyped (involuntary) motor response elicited by a defined stimulus. 1 A reflex action is mediated via the reflex arc.\n\nA reflex arc is the neural pathway that mediates a reflex. It generally does not involve the brain. In higher animals it is composed of a spinal "reflex integration center" composed of interneurons to connect affector (sensory stimulation) and effector (response) signals. While the reflex generation may be initiated by nociceptive input, extensive processing takes place within the spinal cord. The neural connection from the primary sensory neurons to the motor neurons is a poly-synaptic pathway (Andersen).\n\nIn lower animals reflex interneurons not necessarily inolve the spinal cord, see e.g., lateral giant neuron of crayfish.\n\nA reflex to a stimulus is almost simultaneous, as the reflex arc doesn't involve the brain at all.\nA 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 learned. It occurs very quickly before thinking. Before the message is sent to the brain the spine picks it up and sends it back to the muscle causing spasm.\n\nSimple reflex\nA simple reflex is entirely automatic and involves no learning.\n\nAn example is the escape reflex (e.g., the sudden withdrawal of a hand in response to a pain stimulus), or the patellar reflex (the jerking of a leg when the kneecap is tapped). Sensory cells (receptors) in the stimulated body part send signals to the spinal cord along a sensory nerve cell. Within the spine a reflex arc switches the signals straight back to the muscles of the body (in this case the arm or the leg) (effectors) via an intermediate nerve cell and then a motor nerve cell; contraction of the leg occurs, and the muscle contracts (the arm or leg jerks upwards). Only three nerve cells are involved, and the brain is only aware of the response after it has taken place. Such reflex arcs are particularly common in animals, and have a high survival value, enabling organisms to take rapid action to avoid potential danger.\n\nConditioned reflex\nA conditioned reflex involves the modification of a reflex action in response to experience (learning). A stimulus that produces a simple reflex response becomes linked with another, possibly unrelated, stimulus. For example, a dog may salivate (a reflex action) when it sees its owner remove a tin-opener from a drawer because it has learned to associate that stimulus with the stimulus of being fed.\n\nReaction time\nFor a reflex, reaction time or latency is the time from the onset of a stimulus until the organism
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Reflex responses actually occur in the spinal cord; so the flight reflex, if already triggered (i.e., the chicken sees that axe a'comin') could keep firing even after the brain is no longer in the picture. \n\nThe chicken has a limited amount of time, of course, since it's bleeding out, but during that period, anything that's happening on the reflex level still can happen.\n\nAn old biology experiment (I take that back - after searching, it's apparently still being done) involved essentially cutting off a frog's head in such a manner that there was no brain left, but the spinal cord and peripheral nerves were intact. Said frog would turn itself back over if rolled onto its back, and would jerk its foot away from a shock, demonstrating that the reflexes are handled in the spinal cord, not the brain. (Sorry about your head, pal.)
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Interesting question. Possibly related to our ancestors time in the trees. A strong grip would be essential for survival and this involuntary reflex is a relic from that time.
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During muscle contraction the strands of collagen are stretched as the muscle shortens. This stretching deforms the terminals of the Ib afferent axon, opening stretch-sensitive cation channels. As a result, the axon is depolarized and fires nerve impulses up to the central nervous system via the spinal cord. The action potential frequency signals the force being developed within the muscle.\n\nThis sensory feedback plays an important role in spinal reflexes and in the central control of muscle contraction. Specifically, it is postulated that because a Golgi tendon organ exists in serial connection with muscle fibers, it can measure the tension that each muscle contraction builds up. The Ib afferent axon synapses with interneurons within the spinal cord and also relays information to the brain. One of the main spinal reflexes receiving an input from the Ib afferent is the autogenic inhibition reflex, which is involved with the regulation of the force profile of on-going muscle contractions.\n\nThe ascending pathways to the cerebellum are the dorsal and ventral spinocerebellar tracts and are involved in the cerebellar regulation of movement.
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http://www.ofesite.com/health/reflex/reflex.htm
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That is not a valid question. However, on an average, and in general, Males tend to have better "reflexes".\n\nBut there are many women out there who are better then most males!
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recognize that you're being OC when you are. For example, I had this habit of thinking the front door was unlocked when I left. I KNEW I had locked it but I would have double check EVERY DAY until I realized I was just being obsessive compulsive. Not everything is that simple but if you recognize for what it is when you're doing the (specific action), you can walk your self thru (in your mind) to break your body of the habit.
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A simple was to state it: The sensation that you react to, like a pinprick, or sudden shortening of your tendon (like when you slip) sends a message along the sensory axon.  This communicates with a motorneuron in your spinal cord, which immediately sends a signal to a muscle-so that you jerk your hand back from pain, or move your leg to catch yourself before you fall.  The whole sequence doesnt involve your brain at all, its all done in your spinal cord- a single synapse.
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Pub is sort of correct, although he contradicts himself a bit.\n\nIt is a reflex ... reflexes are learned activities.  Close the door ... turn off the music, etc.  Always do this with quiet concentration.  You will have to retrain your body to accept this new event.\n\nBy minimizing the distractions, you have more focus and control ... be patient, but regular.  You can retrain reflexes.
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It's a reflex to keep snot our of your eyes.
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>>>>>What reflexes do you retain while unconscious?\n\nThat depends on the level of unconsciousness. It isn’t a binary state.  For example a person who is lightly dozing is unconscious, but they are much more responsive to stimuli than a person who is under anaesthetic.  Different reflexes are apparent at each stage.\n\n>>>>Would your eyes still water if something was in them?\nUsually, yes. They eye blink reflex, ie will the eye respond when tapped, is commonly taught as one of the tests for death or total lack of sensation. It’s pretty deeply wired. At the deepest levels of aneasthesia or coma, possibly not. \n\n>>>Would you still kick if your knee was tapped? \n\nIt should do. That reflex has nothing to do with the brain at all and should operate even if the subject is dead.\n\n>>>>>What about after death? Does the knee-jerk reflex still work?\nYes, at least to the point they the muscles and nerves deteriorate beyond function.\n\nZero said “your brain is why you have reflexes in the first place”\n\nNope. \n\nReflexes in the head operate off the brain. But by definition reflexes elsewhere in the body operate off the spinal cord.\n\nEven with reflexes in the hea dit is quite posible to be 'brian dead' and still have operational reflexes. Brain death means the higher brain centres have ceased functioning, some reflex centres can still be responding.
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Just to clear up some mistakes in an otherwise good answer- the fastest reflexes only require two neurons-large myelinated sensory axons can and do directly stimulate motorneurons.  The nervous system that control digestion is the enteric, not entric, and its Eric Kandel, not Kendel, who wrote the Fundamental of Neuroscience....If you are presenting a poster at this years SFN meeting and meet the guy, it might come in handy..
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Being very instinctive. Doing anything the moment it comes to mind without any further thought. Anyone who is impulsive is spontaneous giving an immediate and natural reaction to any situation they are under. Impulsive reactions always expresses what is on the mind on of a person. In todays world most people regret being impulsive.
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Cord mediated...(Simple reflex, no learning) ...Any reflex test ie knee, elbow etc.\nSomatic...(Complex, learned) ..Wihdrawing from heat rapidy, salivating at the smell of dinner cooking.
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Spinal\n\n\n\nErection is basically a spinal reflex that can be initiated by recruitment of penile afferents, but also by visual, olfactory, and imaginary stimuli. The reflex involves both autonomic and somatic efferents and is modulated by supraspinal influences. Several central transmitters involved in the erectile control have been identified. Dopamine, acetylcholine, nitric oxide (NO), and peptides, such as oxytocin and adrenocorticotropic/alpha-melanocyte-stimulating hormone, seem to have a facilitatory role, whereas serotonin may be either facilitatory or inhibitory, and enkephalins are inhibitory.
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The brain is not involved in a reflex arc. I believe the signal only gets as far as the spinal cord. You pull your hand away from a hot stove before your brain can even register that it is feeling heat.
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In cases of extreme fear, the human body releases epinephrine (adrenaline) and shifts blood around your core (to protect organs) and to your brain.  Electrical impulses from the brain are focused on muscles that coordinate movement, and some other functions are deemed "accessory," like contracting the muscles that keep you from urinating or defecating on yourself.  This is to ensure that you can focus all of your energy on "fight or flight."