question: Why do coughs happen during sleep and not sneezes?
comment: You're on the right track. You sneeze when an *external* irritant enters your nose. However, the neurotransmitters that send signals to the brain in order to initiate a sneeze are shut down during REM sleep. Also, because of reduced movement, you don't encounter as many particulates in the air. You can sneeze if the irritant is significant enough, but you will wake up to do it (you can test this on your roomy with some cinnamon). On the other hand, coughing during a cold is to expel *internal* mucus from your airway, and is instigated by internal stimuli and those nerves are not suppressed the same way while sleeping.
passages: Sneezing cannot occur during sleep due to REM atonia – a bodily state where motor neurons are not stimulated and reflex signals are not relayed to the brain. Sufficient external stimulants, however, may cause a person to wake from sleep to sneeze, but any sneezing occurring afterwards would take place with a partially awake status at minimum.
  
  Section::::Description.
   Cough may also be caused by conditions affecting the lung tissue such as bronchiectasis, cystic fibrosis, interstitial lung diseases and sarcoidosis. Coughing can also be triggered by benign or malignant lung tumors or mediastinal masses. Through irritation of the nerve, diseases of the external auditory canal (wax, for example) can also cause cough. Cardiovascular diseases associated with cough are heart failure, pulmonary infarction and aortic aneurysm. Nocturnal cough is associated with heart failure, as the heart does not compensate for the increased volume shift to the pulmonary circulation, in turn causing pulmonary edema and resultant cough. Other causes of nocturnal cough include asthma, post-nasal drip and gastroesophageal reflux disease (GERD). Another cause of cough occurring preferentially in supine position is recurrent aspiration.
   While there are many causes of chronic cough, it is generally not essential for an extensive evaluation of multiple causes of cough to be made since the clinical pattern is usually sufficiently apparent that the diagnosis can be made by the clinical presentation, i.e., a repetitive harsh barking cough that is absent once asleep. Those familiar with this disorder readily recognize it without much in the way of testing.
  
  Section::::Treatment.
  
  Successful treatments have involved a few reports utilizing hypnosis, but suggestion therapy has been most extensively used. 
   The coughing episodes are also episodic, progressively severe and eventually nocturnal. They are initiated by a “ticking sensation” deep in the throat or more typically behind the suprasternal notch. This sensation then causes the patient to cough. The cough is therefore a ‘normal’ response to this ticking sensation rather than an uncontrolled muscular contraction of the diaphragm or intercostal muscles. The coughing episodes can be severe with incontinence, vomiting, visual phosphenes (“seeing stars”), and post-tussive headache. These episodes typically progress from mild to severe over the years and eventually will awaken the patient from sleep. In between episodes, the patient is normal and respiratory examination does not reveal reactive airways disease (asthma) or allergies. The coughing episodes can be triggered by loud or prolonged talking, exercise or the choking episodes described above.
   Section::::Symptoms.
  
  Habit cough is characterized by a harsh barking cough, and becomes persistent for weeks to months. The cough's hallmarks are severe frequency, often a cough every 2–3 seconds, and the lack of other symptoms such as fever. The child can have trouble falling asleep but once asleep will not cough. Absence once asleep is considered a essential.
  
  Section::::Diagnosis.
   A cough can be classified by its duration, character, quality, and timing. The duration can be either acute (of sudden onset) if it is present less than three weeks, subacute if it is present between three or eight weeks, and chronic when lasting longer than eight weeks. A cough can be non-productive (dry) or productive (when sputum is coughed up). It may occur only at night (then called "nocturnal cough"), during both night and day, or just during the day.
   Later that night (some contemporary accounts refer to the time as the morning of the following day), a similar incident was also reported by a young mother living close by. She was awakened by the sound of her daughter coughing but found herself unable to leave her bed.
   As the muscle tone of the body ordinarily relaxes during sleep, and the airway at the throat is composed of walls of soft tissue, which can collapse, it is not surprising that breathing can be obstructed during sleep. Although a minor degree of OSA is considered to be within the bounds of normal sleep, and many individuals experience episodes of OSA at some point in life, a small percentage of people have chronic, severe OSA.
   It is recognized with increasing frequency that patients who have both obstructive sleep apnea and asthma often improve tremendously when the sleep apnea is diagnosed and treated. CPAP is not effective in patients with nocturnal asthma only.
  
  Section::::Asthma and gastro-esophageal reflux disease.
  
  If gastro-esophageal reflux disease (GERD) is present, the patient may have repetitive episodes of acid aspiration. GERD may be common in difficult-to-control asthma, but according to one study, treating it does not seem to affect the asthma.
   Some roots cannot be reconstructed with an ablauting , an example being 'to grow, to become'. Such roots can be seen as generalized zero grades of unattested forms like , and thus follow the phonotactical rules.
  
  Some roots like 'to sneeze' or 'to duck' do not appear to follow these rules. This might be due to incomplete understanding of PIE phonotactics or to wrong reconstructions. , for example, might not have existed in PIE at all, if the Indo-European words usually traced back to it are onomatopoeias.
   BULLET::::- Predominence of REM or NREM: The predominence of REM or NREM sleep during which noises occurs varies from patient to patient. For some cases, a REM predominance has been reported whereas it is the opposite for others. Other reports indicated that sounds may occur at any time during sleep.
  
  Section::::Epidemiology.
   Airway resistance increases by about 230% during NREM sleep. Elastic and flow resistive properties of the lung do not change during NREM sleep. The increase in resistance comes primarily from the upper airway in the retroepiglottic region. Tonic activity of the pharyngeal dilator muscles of the upper airway decreases during the NREM sleep, contributing to the increased resistance, which is reflected in increased esophageal pressure swings during sleep. The other ventilatory muscles compensate for the increased resistance, and so the airflow decreases much less than the increase in resistance.
  
  Section::::Normal.:Steady NREM (Non-REM) sleep.:Arterial blood gases.
   The first report of BVVL syndrome in Japanese literature was of a woman that had BVVL and showed improvement after such treatments. The patient was a sixty-year-old woman who had symptoms such as sensorineural deafness, weakness, and atrophy since she was 15 years old. Around the age of 49 the patient was officially diagnosed with BVVL, incubated, and then attached to a respirator to improve her CO2 narcosis. After the treatments, the patient still required respiratory assistance during sleep; however, the patient no longer needed assistance by a respirator during the daytime.
  
  Section::::Prognosis.
   Although kennel cough is considered to be a multifactorial infection, there are two main forms. The first is more mild and is caused by "B. bronchiseptica" and canine parainfluenza virus infections, without complications from canine distemper virus (CDV) or canine adenovirus (CAV). This form occurs most regularly in autumn, and can be distinguished by symptoms such as a retching cough and vomiting. The second form has a more complex combination of causative organisms including CDV and CAV. It typically occurs in dogs that have not been vaccinated and it is not seasonal. Symptoms are more severe than the first form, and may include rhinitis, conjunctivitis, and fever in addition to a hacking cough.
   Histamine plays a role in wakefulness in the brain. An allergic reaction over produces histamine causing wakefulness and inhibiting sleep Sleep problems are common in people with allergic rhinitis. A study from the N.I.H. found that sleep is dramatically impaired by allergic symptoms and that the degree of impairment is related to the severity of those symptoms s Treatment of allergies has also been shown to help sleep apnea.
  
  Section::::Treatment.:Acupuncture.
   The reflex is impaired in the person whose abdominals and respiratory muscles are weak. This problem can be caused by disease condition that lead to muscle weakness or paralysis, by prolonged inactivity, or as outcome of surgery involving these muscles. Bed rest interferes with the expansion of the chest and limits the amount of air that can be taken into the lungs in preparation for coughing, making the cough weak and ineffective. This reflex may also be impaired by damage to the internal branch of the superior laryngeal nerve which relays the afferent branch of the reflex arc. This nerve is most commonly damaged by swallowing a foreign object, such as a chicken bone, resulting in it being lodged in the piriform recess (in the laryngopharynx) or by surgical removal of said object.
   BULLET::::- (voiced by Stephen Stanton) – Sleepy is always tired. In an interview with "Variety", Scott Menville said that Stephen Stanton came up with over fifty different ways to snore.
  
  BULLET::::- (voiced by Scott Menville) – Sneezy has powerful sneezes and has a variety of allergies that causes him to sneeze. In the episode "Welcome to the Neighborhood," he shows off his handkerchief collection.
  
  Section::::Characters.:The Glooms.
   While sleeping, a normal individual is "at rest" as far as cardiovascular workload is concerned. Breathing is regular in a healthy person during sleep, and oxygen levels and carbon dioxide levels in the bloodstream stay fairly constant. Any sudden drop in oxygen or excess of carbon dioxide (even if tiny) strongly stimulates the brain's respiratory centers to breathe.
   BULLET::::- Christopher Darga as Officer Etling
  
  BULLET::::- Robert Joseph as Officer
  
  BULLET::::- Larry Clarke as Officer Knachez
  
  BULLET::::- Joe Nunez as Mr. Mather
  
  BULLET::::- Vanessa Lee Evigan as Kelly
  
  BULLET::::- Bunny Levine as Rachel
  
  Section::::Production notes.
   Upper airway resistance syndrome is caused when the upper airway narrows without closing. Consequently, airflow is either reduced or compensated for through an increase in inspiratory efforts. This increased activity in inspiratory muscles leads to the arousals during sleep which patients may or may not be aware of.
   Catathrenia has been defined as a parasomnia in the International Classification of Sleep Disorders Diagnostic and Coding Manual (ICSD-2), but there is debate about its classification. Importantly, in the latest version of the International Classification of Sleep Disorders (ICSD-3), catathrenia has been included in the category of respiratory disorders, and thus it has been removed from the parasomnia category, as it was in the second version of the manual; nevertheless, a debate about the nature and classification of the disorder, still exist.
  
  Section::::Signs and symptoms.
   In the United States a sleep disorder specialist can be a Registered Respiratory Therapist with the sleep disorder specialist certification (RRT-SDS) whom performs sleep disorders testing and therapeutic intervention along with diagnosis of sleep related disease such as Obstructive Sleep Apnea or Central Apnea. In Canada it is often an RT with additional training to become a Registered Polysomnography Technician (RPSGT)
  
  Section::::Specialist Respiratory Therapists.:Case management.
   Six things are a good sign for a sick person, namely, sneezing, perspiration, open bowels, seminal emission, sleep and a dream. Sneezing, as it is written: His sneezings flash forth light. Perspiration, as it is written, In the sweat of thy face shalt thou eat bread. Open bowels, as it is written: If lie that is bent down hasteneth to be loosed, he shall not go down dying to the pit. Seminal emission, as it is written: Seeing seed, he will prolong his days. Sleep, as it is written: I should have slept, then should I have been at rest. A dream, as it is written: Thou didst cause me to dream and make me to live.
   Viral and bacterial causes of canine cough are spread through airborne droplets produced by sneezing and coughing. These agents also spread through contact with contaminated surfaces. Symptoms begin after a several day incubation period post-exposure, and in most cases will clear up on their own. However, in young puppies or immunocompromised animals, mixed or secondary infections can progress to lower respiratory infections such as pneumonia.
  
  Section::::Symptoms.
   Section::::Physiology.:Circulation, respiration, and thermoregulation.
  
  Generally speaking, the body suspends homeostasis during paradoxical sleep. Heart rate, cardiac pressure, cardiac output, arterial pressure, and breathing rate quickly become irregular when the body moves into REM sleep. In general, respiratory reflexes such as response to hypoxia diminish. Overall, the brain exerts less control over breathing; electrical stimulation of respiration-linked brain areas does not influence the lungs, as it does during non-REM sleep and in waking. The fluctuations of heart rate and arterial pressure tend to coincide with PGO waves and rapid eye movements, twitches, or sudden changes in breathing.
  