question: Is there a scientific reason for people to clench up when someone tries to touch their neck? I know not everyone is like that but for me even though I know I'm not going to get hurt my body immediately reacts anyways haha
comment: Your neck is very vulnerable, even if you know you aren't going to get hurt, your subconscious still reacts instinctively and tries to protect your neck.
passages: Injury in this nerve causes paralysis (as always) to the muscles innervated by it, most importantly deltoid muscle. This muscle is the main abductor of the shoulder joint from 18 to 90 degrees (from 0 to 18 by supraspinatus). Injury can result in a reduction in shoulder abduction. So a test can be applied to a patient with injury of axillary nerve by trying to abduct the injured shoulder against resistance.
   To assess the strength of the trapezius muscle, the examiner asks the patient to shrug his or her shoulders against resistance. In patients with damage to the spinal accessory nerve, shoulder elevation will be diminished, and the patient will be incapable of raising the shoulders against the examiner's resistance.
  
  Section::::Treatment.
   The fencing response is a peculiar position of the arms following a concussion. Immediately after moderate forces have been applied to the brainstem, the forearms are held flexed or extended (typically into the air) for a period lasting up to several seconds after the impact. The fencing response is often observed during athletic competition involving contact, such as American football, hockey, rugby union, rugby league, Australian rules football and combat sports. It is used as an overt indicator of injury force magnitude and midbrain localization to aid in injury identification and classification for events including on-field and/or bystander observations of sports-related head injuries.
   This reflex is observed in patients with upper motor neuron lesions. It was frequently attributed to the action of the golgi tendon organ, likely because of early studies showing that tendon organs are activated by strong muscle stretch and inhibit motoroneurons of the stretched muscle. It was thought that this was a protective reflex, preventing application of so much force that muscles become damaged. More recent work strongly suggests that tendon organs are not involved in the clasp knife reflex, but that other sensory receptors in muscles are responsible.
  
  Section::::Example.
   Most patients who find themselves restrained naturally think they can free themselves by pulling hard at the restraints. But the restraints are made out of plastic mesh, which cannot be broken by being pulled with human strength. Other patients attempt to unfasten the restraints around the wrist, but find they cannot reach the fastener unless they have abnormally flexible joints. Some do manage to slip their hands through the cuff, though competent workers prevent this from happening.
   Section::::Symmetrical tonic neck reflex.
   Section::::Neck crank.:Standing frontal facelock.
  
  Facing opponent as though leveraging a guillotine, however cross facing the individual and rotating their head laterally, creating an incredibly dangerous hyperflexion of the neck sideways when hips are leveraged and the cross face is pulled up, attempting to apply extreme pressure and damage to the cervical vertebrae.
  
  Section::::Spine crank.
   Injury to this nerve is usually apparent on inspection when the scapula on the injured side is located farther from the midline than the uninjured scapula. The patient would be unable to pull their shoulder back, as when standing at attention. Isolated dorsal scapular nerve injury is uncommon, but case reports usually involve injury to the scalene muscles.
   The cattle catch (also referred to as reverse crucifix, iron cross or stocks) is a hyperflexing neck crank involving trapping the opponent's hands and forcing the head towards his or her chest. The technique is performed with the opponent lying on his or her back, and the combatant performing the neck crank perpendicularly face-down in a side mount position above the head of the opponent, with the opponent's head resting towards his armpit. The combatant traps one arm using the legs, and the other using the arms. By using the pinned arms and legs as a point of leverage, the combatant can forcefully crank the head towards the opponent's chest.
   There are multiple techniques used in the diagnosis of spondylosis, these are;
  
  BULLET::::- Cervical Compression Test, a variant of Spurling's test, is performed by laterally flexing the patient's head and placing downward pressure on it. Neck or shoulder pain on the ipsilateral side (i.e. the side to which the head is flexed) indicates a positive result for this test. A positive test result is not necessarily a positive result for spondylosis and as such additional testing is required.
  
  BULLET::::- Lhermitte sign: feeling of electrical shock with patient neck flexion
   Section::::Neck crank.:Crucifix neck crank.
  
  The crucifix neck crank is similar to the cattle catch, but involves the combatant performing the neck crank being mounted on the opponent. Both of the opponent's arms are controlled, and the opponent's head is held in the armpit. By cranking the body upwards while keeping a tight hold on the opponents arms, the opponents head is forced towards his or her chest.
  
  Both the cattle catch and the crucifix neck crank are colloquially referred to simply as the crucifix, which often leads to confusion with the traditional crucifix position.
  
  Section::::Neck crank.:Twister.
   Strength testing is similar to range of motion testing, except that the patient performs the actions against the examiner's resistance. The examiner measures sternocleidomastoid muscle function by asking the patient to turn his or her head against resistance. Simultaneously, the examiner observes the action of the contralateral sternocleidomastoid muscle. For example, if the patient turns his or her head to the right, the left sternocleidomastoid muscle normally will tighten.
   Disorders of the neck are a common source of pain. The neck has a great deal of functionality but is also subject to a lot of stress. Common sources of neck pain (and related pain syndromes, such as pain that radiates down the arm) include (and are strictly limited to):
  
  BULLET::::- Whiplash, strained a muscle or another soft tissue injury
  
  BULLET::::- Cervical herniated disc
  
  BULLET::::- Cervical spinal stenosis
  
  BULLET::::- Osteoarthritis
  
  BULLET::::- Vascular sources of pain, like arterial dissections or internal jugular vein thrombosis
  
  BULLET::::- Cervical adenitis
  
  Section::::Other animals.
   Neurapraxia is most commonly observed in athletes involved in collision sports, such as American football. Athletes participating in collision sports most often suffer from cervical cord neurapraxia, also known as transient neurapraxia. Cervical cord neurapraxia is the result of a severe collision in which a blow to the crown of the athlete’s head forcefully extends or compresses the neck. Numbness, stinging, and/or weakness in the arms, legs or both, distinguish cervical cord neurapraxia. Typical episodes of transient nuerapraxia only last a few seconds and symptoms dissipate entirely. Though the severity of the injury can range, transient neurapraxia does not lead to permanent paralysis of the affected muscles. Subsequent spinal cord injury after an episode of cervical cord neurapraxia has not been observed. However, athletes who experience an episode of transient cervical neurapraxia face an approximately 50% chance of a repeat episode if they continue to participate in collision sports.
   Based in part on advice from the security forces of Israel and Sri Lanka—two countries with experience of suicide bombings—Operation Kratos guidelines allegedly state that the head or lower limbs should be aimed at when a suspected suicide bomber appears to have no intention of surrendering. This is contrary to the usual practice of aiming at the torso, which presents the biggest target. A successful hit to the torso may detonate an explosive belt.
   The symmetric tonic neck reflex normally appears and develops around 6–9 months of age and should integrate by around 12 months. When the child's head flexes forward, extending the back of the neck, the upper extremities will contract and the lower extremities will extend. Conversely, when the child's head is extended backward, contracting the back of the neck, the upper extremities will extend and the lower extremities will contract. This reflex is important to help a child push up onto their hands and knees, but may inhibit actual forward creeping or crawling if it is not properly integrated. If this reflex is retained beyond 2–3 years, it may result, directly or indirectly, in a range of physical and neurological developmental delays.
   ""I was wearing the suit and tie shit back then on some old time gangster shit. He had that other shit like, ‘˜Girl come do me.’ I guess they wasn’t feeling that shit so they chose to push me harder than they pushed him. That ain’t my fault what the fuck are you mad at me for? So you know how that shit is. He ain’t gonna come to my face and say nothing so later on he put that shit in his little rhyme or whatever throwing a subliminal jab. That shit is neither here nor there"."
   Strength testing of these muscles can be measured during a neurological examination to assess function of the spinal accessory nerve. Poor strength or limited movement are suggestive of damage, which can result from a variety of causes. Injury to the spinal accessory nerve is most commonly caused by medical procedures that involve the head and neck. Injury can cause wasting of the shoulder muscles, winging of the scapula, and weakness of shoulder abduction and external rotation.
  
  The accessory nerve is derived from the basal plate of the embryonic spinal segments C1–C6.
  
  Section::::Structure.
   Injury to the brachial plexus may affect sensation or movement of different parts of the arm. Injury can be caused by the shoulder being pushed down and the head being pulled up, which stretches or tears the nerves. Injuries associated with malpositioning commonly affect the brachial plexus nerves, rather than other peripheral nerve groups. Due to the brachial plexus nerves being very sensitive to position, there are very limited ways of preventing such injuries. The most common victims of brachial plexus injuries consist of victims of motor vehicle accidents and newborns.
   Psychologists at NUI Galway and University College Dublin have recently begun to measure body-centred countertransference in female trauma therapists using their recently developed "Egan and Carr Body Centred Countertransference Scale", a sixteen symptom measure. High levels of body-centred countertransference have since been found in both Irish female trauma therapists and clinical psychologists. This phenomenon is also known as "somatic countertransference" or "embodied countertransference" and links to mirror neurons and automatic somatic empathy for others due to the actions of these neurons have been hypothesised.
  
  Section::::Bibliography.
   A section of skin innervated through a specific part of the spine is called a dermatome, and injury to that part of the spine can cause pain, numbness, or a loss of sensation in the related areas. Paraesthesia, a tingling or burning sensation in affected areas of the skin, is another symptom. A person with a lowered level of consciousness may show a response to a painful stimulus above a certain point but not below it. 
   Ankle of the patient is relaxed. It is helpful to support the ball of the foot at least somewhat to put some tension in the Achilles tendon, but don’t completely dorsiflex the ankle. A small strike is given on the Achilles tendon using a rubber hammer to elicit the response. If the practitioner is not able to elicit a response, a Jendrassik maneuver can be tried by having the patient cup their fingers on each hand and try to pull the hands apart. A positive response is marked by a brisk plantarflexion of the foot. The response is also graded into Grade 0-4 according to the reflex grading system.
   Section::::Relationship to fencing reflex and posturing.
  
  The fencing response designation arises from the similarity to the asymmetrical tonic neck reflex in infants. Like the reflex, a positive fencing response resembles the "en garde" position that initiates a fencing bout, with the extension of one arm and the flexion of the other.
   A study by Chung et al. (2006) focused on how the responses of spinal cord injury post-traumatic stress varied depending on age. The researchers tested different age groups including young adults, middle-aged, and elderly; the average age was 25, 48 and 65 for each group respectively. After the study, they concluded that age does not make a difference on how spinal cord injury patients respond to the traumatic events that happened. However, they did mention that age did play a role in the extent to which the external locus of control was used, and concluded that the young adult group demonstrated more external locus of control characteristics than the other age groups to which they were being compared.
   BULLET::::- In the Beastie Boys song "Intergalactic", the lyrics state, "If you try to knock me you'll get mocked/I'll stir fry you in my wok/Your knees'll start shakin' and your fingers pop/Like a pinch on the neck of Mr. Spock".
  
  Section::::Death grip.
  