Choking game

The choking game, also known by large number of other names, is not technically a game but a schoolyard activity involving the inducement of unconsciousness or near unconsciousness by restriction of the supply of oxygen to the brain. The highly dangerous activity is traditional and world-wide, passed down for generations in schoolyards, summer camps and neighborhoods. Practitioner demographics are strongly weighted towards juvenile males but includes females and adults of both genders. The activity has been responsible for a large number of juvenile deaths and permanent neurological disabilities almost entirely among the juvenile male cohort. The attractions are manifold: it is done as a dare, it can induce a brief sense of euphoria, it is reported to enhance erotic feelings, it is amusing to some to watch others losing consciousness or behaving erratically, the prospect of an altered state of consciousness, the experience of a brownout or, more recently, copycatting elements of the film Flatliners. It is also free, legal and appears innocuous to those without a proper understanding of the mechanism involved.

How the choking game works

There are actually two distinct methods involved. Both result in unconsciousness by depriving the brain of oxygen but each has a very different mechanism. The two tend to get confused or treated as one. The two mechanisms are strangulation and self-induced hypocapnia and work as follows:

The vulnerable carotid artery, (large, red tube), and the vagus nerve running parallel on its left

1. Strangulation restricts the blood flow to the brain by compressing the carotid artery in the neck. This is achieved either by pressing the thumbs against the arteries on both sides of the neck simultaneously or the use of a ligature. Apart from the direct restriction of blood to the brain there are two other significant physiological responses to pressing on the neck:

• Pressing on the carotid arteries also presses on baroreceptors known as the carotid sinus bodies. These bodies then cause vasodilation in the brain leading to insufficient blood to perfuse the brain with oxygen and maintain consciousness.
• A message is also sent via the vagus nerve to the main pacemaker of the heart to decrease the rate and volume of the heartbeat, typically by up to a third. [1] In some cases there is evidence that this may escalate into asystole, a form of cardiac arrest that is difficult to treat. The vulnerability of the victim and speed of onset is unpredictable and not properly understood. There is a dissenting view on the full extent of this but it is agreed that pressure on the vagus nerve causes changes to pulse rate and blood pressure and is dangerous in cases of carotid sinus hypersensitivity.

The use of thumbs on the neck can be self-induced and usually stops automatically on blackout. Where an assistant applies hand pressure, and in all cases where a ligature is used, stopping at the right moment before permanent damage occurs becomes a judgement on the part of the operator or just good luck. Self-strangulation through the use of a ligature is the most common cause of death or brain damage although many schoolchildren have accidentally killed or caused permanent brain damage to their friends by all methods. It is believed that many deaths attributed to suicide by adolescents are actually solo self-asphyxiations and death was an unintended outcome.

2. Self-induced hypocapnia. This involves no compression of the neck but requires hyperventilation for a minute, or until symptoms of hypocapnia such as tingling, light-headedness or dizziness are felt, followed by a breath-hold. The effect is greatly enhanced if lung air pressure is increased by holding the breath 'hard', that is forcing exhalation while allowing no air to escape. This alone is enough to cause a blackout but usually tradition requires one of a number of other actions such as a bear hug given from behind or pressure applied by another person under or over the heart. The fact that hyperventilation causes rapid cerebral hypoxia is paradoxical because the body should be well stocked with oxygen after overbreathing. The mechanism here is that the blood is made abnormally alkaline as a result of the excessive elimination of the CO₂ that keeps it acidic; this rise in blood pH is termed alkalosis. The symptoms of alkalosis are: neuromuscular irritability, muscular spasms, tingling and numbness of the extremities and around the mouth, and a dizziness, or giddiness, often interpreted as a sense of euphoria. This brief euphoria is what practitioners of the fainting game seek. Unfortunately alkalosis has other far reaching and very complex effects on the neuromuscular system and among other things it interferes with normal oxygen utilization by the brain. In the body alkalosis generally induces vasodilatation but in the brain alone it causes vasoconstriction. This vasoconstriction appears to be exacerbated by a sudden increase in blood pressure caused by squeezing or holding the breath ‘hard’. The alkalosis induced euphoria can be followed rapidly by hypoxia induced unconsciousness. The sequence of events leading to unconsciousness from hyperventilation are as follows:

1. Decrease in partial pressure of alveolar CO₂.
2. Decrease in partial pressure of arterial CO₂.
3. Increase in blood pH, (respiratory alkalosis).
4. Vasoconstriction of blood vessels supplying brain.
5. Pooling of the blood present in the brain at the time.
6. Brain rapidly uses up O₂ available in the pooled blood.
7. O₂ concentration in the brain drops.
8. Unconsciousness from hypoxia of cerebral tissue.

Because the brain maintains no reserves of O₂ and, unlike other organs, has an exceedingly low tolerance of O₂ deprivation it is highly vulnerable if vasoconstriction is not reversed. Normally, if the brain is hypoxic, autonomous systems in the body divert blood to the brain at the expense of other organs; because the brain is vasoconstricted this mechanism is not available. Vasoconstriction is only reversed by the build-up of CO₂ in the blood through suspension of breathing. If this build-up does not happen quickly enough, or if the vasodilation mechanism itself is slow to respond, irreversible brain damage or death becomes a possibility. This mechanism is too complex to be dealt with adequately within this article; for a good treatment of the paradoxical relationship between hyperventilation and hypoxia see USAF Respiratory Physiology.

In some traditional versions the bear hug is replaced by pressure on the neck, in which case blackout is a hybrid of strangulation and self-induced hypocapnia.

Other mechanisms. Unconsciousness may be induced by other methods: Pressure over the carotid sinus may induce a syncope (fainting) without any other action at all but this is difficult to reproduce and is not the basis of the game. For those people susceptible to carotid sinus syncope, and most people would be unaware until it occurs, this can be an exceedingly dangerous game.

In both strangulation and self-induced hypocapnia blackouts the victim may experience dreaming or hallucinations, though fleetingly, and regains consciousness with involuntary movement of their hands or feet much to the amusement of the onlookers. Full recovery is usually made within seconds but these activities cause many deaths and invalidities every year, particularly when played alone or with a ligature. Permanent brain damage may not be immediately apparent.

Other names

The practice goes by many other names in different parts of the world or simultaneously in a single location. Common names in the United Kingdom, Australia and North America include:

The Fainting Game, Airplaning, America Dream Game, Black Out Game, Breath Play, California Choke, California Dreaming, California High, California Knockout, Choke Out, Dieing game, Dream Game, Dreaming Game, Elevator, Flatline Game, Flat Liner, Flatliner Game, Funky Chicken, Harvey Wallbanger, Hyperventilation Game, Knockout Game, Pass-out Game, Passing Out Game, Natural High, Sleeper Hold, Space Cowboy, Space Monkey, Suffocation Game, Suffocation Roulette, Teen Choking Game, Rising Sun, High Riser, Risers, Tingling Game, Trip to Heaven, a Rocket Ride, The Game and Speed Dreaming.

See also

• Asphyxiation
• Erotic asphyxiation
• Strangling
• Shallow water blackout for an account of other blackout dangers of self-induced hypocapnia.

External links

• Choking Game Information
• Deadly Games Children Play
• USAF Respiratory Physiology
• Breath Control Play
• carotid sinus hypersensitivity
• Issaquah High School "Teen Choking Game"

Victims' webpages

• Dylan Blake
• Braden Erickson
• Jesse Grant
• Gabriel Mordecai
• Nick Serna
• Kimber Wilson
• Daniel Sheppard