In those cases, the spread between the bid & ask goes to the market maker as compensation for making a market in a stock. For a liquid stock that is easy for the market maker to turn around and buy/sell to somebody else, the spread is small (narrow).
In cerebral hypoxia, sometimes only the oxygen supply is interrupted. Brain cells are extremely sensitive to a lack of oxygen. Some brain cells start dying less than 5 minutes after their oxygen supply disappears. As a result, brain hypoxia can rapidly cause severe brain damage or death.
If the hypoxia was localized to a specific part of the brain, it is likely that any brain damage will also occur only in that region. In this case, long-term effects will depend on the function of that portion of the brain. Damage to left side of the brain may cause the victim to have difficulty with speech and language, while damage to the right side may interfere with visual interpretation or emotional disturbance. Delayed effects. Certain kinds of severe hypoxia may take time to fully show the extent of damage. Some poisoning victims, for example, may show physical and mental impairments several weeks after the initial episode of hypoxia. Coma. If the brain is significantly damaged by oxygen loss, the brain may go into a comatose state to heal and regenerate. However, the longer a coma continues, the greater the likelihood that the person will not recover from a vegetative state--and even if the patient wakes up from a prolonged coma, brain damage is likely to significantly affect his quality of life.