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SIGHT

STRENGTH

SENSATION

BRAIN POWER

STRENGTH

How can adrenaline help you lift a 3,500-pound car?

In 2006 in Tucson, Ariz., Tim Boyle watched as a car hit 18-year-old Kyle Holtrust. The car pinned Holtrust, still alive, underneath. Boyle ran to the scene of the accident and lifted the Camaro off the teenager while the driver of the car pulled him to safety. What accounts for feats of superhuman strength such as this one? Are they glimpses into the lives of superheroes' alter egos? Or are all of us imbued with amazing strength?

Although well-documented when they do occur, feats of hysterical strength -- unnatural and amazing strength tapped during high-stress situations -- are not recognized by medical science. This is largely due to the problem of gathering evidence: Instances like these come about without warning, and to reproduce these situations in a clinical setting would be unethical and dangerous.

But we are aware of the effects of adrenaline, a hormone shown to increase strength to amazing degrees for short periods of time. Read More at HowStuffWorks...

How Pain Works

What happens when you're cutting a bagel and slice your hand with the knife? You'll probably feel an immediate sharp pain, followed by a longer-lasting dull ache. Eventually, both sensations will go away. But how? And what exactly is pain?

Pain is the most common reason people seek medical attention, but is also hard to define because it's a subjective sensation. The International Association for the Study of Pain defines it as an "unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage."

Obviously, this definition is pretty vague. One physician even remarked that pain is whatever the patient says it is. So let's just say that pain is a warning sensation to your brain that some type of stimulus is causing or may cause damage, and you should probably do something about it.

Pain perception, or nociception (from the Latin word for "hurt"), is the process by which a painful stimulus is relayed from the site of stimulation to the central nervous system. Nociception requires several components:

• Stimulus -- Pressure, punctures and cuts (mechanical) or burns (heat or chemical) act as a stimulus
• Reception -- A nerve ending senses the stimulus
• Transmission -- A nerve sends the signal to the central nervous system. The relay of information usually involves several neurons within the central nervous system.
• Pain center(s) -- Areas of the brain receive the information for further processing or action.

Read More at HowStuffWorks...

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