10- Pam Reynolds' Experienced Life After Death

The human brain can do some amazing things - and humans can do amazing things because of it. Just to name one example, we can accept light along the visible wavelength reflected from objects in our environment into our eyes. Our optic nerves convert that light into electrochemical impulses, which is the language the brain uses to communicate. As this electricity passes along a neural network, it reaches the hippocampus, the region of the brain responsible for analyzing and categorizing these impulses.

These categories determine which region of the brain receives the impulses routed by the hippocampus. So, an impulse sent to the visual cortex suddenly becomes a large green metal road sign that we understand as our exit. We veer the car off the highway and continue on toward the grocery store happy as a lark.

Even the most mundane operations of our brains are pretty amazing. Those feats, however, are nothing compared to some of the things that a small handful of people's brains have done. What follows, in no particular order, is a tidy list of some of the most amazing -- and horrible -- things that people's brains have ever done.

Pam Reynolds' brain managed to capture the sights and sounds of the operating room, despite her being clinically dead.

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By all accounts, Pam Reynolds, a blues singer from Atlanta, Ga., was a normal person before she underwent surgery for a brain aneurysm. During the procedure, physicians drained all of the blood from Reynolds' brain, rendering it completely inactive for 45 minutes. All normal brain operations -- from accepting signals from the stomach that the sensation of hunger should cease or the transmission of aural and visual information -- ceased.

Yet, upon awakening, physicians found Reynolds could describe the procedure in incredible detail. She's considered one of the most solid examples of a near-death experience(NDE) on record. Reynolds' experience is far from unique; one study of cardiac patients in a single hospital in the Netherlands found that of the 344 patients who'd been declared clinically dead, 18 percent reported having some experience of life after death [source: van Lommel].

What's most impressive about Reynolds' NDE is that her brain was brought to a nonfunctioning state by an experienced medical staff. Yet, she was still capable somehow of relating information like the type of bone saw her physicians used to cut off her skull and conversation between the operating staff [source: Sabom].

9- Henry Molaison's Couldn't Form New Memories

Following brain surgery to remove his temporal medial lobe, Henry Molaison suffered anterograde amnesia.

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Henry Molaison was a one-of-a-kind brain patient. He was literally the only person to have ever undergone a radical procedure that removed the medial temporal lobe to treat debilitating seizures. When his physician found what had become of his patient's memory, the doctor refused to carry out the procedure on anyone else and successfully lobbied against its use by other physicians.

What happened? The removal of Molaison's medial temporal lobes, located above the ears, left him with the rare disorder of complete anterograde amnesia. As a result of this condition, Molaison was completely unable to form any new memories. Molaison could retain old memories and remember the ones he'd formed throughout his life up until the surgery that took place in his 20s. He was also capable of forming procedural memories, or habits. However, he couldn't form new declarative memories, or remember who his friends were, what he'd had for lunch or who was president. He lived this way for 55 years, dying in 2008 at age 82 [source: Carey].

Because of his unique condition, Molaison served as the subject of a number of studies, becoming widely known in the neurological community as patient "H.M."

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