Just a 10 percent shift in the salt concentration of your blood would make you very sick. To keep that from happening, the body has developed a finely tuned physiological circuit that includes information about that and a beverage's saltiness, to know when to signal thirst.
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Given supportive, nurturing conditions, highly reactive "orchid" children can thrive when tackling challenges, pediatrician and author Thomas Boyce says, especially if they have the comfort of a regular routine.
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Person undergoing a CAT scan in hospital with PET scan equipment. Emerging studies report findings of brain deterioration in females to be slower than that of males'.
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A scanning electron micrograph shows microglial cells (yellow) ingesting branched oligodendrocyte cells (purple), a process thought to occur in multiple sclerosis. Oligodendrocytes form insulating myelin sheaths around nerve axons in the central nervous system.
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Researchers say human brains can become overwhelmed by cute traits, such as large eyes and small noses, embodied by movie characters like Bambi.
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Before light reaches these rods and cones in the retina, it passes through some specialized cells that send signals to brain areas that affect whether you feel happy or sad.
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Patients awaiting epilepsy surgery agreed to keep a running log of their mood while researchers used tiny wires to monitor electrical activity in their brains. The combination revealed a circuit for sadness.
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The fix was in for this rhesus macaque drinking juice on the Ganges River in Rishikesh, Uttarakhand, India. No gambling was required to get the reward.
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Several circular herpes virus particles are seen near a cell membrane. Roseola herpes virus causes a childhood illness marked by skin rashes and now has been found in brains with Alzheimer's disease.
Marines based in Okinawa, Japan, fire an M136 AT-4 rocket launcher as part of a weapons training exercise on the Kaneohe Bay Range Training Facility, in 2014.
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