Category: Cognition (page 1 of 3)

2014 nobel prizes

Nobel_medal

The Nobel prizes were awarded this week. Each year there are three science related awards in the fields of medicine, physics and chemistry.

In the field of medicine, the award went to John O´Keefe, May-Britt Moser and Edvard I. Moser for discovering the brain cells that make up our positioning system. In 1971 John O’Keefe discovered that when a rat was in a certain part of the room, one part of the hippocampus was always activated. When the rat was in other parts of a room there were different cells activated. He termed these cells “place cells” and determined that they formed a map. In 2005, the Mosers discovered what they called “grid cells”. These cells generated a coordinate system and aid in finding our way along paths. Read more about the physiology and medicine prize here.

This years physics medal went to the invention of LEDs and was awarded to Isamu Akasaki, Hiroshi Amano, and Shuji Nakamura. The three researchers contributed to the development of LED technology, which is prevalent in today’s telephones, lamps, and computers. LED lights emit brighter light than incandescent lights and for longer periods of time. Read more about the award at Scientific American. The press release is here.

The chemistry prize was awarded to Eric Betzig, Stefan Hell, and William Moerner for developing super resolved fluorescence microscopy. Researchers thought they were limited by the limit of diffraction when it came to resolving images under a microscope. The three Nobel recipients have developed technology that helped overcome this limitation and resolve images into the nanometer scale. Stefan Hell developed a technique called stimulated emission depletion microscopy or STED. Bezig and Moerner, working separately, performed the groundwork for the development of single molecule microscopy. You can read the press release here, and a more detailed description of high resolution microscopy here.

dopamine explained

 

Dopamine

The structure of dopamine

Last week on Slate, Bethany Brookshire explains the neurotransmitter dopamine and how it effects many different chemical processes:

What is dopamine? Dopamine is one of the chemical signals that pass information from one neuron to the next in the tiny spaces between them. When it is released from the first neuron, it floats into the space (the synapse) between the two neurons, and it bumps against receptors for it on the other side that then send a signal down the receiving neuron. That sounds very simple, but when you scale it up from a single pair of neurons to the vast networks in your brain, it quickly becomes complex. The effects of dopamine release depend on where it’s coming from, where the receiving neurons are going and what type of neurons they are, what receptors are binding the dopamine (there are five known types), and what role both the releasing and receiving neurons are playing.

It has far more roles in the brain to play. For example, dopamine plays a big role in starting movement, and the destruction of dopamine neurons in an area of the brain called the substantia nigra is what produces the symptoms of Parkinson’s disease. Dopamine also plays an important role as a hormone, inhibiting prolactin to stop the release of breast milk. Back in the mesolimbic pathway, dopamine can play a role in psychosis, and many antipsychotics for treatment of schizophrenia target dopamine. Dopamine is involved in the frontal cortex in executive functions like attention. In the rest of the body, dopamine is involved in nausea, in kidney function, and in heart function.

does thinking wear you out?

The Thinker

Maybe. Maybe not.

From Popular Science:

That said, studies show that people do slow down after performing taxing mental tasks. One experiment, conducted by Samuele Marcora of the University of Kent, split subjects into two groups. Members of the first played a mentally challenging computer game. Those in the second group watched a documentary about trains or sports cars. Then everyone took an endurance test on an exercise bike. Marcora found that people who were “mentally exhausted” gave up pedaling more quickly than the documentary-watching controls. It was as if the heavy thinking had worn them out.

At the same time, Marcora found no correlation between the mental task and measures of their cardiovascular response, such as blood pressure, oxygen consumption, or cardiac output. In other words, the mental workout didn’t seem to slow their bodies so much as it appeared to skew their perception of how hard a given physical task might be.

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