Pavlov’s Neurons: Brain Cells That Are A Key To Learning Discovered

More than a century after Ivan Pavlov’s dog was conditioned to salivate when it heard the sound of a tone prior to receiving food, scientists have found neurons that are critical to how people and animals learn from experience.

Using a new imaging technique called Arc catFISH, researchers from the University of Washington have visualized individual neurons in the amygdalas of rat brains that are activated when the animals are given an associative learning task.

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When a light goes on during thought processes

Thought processes made visible: An international team of scientists headed by Mazahir Hasan of the Max Planck Institute for Medical Research in Heidelberg has succeeded in optically detecting individual action potentials in the brains of living animals.

The scientists introduced fluorescent indicator proteins into the brain cells of mice via viral gene vectors: the illumination of the fluorescent proteins indicates both when and which neurons are communicating with each other. This new method enables the observation of brain activity over a period of many months and provides new ways of identifying, for example, the early onset of dysfunction in neurological disorders such as Alzheimer’s and Parkinson’s. The fluorescent proteins could also provide scientists with information about the ways in which normal aging processes affect nerve cell communication (Nature Methods, September 2008).

How memories are made, and recalled

What makes a memory? Single cells in the brain, for one thing. For the first time, scientists at UCLA and the Weizmann Institute of Science in Israel have recorded individual brain cells in the act of calling up a memory, thus revealing where in the brain a specific memory is stored, and how it is able to recreate it.

Reporting in the current edition of the journal Science, Dr. Itzhak Fried, senior author and a UCLA professor of neurosurgery, and colleagues, recorded the activity of hundreds of individual neurons making memories from the brains of 13 epilepsy patients being treated at the UCLA Medical Center. The patients’ surgeons had placed electrodes into their brains to locate the origin of their seizures before surgical treatment (standard procedure in such cases).

Learning Suffers If Brain Transcript Isn’t Transported Far Out To End Of Neurons

Neuroscientists at Georgetown University Medical Center have solved a mystery that lies at the heart of human learning, and they say the solution may help explain some forms of mental retardation as well as provide clues to overall brain functioning.

Trigger For Brain Plasticity Identified

Researchers have long sought a factor that can trigger the brain’s ability to learn – and perhaps recapture the “sponge-like” quality of childhood. In the August 8 issue of the journal Cell, neuroscientists at Children’s Hospital Boston report that they’ve identified such a factor, a protein called Otx 2.

Otx2 helps a key type of cell in the cortex to mature, initiating a critical period — a window of heightened brain plasticity, when the brain can readily make new connections.

Killer carbs: scientist finds the key to overeating as we age

A Monash University scientist has discovered key appetite control cells in the human brain degenerate over time, causing increased hunger and potentially weight-gain as we grow older.

Coatings to help medical implants connect with neurons

Plastic coatings could someday help neural implants treat conditions as diverse as Parkinson’s disease and macular degeneration.

The coatings encourage neurons in the body to grow and connect with the electrodes that provide treatment.

Brain’s reaction to self-administered cocaine differs

New research has uncovered a fundamental cellular mechanism that may drive pathological drug-seeking behavior. The study, published by Cell Press in the July 31 issue of the journal Neuron, examines the brain’s reward circuitry and details strikingly distinct influences of self-administered cocaine compared to natural rewards or passive cocaine injection.

When neurons fire up: Study sheds light on rhythms of the brain

In our brains, groups of neurons fire up simultaneously for just milliseconds at a time, in random rhythms, similar to twinkling lightning bugs in our backyards. New research from neuroscientists at Indiana University and the University of Montreal provides a model — a rhyme and reason — for this random synchronization.