Nicotine administration in humans is known to sharpen attention and to slightly enhance memory. Now scientists, using functional magnetic resonance imaging (MRI), have identified those areas of the brain where nicotine exerts its effects on cognitive skills.
Their findings suggest that nicotine improves attention in smokers by enhancing activation in the posterior cortical and subcortical regions of the brain--areas traditionally associated with visual attention, arousal, and motor activation. This study provides the first evidence that nicotine-induced enhancement of parietal cortex activation is associated with improved attention.
Nicotine may improve the symptoms of depression in people who do not smoke, Duke University Medical Center scientists have discovered.
New research suggests that nicotine treatment protects against the same type of brain damage that occurs in Parkinson's disease. The research was conducted in laboratory animals treated with MPTP, an agent that produces a gradual loss of brain function characteristic of Parkinson's. Experimental animals receiving chronic administration of nicotine over a period of six months had 25 percent less damage from the MPTP treatment than those not receiving nicotine.
Nicotine is a widely seen drug found in tobacco products. It is usually associated with the negative effects of smoking, including the addiction and cravings. However, nicotine can be helpful for people with pathological disease states such as Alzheimer's disease, Parkinson's disease, attention deficit/hyperactivity disorder and schizophrenia. A recent study done here at UVM investigated the cognitive improvements of three groups: smokers, normal volunteers, and contrasts those with trials of nicotinic stimulation in pathological disease states. Chemical receptors for nicotine are found all throughout the central nervous system, and stimulating parts of the brain with nicotinic acid have shown to be vital to memory function. Nicotinic acid is a B vitamin found in yeast, liver, eggs, and other foods and is also known as niacin, or vitamin B3.
Tue, 21 Aug 2007 10:48 UTC
Researchers have long been aware that fewer smokers get Alzheimer's and Parkinson's diseases than non-smokers. Up to April l992, of the 17 studies on Alzheimer's and smoking which had been published in peer-reviewed journals, 13 reported a reduced risk for smokers and only four found no difference between smokers and non-smokers. Similar findings have been published on the effect of smoking and Parkinson's disease.
A Mosquito which can carry a host of deadly diseases has entered Britain.
Two Asian tiger mosquitoes, which can transmit up to 23 infections - including West Nile virus and dengue fever - were found in a suburban back garden.
The last thing you want to wear into Dr. Robert Bibb's dermatology office is a dark tan and a milk mustache.
"A tan is the body's response to damage," said Bibb, who suspected that ultraviolet A rays were more than innocent bystanders to sun damage years before it became popular knowledge. Now, dairy products and their link to hormonally sensitive cancers is on his radar. While dermatologists routinely advise patients to get their vitamin D from dietary sources instead of sunlight, Bibb doesn't want them getting it from yogurt and cheese.
He's working on a book titled "Death by Dairy" to warn consumers about a possible dietary danger.
Poison in children's clothing is emerging as the latest health risk from China.
TV3's Target programme will this week detail how scientists found formaldehyde in woollen and cotton clothes at levels 500 times higher than is safe.
It questions why there are no New Zealand safety standards for clothes.
While nicotine is highly addictive, researchers have also shown the drug to enhance learning and memory - a property that has launched efforts to develop nicotine-like drugs to treat cognitive deficits in Alzheimer's and Parkinson's diseases, schizophrenia, and attention-deficit/hyperactivity disorder.
A key problem in designing such drugs has been that little was known about the detailed mechanism by which nicotine exerts its learning-enhancing effects.
Now, researchers have discovered important details of how nicotine adjusts the signaling properties of neuronal wiring to enhance memory. Such signaling properties include the strength of the connections by which one neuron triggers another. Huibert Mansvelder and colleagues reported their findings in the April 5, 2007, issue of the journal Neuron, published by Cell Press.
Scientists know that information travels between brain cells along hairlike extensions called axons. For the first time, researchers have found that axons don't just transmit information - they can turn the signal up or down with the right stimulation.
This finding may help scientists develop treatments for psychiatric disorders such as depression and schizophrenia in which it is thought that different parts of the brain do not communicate correctly with each other.
"Until now, scientists have thought that in the brain's cortex -- where most cognitive processes occur -- information was only processed in the cell body," said Raju Metherate, author of the study, associate professor of neurobiology and behavior, and director of the Center for Hearing Research at UC Irvine. "The result of our study suggests that we must consider the axons as sites of information processing - and of potential problems when things go wrong."
This study appears online Aug. 19 in Nature Neuroscience.