Recent research in rats suggests that nicotine mimics the effects of hypocretin, a protein thought to help regulate sleep and wakefulness, in the prefrontal cortex, a part of the brain important in tasks requiring attention.
In the study, 10 adult male rats were trained to pay attention to a visual stimulus, upon which they would poke a target and be rewarded with food. After learning the task, the prefrontal cortices of all 10 rats were successively infused with saline, nicotine, and a low or high dose of hypocretin.
The researchers found that infusions of both nicotine and hypocretin improved the ability of the rats to pay attention and follow through on a task, even when conditions were demanding. Further analyses showed that nicotine and the higher dose of hypocretin improved accuracy in the task under the most demanding condition.
This is the first study to suggest that hypocretin plays a role in attention, and further demonstrates that hypocretin and nicotine act similarly to enhance attention and performance.
The study, led by Dr. Evelyn Lambe of Yale University School of Medicine, was published in the May 25, 2005 issue of the Journal of Neuroscience.