Nicotine’s "cognitive qualities"

I am so confused by this article.

New scientific find may help smokers quit

In a study that may hold insights into ways to help people quit smoking, researchers at the CNRS-Pasteur Institute in Paris showed that receptors on cells in the ventral tegmental area (VTA) of the brain are involved in nicotine’s addictive and cognitive qualities in mice.

[…]

Changeux and his team genetically engineered mice so they lacked a gene for a portion of a nicotine receptor, to discover the impact it would have on how the mice functioned.

The mutant mice had a mild learning impairment and unlike normal mice, which had learned to press a lever to self-administer nicotine, they showed no interest in getting nicotine.

“When there is a loss of the nicotine receptor then there is a loss of cognitive function in the mouse,” Changeux, who reported the finding in the science journal Nature, told Reuters.

But when the scientists re-injected the gene, the mice’s cognitive function was restored. The rodents were also more likely to seek out nicotine.

They think this research could lead to a way to help smokers quit. But I ask you: how? By giving people learning disabilities?

I mean, really; is this article just horribly written? Obviously it is–just try and interpret the first sentence. But is it so horribly written that important facts vital to comprehension of the meaning of this study are omitted? Or am I missing something?

If cognitive function and nicotine receptors are inextricably linked, what does this mean? Is cognitive function affected by whether or not a person smokes, or only by whether or not they have nicotine receptors? And what do they mean by “mild learning impairment”? How mild, exactly? I don’t smoke, so this is all academic, but if I did, I can’t imagine that any level of “learning impairment” would be acceptable to me.