Could changing the brain help smokers quit?

The transcranial direct current brain stimulation test developed by Penn researcher Caryn Lerman is demonstrated by Becky Ashare.

Psychologist Caryn Lerman spent decades studying how people react when they learn their behavior has put them at high risk of developing cancer. But education, she saw early on, isn't enough to help some smokers kick the habit.

"The motivation to quit became stronger and they tried to quit more times, but they actually were unable to," said Lerman, who is now senior deputy director of the University of Pennsylvania's Abramson Cancer Center.

"I then became very interested in why it was so hard to quit smoking. It's not a lack of knowledge. It's not that they don't have the right motivation."

That led to her current quest: figuring out how to change the way people think - literally changing the brain with electricity or cognitive exercises - to combat behaviors that increase risk for cancer. She recently won a $6.5 million, seven-year Outstanding Investigator Award from the National Cancer Institute, a new grant meant to free seasoned researchers from the constant need to seek funding while they pursue solutions to complex problems.

Lerman's research will focus on smoking and obesity, which account for more than 45 percent of preventable cancer deaths. They are interrelated, because people often gain weight when they stop smoking. In addition, she said, eating certain kinds of foods - think high fat and high sugar - can activate the same reward circuits in the brain as addictive substances.

Most grants make researchers stick to rigid protocols. This one, Lerman said, will let her "follow the science."

Her recent work has looked at the role of the dorsolateral prefrontal cortex, a region of the brain located behind the forehead that is key to planning and self-control. Activity in this region tends to weaken when people are withdrawing from cigarettes, a time when addicts most need to focus on long-term goals rather than giving in to cravings.

She is now testing whether cognitive activities aimed at strengthening brain functioning or zapping the brain with a low level of electricity can make it easier for people to withstand cravings.

Brain training has been shown to improve memory and attention, but "there is no strong evidence that cognitive exercise training can change addictive behaviors," Lerman said.

She will be testing it in conjunction with transcranial direct current brain stimulation (tDCS), the electrical approach, aimed at the dorsolateral prefrontal cortex.

This treatment grew out of deep brain stimulation and transcranial magnetic stimulation, but uses much simpler, less invasive equipment. Patients feel a mild tingling from two electrodes strapped to their forehead. The system delivers 1 milliamp of electricity, less than one one-hundredth of what would be used in shock therapy, Lerman said.

"There is some evidence that if you stimulate some of the cortical circuits, you can improve cognitive performance and possibly influence decision-making in positive ways, but this is a very nascent field right now," Lerman said.

Her most recent study tested about 25 smokers who were not trying to quit, but had gone 14 hours without a cigarette before coming to the lab. They were hooked to the real stimulator or given a placebo experience while trying not to smoke. The researchers offered their favorite brand, but also paid them $1 for every five minutes they didn't smoke.

Lerman said the theory is that the electrical current helps strengthen brain pathways that are being used. The machines wouldn't help you unless you were engaged in a type of thinking you wanted to reinforce and it was taking place in the targeted part of the brain.

That study hasn't been published yet, but Lerman said a 20-minute stimulator session increased the time it took for study participants to light up and reduced the number of cigarettes they smoked.

Few of them could resist smoking for an hour.

Karen O'Brien, a Warminster woman who has smoked for nearly 40 of her 53 years, managed not to smoke Pall Mall Blues when she participated in the study last spring. She was told she could smoke as many of them as she wanted, but couldn't take any with her. Talk about temptation.

She doesn't know for sure whether she got the active treatment, but she found she just didn't want to smoke in the little study room.

"I often wondered if the stimulus had anything to do with it," she said.

Asked how long she went without a cigarette after she left the lab. O'Brien said 25 minutes. "Maybe not that long," she amended. "Maybe 10 minutes.

O'Brien, who has quit for long periods several times, is eager to participate when Lerman begins her study of people who want to stop smoking.

Asked whether there might be demand for cognitive stimulation from all sorts of people who would like to improve how their brains work, Lerman downplayed the science fiction-like potential of her work. The machines, she said, are likely to produce "relatively mild enhancements as opposed to creating super humans."

Lerman's lab will be recruiting smokers who want to quit next month and obese participants early next year. For information on participating in Lerman's studies, go to http://www.phillybrainpower.com/


sburling@phillynews.com

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@StaceyABurling