refore, may be more susceptible to drugs that activate the dopamine system, such as cocaine, alcohol, amphetamine and, to a lesser extent, opiates and nicotine. One theory is that different dopamine receptors in the brain may be related to different types of abuse and that people who have particularly low dopamine functioning may be more susceptible to depression and Parkinson's disease.
In related research, Depue has shown that dopamine is strongly related to how well the prefrontal cortex holds information. "To hold in short-term memory a spatial map of the environment, for example, you must have the dopamine system activated; without it, you can't do this type of cognitive functioning," Depue concludes from his research in this area.
Depue now is measuring the emotional responses of volunteers to emotional film clips before and after their dopamine systems have been stimulated or with the use of a placebo.
Depue's work is supported, in part, with grants from the National Institute of Mental Health.