‘Defective brain’ causes impulsive acts. The BBC bills it this way: “Scientists at Cambridge University believe they

have discovered the part of the brain

associated with impulsive behaviour.” The nucleus accumbens doesn’t function properly, as evidenced on fMRI scans, in extremely impulsive people who “can’t help it.” Rats which underwent n. accumbens lesioning were unable to delay gratification. The BBC article concludes that this is evidence of a “strong biological and, therefore, genetic basis to impulsive behavior.” Extremely reductionistic and misleading reasoning. To start simple, biological does not equal genetically based. The rats’ injuries were biological but acquired, not inherited.Organic injury, especially to frontal lobe structures, often causes impulsivity; most neurobehavioral conditions causing dyscontrol are acquired but not inherited. ADHD may have a heritable component but it’s not clear if it is primarily an impulse disorder, or if it’s even one homogeneous disorder at all. I’ve been studying, treating and writing aabout adult ADHD for more than a decade and I don’t believe it is. Don’t get me started on the absurdities of the current ADHD bandwagon fad!

Doubtlessly it is not a single small structure but the concerted action of many frontal structures that helps us with being planful, maintaining set, inhibiting urges, and deferring gratification, all parts of the complex human capacity for “impulse control.”