Results : In ADHD , deviant prefrontal and cingulate functional activity was associated with increased IA .
Structural alterations were most pronounced in the cingulate cortex .
Subjects with DBDs showed marked cortico‐subcortical dysfunctions .
ADHD and DBDs share similar cortico‐limbic structural and functional alterations .
RI deficits in ADHD highlighted hypoactivity in the dorso/ventro‐lateral PFC , insula , and striatum , while the paralimbic system was primarily dysfunctional in DBDs .
Across disorders , extensively altered cortico‐limbic dysfunctions underlie IA , while RI was mostly associated with aberrant prefrontal activity .
Conclusion : Control network deficits were evidence d across clinical phenotypes in IA and RI .
Dysfunctions at any level within these cortico‐subcortical projections lead to deficient cognitive‐affective control by ascribing emotional salience to otherwise irrelevant stimuli .
HighlightsImpulsive aggression and dysfunctional response inhibition are present in ADHD and DBDs .
Broad fronto‐striatal‐cerebellar dysfunctions have been implicated in ADHD and DBDs .
Prefrontal and cingulate cortical deficits are associated with IA in ADHD.Severe widespread cortico‐subcortical breakdowns are associated with IA in DBDs .
RI deficits have been attributed to hypoactivity in the lateral PFC , insula , and amygdala .
Whether reduced gray matter volumes relate to ADHD and DBDs or if present as an IA epiphenomenon remains debatable .
Background : Although impulsive aggression ( IA ) and dysfunctional response inhibition ( RI ) are hallmarks of attention‐deficit/hyperactivity disorder ( ADHD ) and disrupted behavioral disorders ( DBDs ) , little is known about their shared and distinct deviant neural mechanisms .
Effects of smoking different doses of nicotine on human aggressive behavior
A new methodology was employed to study the effects of drugs on human aggressive behavior  in a laboratory situation . The effects of not smoking , smoking a  low nicotine dose ( 0.42 mg/cigarette ) , and smoking a  high nicotine dose ( 2.19 mg/cigarette ) on human nonaggressive and aggressive responding was determined . A nonaggressive response , which result ed in the accumulation of money , was continuously available to the subject . Two different aggressive responses were also available : the ostensible subtraction of money from , and the ostensible presentation of a 1-s blast of white noise to a ( fictitious ) person . Aggressive responding was elicited by subtracting money from the research subjects , which was attributed to a fictitious person paired with the research subject r and omly each day . Nicotine , administered with experimental cigarettes , produced dose-dependent decreases in both types of aggressive responding elicited by low or high frequency subtractions of money attributed to another person . Generally , the more aggressive response option , i.e. , subtraction of money from another person , decreased more following nicotine administration . Smoking the same doses of nicotine increased nonaggressive monetary reinforced responding . This indicates that the suppressant effect of nicotine on aggressive responding was not due to a nonspecific depressant action
Results : In ADHD , deviant prefrontal and cingulate functional activity was associated with increased IA .
Structural alterations were most pronounced in the cingulate cortex .
Subjects with DBDs showed marked cortico‐subcortical dysfunctions .
ADHD and DBDs share similar cortico‐limbic structural and functional alterations .
RI deficits in ADHD highlighted hypoactivity in the dorso/ventro‐lateral PFC , insula , and striatum , while the paralimbic system was primarily dysfunctional in DBDs .
Across disorders , extensively altered cortico‐limbic dysfunctions underlie IA , while RI was mostly associated with aberrant prefrontal activity .
Conclusion : Control network deficits were evidence d across clinical phenotypes in IA and RI .
Dysfunctions at any level within these cortico‐subcortical projections lead to deficient cognitive‐affective control by ascribing emotional salience to otherwise irrelevant stimuli .
HighlightsImpulsive aggression and dysfunctional response inhibition are present in ADHD and DBDs .
Broad fronto‐striatal‐cerebellar dysfunctions have been implicated in ADHD and DBDs .
Prefrontal and cingulate cortical deficits are associated with IA in ADHD.Severe widespread cortico‐subcortical breakdowns are associated with IA in DBDs .
RI deficits have been attributed to hypoactivity in the lateral PFC , insula , and amygdala .
Whether reduced gray matter volumes relate to ADHD and DBDs or if present as an IA epiphenomenon remains debatable .
Background : Although impulsive aggression ( IA ) and dysfunctional response inhibition ( RI ) are hallmarks of attention‐deficit/hyperactivity disorder ( ADHD ) and disrupted behavioral disorders ( DBDs ) , little is known about their shared and distinct deviant neural mechanisms .