Neuropsychological and behavioural disinhibition in adult ADHD compared to borderline personality disorder.
BACKGROUND
Although attention-deficit/hyperactivity disorder (ADHD) is thought to be an inhibitory disorder, the question remains of how specific the inhibitory deficit is in adults and whether it distinguishes ADHD from borderline personality disorder (BPD), with which it shares several clinical features, particularly impulsiveness.


METHODS
The study assessed various motor and cognitive inhibitory functions (inhibition of prepotent, ongoing and interfering responses) in addition to working memory in adult ADHD patients with and without BPD, compared to subjects with BPD alone and controls. In addition, questionnaire data on various aspects of impulsiveness and anger regulation were assessed in all groups.


RESULTS
ADHD patients performed worse than BPD individuals and controls in two inhibitory tasks: the stop signal task and the conflict module of the Attentional Network Task (ANT). In addition, they exhibited longer reaction times (RTs) and higher intra-individual variance in nearly all attentional tasks. The co-morbid group exhibited poor performance on the stop signal task but not on the conflict task. The BPD group barely differed from controls in neuropsychological performance but overlapped with ADHD in some behavioural problems, although they were less severe on the whole.


CONCLUSIONS
Impaired inhibition is a core feature in adults with ADHD. In addition, slow RTs and high intra-individual variance in performance may reflect deficits in the regulation of activation and effort in ADHD patients. ADHD and BPD share some symptoms of behavioural dysregulation without common cognitive deficits, at least in the attentional realm.
Lampe
K
K
Department of Psychiatry and Psychotherapy, RWTH Aachen, University Hospital, Rostock, Germany.
Konrad
K
K
Kroener
S
S
Fast
K
K
Kunert
H J
HJ
Herpertz
S C
SC
D000293:Adolescent; D000328:Adult; D000786:Anger; D001288:Attention; D001289:Attention Deficit Disorder with Hyperactivity / Q000175:diagnosis* / Q000523:psychology; D001883:Borderline Personality Disorder / Q000175:diagnosis* / Q000523:psychology; D015897:Comorbidity; D003220:Conflict, Psychological; D005260:Female; D006801:Humans; D007175:Impulsive Behavior / Q000175:diagnosis / Q000523:psychology; D007266:Inhibition, Psychological; D008297:Male; D008570:Memory, Short-Term; D001523:Mental Disorders / Q000175:diagnosis* / Q000523:psychology; D008875:Middle Aged; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D011594:Psychometrics; D011597:Psychomotor Performance; D011930:Reaction Time