Cognitive flexibility in phenotypes of pediatric bipolar disorder.
OBJECTIVE
Clinicians and researchers debate whether children with chronic, nonepisodic irritability should receive the diagnosis of bipolar disorder (BD). To address this debate, we evaluated cognitive flexibility, or the ability to adapt to changing contingencies, in three groups of children: narrow-phenotype BD (NP-BD; full-duration manic episodes of elevated/expansive mood; N = 50; 13.1 +/- 2.9 years), severe mood dysregulation (SMD; chronic, nonepisodic irritability; N = 44; 12.2 +/- 2.1 years), and healthy controls (N = 43; 13.6 +/- 2.4 years). Cognitive flexibility is relevant to symptoms of BD involving dysfunctional reward systems (e.g., excessive goal-directed activity and pleasure-seeking in mania; anhedonia in depression).


METHODS
We studied simple and compound reversal stages of the intra-/extradimensional shift task and change task that involves inhibiting a prepotent response and substituting a novel response.


RESULTS
On the simple reversal, NP-BD youths were significantly more impaired than both the SMD group and controls. On the compound reversal, NP-BD and SMD youths performed worse than controls. On the change task, NP-BD youths were slower to adapt than SMD subjects.


CONCLUSIONS
Phenotypic differences in cognitive flexibility may reflect different brain/behavior mechanisms in these two patient populations.
Dickstein
Daniel P
DP
All authors were affiliated with the National Institute of Mental Health (NIMH) Division of Intramural Research Program when this work was prepared; Dr. McClure is currently with the Department of Psychology, Georgia State University. Electronic address: Dicksted@mail.nih.gov.
Nelson
Eric E
EE
All authors were affiliated with the National Institute of Mental Health (NIMH) Division of Intramural Research Program when this work was prepared; Dr. McClure is currently with the Department of Psychology, Georgia State University.
McCLURE
Erin B
EB
All authors were affiliated with the National Institute of Mental Health (NIMH) Division of Intramural Research Program when this work was prepared; Dr. McClure is currently with the Department of Psychology, Georgia State University.
Grimley
Mary E
ME
All authors were affiliated with the National Institute of Mental Health (NIMH) Division of Intramural Research Program when this work was prepared; Dr. McClure is currently with the Department of Psychology, Georgia State University.
Knopf
Lisa
L
All authors were affiliated with the National Institute of Mental Health (NIMH) Division of Intramural Research Program when this work was prepared; Dr. McClure is currently with the Department of Psychology, Georgia State University.
Brotman
Melissa A
MA
All authors were affiliated with the National Institute of Mental Health (NIMH) Division of Intramural Research Program when this work was prepared; Dr. McClure is currently with the Department of Psychology, Georgia State University.
Rich
Brendan A
BA
All authors were affiliated with the National Institute of Mental Health (NIMH) Division of Intramural Research Program when this work was prepared; Dr. McClure is currently with the Department of Psychology, Georgia State University.
Pine
Daniel S
DS
All authors were affiliated with the National Institute of Mental Health (NIMH) Division of Intramural Research Program when this work was prepared; Dr. McClure is currently with the Department of Psychology, Georgia State University.
Leibenluft
Ellen
E
All authors were affiliated with the National Institute of Mental Health (NIMH) Division of Intramural Research Program when this work was prepared; Dr. McClure is currently with the Department of Psychology, Georgia State University.
D000293:Adolescent; D001714:Bipolar Disorder / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology; D002648:Child; D003072:Cognition Disorders / Q000175:diagnosis / Q000453:epidemiology*; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D006801:Humans; D015994:Incidence; D007508:Irritable Mood; D008297:Male; D009483:Neuropsychological Tests; D010507:Periodicity; D010641:Phenotype; D015995:Prevalence; D012720:Severity of Illness Index