Article

Relation between amygdala structure and function in adolescents with bipolar disorder.

Department of Psychiatry, Yale School of Medicine, 300 George Street, Suite 901, New Haven, CT 06511, USA.
Journal of the American Academy of Child and Adolescent Psychiatry (Impact Factor: 6.35). 07/2009; 48(6):636-42. DOI: 10.1097/CHI.0b013e31819f6fbc
Source: PubMed

ABSTRACT Previous study supports the presence of reduced volume and elevated response to emotional stimuli in amygdala in adolescents with bipolar disorder (BD). In the present study, structural and functional magnetic resonance imaging scans were obtained during the same neuroimaging session to examine amygdala structure-function relations in adolescents with BD. We hypothesized that amygdala volume would be inversely associated with amygdala response to emotional stimuli, such that BD participants with the smallest amygdala volumes would exhibit the highest amygdala response.
Fifty-one adolescents (21 with BD I and 30 control adolescents, ages 10-18 years) underwent structural and functional magnetic resonance imaging scans. Amygdala volume (n = 49) and signal change (n = 44) during emotional face processing were compared between groups, and structure-function correlations were examined within the BD group (n = 16).
Adolescents with BD showed decreased amygdala volume (p =.009) and increased amygdala response to emotional faces (p =.043). There was no significant interaction between diagnosis and emotion type. A significant inverse association between amygdala volume and activation during emotional face processing was observed (r = -0.54, p =.029).
Decreased volume and increased response to emotional stimuli in the amygdala in adolescents with BD are consistent with previous reports. This study represents the first report, to our knowledge, of the two findings in the same adolescent BD sample and supports an amygdala structure-function relation characterized by an inverse association between volume and response to emotional stimuli. This preliminary finding requires replication and suggests a possible pathophysiological link between abnormalities in amygdala structure and response to emotional stimuli in BD.

Download full-text

Full-text

Available from: Robert Todd Constable, Jun 11, 2015
0 Followers
 · 
131 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Research in bipolar disorder (BD) implicates fronto-limbic-striatal dysfunction during face emotion processing but it is unknown how such dysfunction varies by task demands, face emotion and patient age. Method During functional magnetic resonance imaging (fMRI), 181 participants, including 62 BD (36 children and 26 adults) and 119 healthy comparison (HC) subjects (57 children and 62 adults), engaged in constrained and unconstrained processing of emotional (angry, fearful, happy) and non-emotional (neutral) faces. During constrained processing, subjects answered questions focusing their attention on the face; this was processed either implicitly (nose width rating) or explicitly (hostility; subjective fear ratings). Unconstrained processing consisted of passive viewing. Pediatric BD rated neutral faces as more hostile than did other groups. In BD patients, family-wise error (FWE)-corrected region of interest (ROI) analyses revealed dysfunction in the amygdala, inferior frontal gyrus (IFG), anterior cingulate cortex (ACC) and putamen. Patients with BD showed amygdala hyperactivation during explicit processing (hostility ratings) of fearful faces and passive viewing of angry and neutral faces but IFG hypoactivation during implicit processing of neutral and happy faces. In the ACC and striatum, the direction of dysfunction varied by task demand: BD demonstrated hyperactivation during unconstrained processing of angry or neutral faces but hypoactivation during constrained processing (implicit or explicit) of angry, neutral or happy faces. Findings suggest amygdala hyperactivation in BD while processing negatively valenced and neutral faces, regardless of attentional condition, and BD IFG hypoactivation during implicit processing. In the cognitive control circuit involving the ACC and putamen, BD neural dysfunction was sensitive to task demands.
    Psychological Medicine 08/2013; DOI:10.1017/S003329171300202X · 5.43 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Abstract Background: Inpatient aggression is a serious challenge in pediatric psychiatry. Methods: A chart review study in adolescent psychiatric inpatients consecutively admitted over 24 months was conducted, to describe aggressive events requiring an intervention (AERI) and to characterize their management. AERIs were identified based on specific institutional event forms and/or documentation of as-needed (STAT/PRN) medication administration for aggression, both recorded by nursing staff. Results: Among 408 adolescent inpatients (age: 15.2±1.6 years, 43.9% male), 1349 AERIs were recorded, with ≥1 AERI occurring in 28.4% (n=116; AERI+). However, the frequency of AERIs was highly skewed (median 4, range: 1-258). In a logistical regression model, the primary diagnosis at discharge of disruptive behavior disorders and bipolar disorders, history of previous inpatient treatment, length of hospitalization, and absence of a specific precipitant prior to admission were significantly associated with AERIs (R(2)=0.32; p<0.0001). The first line treatment of patients with AERIs (AERI+) was pharmacological in nature (95.6%). Seclusion or restraint (SRU) was used at least once in 59.4% of the AERI+ subgroup (i.e., in 16.9% of all patients; median within-group SRU frequency: 3). Treatment and discharge characteristics indicated a poorer prognosis in the AERI+ (discharge to residential care AERI+: 22.8%, AERI-: 5.6%, p<0.001) and a greater need for psychotropic polypharmacy (median number of psychotropic medications AERI+: 2; AERI-: 1, p<0.001). Conclusions: Despite high rates of pharmacological interventions, SRU continue to be used in adolescent inpatient care. As both of these approaches lack a clear evidence base, and as adolescents with clinically significant inpatient aggression have increased illness acuity/severity and service needs, structured research into the most appropriate inpatient aggression management is sorely needed.
    Journal of child and adolescent psychopharmacology 05/2013; DOI:10.1089/cap.2012.0116 · 3.07 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A major controversy in child psychiatry is whether bipolar disorder (BD) presents in children as severe, non-episodic irritability (operationalized here as severe mood dysregulation, SMD), rather than with manic episodes as in adults. Both classic, episodic BD and SMD are severe mood disorders characterized by deficits in processing emotional stimuli. Neuroimaging techniques can be used to test whether the pathophysiology mediating these deficits are similar across the two phenotypes. Amygdala dysfunction during face emotion processing is well-documented in BD, but little is known about amygdala dysfunction in chronically irritable youth. We compared neural activation in SMD (n=19), BD (n=19), and healthy volunteer (HV; n=15) youths during an implicit face-emotion processing task with angry, fearful and neutral expressions. In the right amygdala, both SMD and BD exhibited greater activity across all expressions than HV. However, SMD and BD differed from each other and HV in posterior cingulate cortex, posterior insula, and inferior parietal lobe. In these regions, only SMD showed deactivation in response to fearful expressions, whereas only BD showed deactivation in response to angry expressions. Thus, during implicit face emotion processing, youth with BD and those with SMD exhibit similar amygdala dysfunction but different abnormalities in regions involved in information monitoring and integration.
    01/2013; 2:637-645. DOI:10.1016/j.nicl.2013.04.007