Susan B. Perlman

Abnormally Reduced Dorsomedial Prefrontal Cortical Activity and Effective Connectivity With Amygdala in Response to Negative Emotional Faces in Postpartum Depression

OBJECTIVE Postpartum major depression is a significant public health problem that strikes 15% of new mothers and confers adverse consequences for mothers, children, and families. The neural mechanisms involved in postpartum depression remain unknown, but brain processing of affective stimuli appears to be involved in other affective disorders. The authors examined activity in response to negative emotional faces in the dorsomedial pre-frontal cortex and amygdala, key emotion regulatory neural regions of importance to both mothering and depression. METHOD Postpartum healthy mothers (N=16) and unmedicated depressed mothers (N=14) underwent functional magnetic resonance imaging blood-oxygen-level-dependent acquisition during a block-designed face versus shape matching task. A two-way analysis of variance was performed examining main effects of condition and group and group-by-condition interaction on activity in bilateral dorsomedial prefrontal cortical and amygdala regions of interest. RESULTS Depressed mothers relative to healthy mothers had significantly reduced left dorsomedial prefrontal cortical face-related activity. In depressed mothers, there was also a significant negative correlation between left amygdala activity and postpartum depression severity and a significant positive correlation between right amygdala activity and absence of infant-related hostility. There was reliable top-down connectivity from the left dorsomedial prefrontal cortex to the left amygdala in healthy, but not depressed, mothers. CONCLUSIONS Significantly diminished dorsomedial prefrontal cortex activity and dorsomedial prefrontal cortical-amygdala effective connectivity in response to negative emotional faces may represent an important neural mechanism, or effect, of postpartum depression. Reduced amygdala activity in response to negative emotional faces is associated with greater postpartum depression severity and more impaired maternal attachment processes in postpartum depressed mothers.

Experimental manipulation of face-evoked activity in the fusiform gyrus of individuals with autism.

Previous research suggests hypoactivity in response to the visual perception of faces in the fusiform gyri and amygdalae of individuals with autism. However, critical questions remain regarding the mechanisms underlying these findings. In particular, to what degree is the hypoactivation accounted for by known differences in the visual scanpaths exhibited by individuals with and without autism in response to faces? Here, using functional magnetic resonance imaging, we report “normalization” of activity in the right fusiform gyrus, but not the amygdalae, when individuals with autism were compelled to perform visual scanpaths that involved fixating on the eyes of a fearful face. These findings hold important implications for our understanding of social brain dysfunction in autism, theories of the role of the fusiform gyri in face processing, and the design of more effective interventions for autism.

Amygdala activity and prefrontal cortex–amygdala effective connectivity to emerging emotional faces distinguish remitted and depressed mood states in bipolar disorder

Perlman SB, Almeida JRC, Kronhaus DM, Versace A, LaBarbara EJ, Klein CR, Phillips ML. Amygdala activity and prefrontal cortex–amygdala effective connectivity to emerging emotional faces distinguish remitted and depressed mood states in bipolar disorder. Bipolar Disord 2012: 14: 162–174.

Parsing Dimensional vs Diagnostic Category–Related Patterns of Reward Circuitry Function in Behaviorally and Emotionally Dysregulated Youth in the Longitudinal Assessment of Manic Symptoms Study

IMPORTANCE Pediatric disorders characterized by behavioral and emotional dysregulation pose diagnostic and treatment challenges because of high comorbidity, suggesting that they may be better conceptualized dimensionally rather than categorically. Identifying neuroimaging measures associated with behavioral and emotional dysregulation in youth may inform understanding of underlying dimensional vs disorder-specific pathophysiologic features. OBJECTIVE To identify, in a large cohort of behaviorally and emotionally dysregulated youth, neuroimaging measures that (1) are associated with behavioral and emotional dysregulation pathologic dimensions (behavioral and emotional dysregulation measured with the Parent General Behavior Inventory 10-Item Mania Scale [PGBI-10M], mania, depression, and anxiety) or (2) differentiate diagnostic categories (bipolar spectrum disorders, attention-deficit/hyperactivity disorder, anxiety, and disruptive behavior disorders). DESIGN, SETTING, AND PARTICIPANTS A multisite neuroimaging study was conducted from February 1, 2011, to April 15, 2012, at 3 academic medical centers: University Hospitals Case Medical Center, Cincinnati Childrens Hospital Medical Center, and University of Pittsburgh Medical Center. Participants included a referred sample of behaviorally and emotionally dysregulated youth from the Longitudinal Assessment of Manic Symptoms (LAMS) study (n = 85) and healthy youth (n = 20). MAIN OUTCOMES AND MEASURES Region-of-interest analyses examined relationships among prefrontal-ventral striatal reward circuitry during a reward paradigm (win, loss, and control conditions), symptom dimensions, and diagnostic categories. RESULTS Regardless of diagnosis, higher PGBI-10M scores were associated with greater left middle prefrontal cortical activity (r = 0.28) and anxiety with greater right dorsal anterior cingulate cortical (r = 0.27) activity to win. The 20 highest (t = 2.75) and 20 lowest (t = 2.42) PGBI-10M-scoring youth showed significantly greater left middle prefrontal cortical activity to win compared with 20 healthy youth. Disruptive behavior disorders were associated with lower left ventrolateral prefrontal cortex activity to win (t = 2.68) (all P < .05, corrected). CONCLUSIONS AND RELEVANCE Greater PGBI-10M-related left middle prefrontal cortical activity and anxiety-related right dorsal anterior cingulate cortical activity to win may reflect heightened reward sensitivity and greater attention to reward in behaviorally and emotionally dysregulated youth regardless of diagnosis. Reduced left ventrolateral prefrontal cortex activity to win may reflect reward insensitivity in youth with disruptive behavior disorders. Despite a distinct reward-related neurophysiologic feature in disruptive behavior disorders, findings generally support a dimensional approach to studying neural mechanisms in behaviorally and emotionally dysregulated youth.

Neural substrates of child irritability in typically developing and psychiatric populations

Highlights • This study compared children (ages 6–9) with clinically high irritability to healthy children.• A novel and child-friendly task induced frustration during fMRI scanning.• Results indicated differential activation of the ACC and PCC in clinical children.• Activation in the ACC and striatum during frustration varied dimensionally with irritability.• Results indicate deviation in reward and emotional function in irritable children.

Functional Near-Infrared Spectroscopy Evidence for Development of Prefrontal Engagement in Working Memory in Early Through Middle Childhood

The neural underpinnings of working memory are hypothesized to develop incrementally across preschool and early school age, coinciding with the rapid maturation of executive function occurring during this period. This study investigates the development of prefrontal cortex function between the ages of 3 and 7. Children (n = 68) participated in a novel spatial working memory task while their middle and lateral prefrontal cortex (LPFC) was monitored using functional near infrared spectroscopy (fNIRS). We found increased activation of the LPFC when comparing working memory to rest. Greater LPFC increase was noted for longer compared with shorter delay periods. Increase in LPFC activation, accuracy, and response speed were positively correlated with child age, suggesting that developmental changes in prefrontal function might underlie effective development of executive function in this age range.

Decreased amygdala-insula resting state connectivity in behaviorally and emotionally dysregulated youth

The Research Domain Criteria (RDoC) adopts a dimensional approach for examining pathophysiological processes underlying categorically defined psychiatric diagnoses. We used this framework to examine relationships among symptom dimensions, diagnostic categories, and resting state connectivity in behaviorally and emotionally dysregulated youth selected from the Longitudinal Assessment of Manic Symptoms study (n=42) and healthy control youth (n=18). Region of interest analyses examined relationships among resting state connectivity, symptom dimensions (behavioral and emotional dysregulation measured with the Parent General Behavior Inventory-10 Item Mania Scale [PGBI-10M]; dimensional severity measures of mania, depression, anxiety), and diagnostic categories (Bipolar Spectrum Disorders, Attention Deficit Hyperactivity Disorder, Anxiety Disorders, and Disruptive Behavior Disorders). After adjusting for demographic variables, two dimensional measures showed significant inverse relationships with resting state connectivity, regardless of diagnosis: 1) PGBI-10M with amygdala-left posterior insula/bilateral putamen; and 2) depressive symptoms with amygdala-right posterior insula connectivity. Diagnostic categories showed no significant relationships with resting state connectivity. Resting state connectivity between amygdala and posterior insula decreased with increasing severity of behavioral and emotional dysregulation and depression; this suggests an intrinsic functional uncoupling of key neural regions supporting emotion processing and regulation. These findings support the RDoC dimensional approach for characterizing pathophysiologic processes that cut across different psychiatric disorders.

An fMRI study of attentional control in the context of emotional distracters in euthymic adults with bipolar disorder

Inability to modulate attention away from emotional stimuli may be a key component of dysregulated emotion in bipolar disorder (BD). Previous studies of BD indicate abnormalities in neural circuitry underlying attentional control, yet few studies examined attentional control in the context of emotional distracters. We compared activity and connectivity in neural circuitry supporting attentional control and emotion processing among 22 individuals with BD type 1, currently remitted and euthymic, and 19 healthy controls. Participants performed an emotional n-back paradigm, comprising high and low attentional demand conditions, each with either emotional (happy, fearful), neutral or no face flanker distracters. During the high attentional control demand conditions without emotional distracters, BD individuals showed reduced activity relative to controls in dorsolateral prefrontal cortex, dorsal anterior cingulate cortex (dACC), and inferior parietal cortex. During the high attentional control demand conditions with fearful-face distracters, BD individuals showed greater activity than controls in these regions and amygdala and striatum. Relative to controls, BD individuals also showed abnormal patterns of effective connectivity between dACC and amygdala during high attentional control demand with emotional face distracters. Inter-episode bipolar disorder is characterized by abnormal recruitment of attentional control neural circuitry, especially in the context of emotionally distracting information.

Emotional Face Processing in Pediatric Bipolar Disorder: Evidence for Functional Impairments in the Fusiform Gyrus

OBJECTIVE Pediatric bipolar disorder involves poor social functioning, but the neural mechanisms underlying these deficits are not well understood. Previous neuroimaging studies have found deficits in emotional face processing localized to emotional brain regions. However, few studies have examined dysfunction in other regions of the face processing circuit. This study assessed hypoactivation in key face processing regions of the brain in pediatric bipolar disorder. METHOD Youth with a bipolar spectrum diagnosis (n = 20) were matched to a nonbipolar clinical group (n = 20), with similar demographics and comorbid diagnoses, and a healthy control group (n = 20). Youth participated in a functional magnetic resonance imaging (fMRI) scanning which employed a task-irrelevant emotion processing design in which processing of facial emotions was not germane to task performance. RESULTS Hypoactivation, isolated to the fusiform gyrus, was found when viewing animated, emerging facial expressions of happiness, sadness, fearfulness, and especially anger in pediatric bipolar participants relative to matched clinical and healthy control groups. CONCLUSIONS The results of the study imply that differences exist in visual regions of the brains face processing system and are not solely isolated to emotional brain regions such as the amygdala. Findings are discussed in relation to facial emotion recognition and fusiform gyrus deficits previously reported in the autism literature. Behavioral interventions targeting attention to facial stimuli might be explored as possible treatments for bipolar disorder in youth.

Dissociable patterns of medial prefrontal and amygdala activity to face identity versus emotion in bipolar disorder

BACKGROUND Individuals with bipolar disorder demonstrate abnormal social function. Neuroimaging studies in bipolar disorder have shown functional abnormalities in neural circuitry supporting face emotion processing, but have not examined face identity processing, a key component of social function. We aimed to elucidate functional abnormalities in neural circuitry supporting face emotion and face identity processing in bipolar disorder. METHOD Twenty-seven individuals with bipolar disorder I currently euthymic and 27 healthy controls participated in an implicit face processing, block-design paradigm. Participants labeled color flashes that were superimposed on dynamically changing background faces comprising morphs either from neutral to prototypical emotion (happy, sad, angry and fearful) or from one identity to another identity depicting a neutral face. Whole-brain and amygdala region-of-interest (ROI) activities were compared between groups. RESULTS There was no significant between-group difference looking across both emerging face emotion and identity. During processing of all emerging emotions, euthymic individuals with bipolar disorder showed significantly greater amygdala activity. During facial identity and also happy face processing, euthymic individuals with bipolar disorder showed significantly greater amygdala and medial prefrontal cortical activity compared with controls. CONCLUSIONS This is the first study to examine neural circuitry supporting face identity and face emotion processing in bipolar disorder. Our findings of abnormally elevated activity in amygdala and medial prefrontal cortex (mPFC) during face identity and happy face emotion processing suggest functional abnormalities in key regions previously implicated in social processing. This may be of future importance toward examining the abnormal self-related processing, grandiosity and social dysfunction seen in bipolar disorder.