PubMed Health⌕ Search

Biomedical subjects

Helen S Mayberg

Publications and source records attributed to Helen S Mayberg.

At least 19 recordsLinked to original sources

Changes in regional cerebral blood flow following mood challenge in drug-free, remitted patients with unipolar depression.

Studies of mood provocation in remitted patients with depression have enabled the description of specific brain changes relevant to depression relapse vulnerability. Because patients in these studies were also receiving maintenance pharmacotherapy, the ability to subtract out the drug effect from the changes observed is reduced. Our study addresses this concern. Changes in regional cerebral blood flow (rCBF) among 11 medication-free, remitted patients with unipolar depression relative to baseline state were assessed with [(15)O]H(2)O positron emission tomography (PET) following provocation of sadness. Participants showed decreased activation in prefrontal cortex similar to those reported for remitted, medicated patients undergoing mood challenge, as well as for acutely depressed patients who were medication free. Previously reported mediofrontal changes in remitted patients are unlikely to be a consequence of maintenance medication and more likely are evidence of relapse vulnerability.

Adult↗

VNS therapy in treatment-resistant depression: clinical evidence and putative neurobiological mechanisms.

Currently available therapeutic interventions for treatment-resistant depression, including switch, combination, and augmentation strategies, are less than ideal. Observations of mood elevation during vagus nerve stimulation (VNS) therapy for pharmacoresistant epilepsy suggested a role for VNS therapy in refractory major depression and prompted clinical investigation of this neurostimulation modality. The VNS Therapy System has been available for treatment of pharmacoresistant epilepsy since 1997 and was approved by the US Food and Drug Administration for treatment-resistant depression in July, 2005. The physiology of the vagus nerve, mechanics of the VNS Therapy System, and efficacy and safety in pharmacoresistant epilepsy are reviewed. Promising results of VNS therapy for treatment-resistant depression have been forthcoming from both acute and long-term studies, evidenced in part by progressive improvements in depression rating scale scores during the 1st year of treatment with maintenance of response thereafter. VNS therapy is well tolerated in patients with either pharmacoresistant epilepsy or treatment-resistant depression. As in epilepsy, the mechanisms of VNS therapy of treatment-resistant depression are incompletely understood. However, evidence from neuroimaging and other studies suggests that VNS therapy acts via innervation of the nucleus tractus solitarius, with secondary projections to limbic and cortical structures that are involved in mood regulation, including brainstem regions that contain serotonergic (raphe nucleus) and noradrenergic (locus ceruleus) perikarya that project to the forebrain. Mechanisms that mediate the beneficial effects of VNS therapy for treatment-resistant depression remain obscure. Suggestions for future research directions are described.

Animals↗

Risk and resilience markers in bipolar disorder: brain responses to emotional challenge in bipolar patients and their healthy siblings.

OBJECTIVE: The authors previously identified depression-specific differences in brain responses to an emotional challenge in patients with bipolar and unipolar mood disorder. In this study, potential markers of bipolar risk and resilience were examined in a new cohort of lithium-responsive bipolar patients and their healthy siblings. METHOD: Changes in regional cerebral blood flow (rCBF) were measured with [(15)O]water positron emission tomography after induction of transient sadness in nine euthymic lithium responders and nine healthy siblings. The patterns of change in these groups were compared, and then they were contrasted with previous findings on bipolar responders to valproate. RESULTS: Common to all three groups with induced sadness were rCBF increases in the dorsal/rostral anterior cingulate and anterior insula and decreases in the orbitofrontal and inferior temporal cortices. Distinguishing the groups were decreases in the medial frontal cortex in the patients but an increase in this region in the siblings. DISCUSSION: Common changes with emotional challenge were identified in bipolar patients and their healthy siblings. These were not seen previously in healthy subjects without a family history of mood disorder, suggesting a potential marker of bipolar risk. The siblings' unique increases in the medial frontal cortex appear to identify a compensatory response in this at-risk group, as this pattern was not seen previously in healthy subjects without depression risk factors. This differential change pattern in patients and their siblings highlights the role of the anterior cingulate and medial frontal regions in mediating resiliency and vulnerability in bipolar disorder families.

Adult↗

Posttraumatic stress disorder: a state-of-the-science review.

This article reviews the state-of-the-art research in posttraumatic stress disorder (PTSD) from several perspectives: (1) Sex differences: PTSD is more frequent among women, who tend to have different types of precipitating traumas and higher rates of comorbid panic disorder and agoraphobia than do men. (2) Risk and resilience: The presence of Group C symptoms after exposure to a disaster or act of terrorism may predict the development of PTSD as well as comorbid diagnoses. (3) Impact of trauma in early life: Persistent increases in CRF concentration are associated with early life trauma and PTSD, and may be reversed with paroxetine treatment. (4) Imaging studies: Intriguing findings in treated and untreated depressed patients may serve as a paradigm of failed brain adaptation to chronic emotional stress and anxiety disorders. (5) Neural circuits and memory: Hippocampal volume appears to be selectively decreased and hippocampal function impaired among PTSD patients. (6) Cognitive behavioral approaches: Prolonged exposure therapy, a readily disseminated treatment modality, is effective in modifying the negative cognitions that are frequent among PTSD patients. In the future, it would be useful to assess the validity of the PTSD construct, elucidate genetic and experiential contributing factors (and their complex interrelationships), clarify the mechanisms of action for different treatments used in PTSD, discover ways to predict which treatments (or treatment combinations) will be successful for a given individual, develop an operational definition of remission in PTSD, and explore ways to disseminate effective evidence-based treatments for this condition.

Adaptation, Psychological↗

Deep brain stimulation for treatment-resistant depression.

Treatment-resistant depression is a severely disabling disorder with no proven treatment options once multiple medications, psychotherapy, and electroconvulsive therapy have failed. Based on our preliminary observation that the subgenual cingulate region (Brodmann area 25) is metabolically overactive in treatment-resistant depression, we studied whether the application of chronic deep brain stimulation to modulate BA25 could reduce this elevated activity and produce clinical benefit in six patients with refractory depression. Chronic stimulation of white matter tracts adjacent to the subgenual cingulate gyrus was associated with a striking and sustained remission of depression in four of six patients. Antidepressant effects were associated with a marked reduction in local cerebral blood flow as well as changes in downstream limbic and cortical sites, measured using positron emission tomography. These results suggest that disrupting focal pathological activity in limbic-cortical circuits using electrical stimulation of the subgenual cingulate white matter can effectively reverse symptoms in otherwise treatment-resistant depression.

Adult↗

Functional neuroanatomical substrates of altered reward processing in major depressive disorder revealed by a dopaminergic probe.

CONTEXT: The pathophysiology of major depressive disorder (MDD) includes disturbances in several neuroanatomical substrates and neurotransmitter systems. The challenge is to elucidate the brain mechanisms of MDD behavioral symptoms, chiefly those of anhedonia. OBJECTIVES: To visualize the neuroanatomical substrates implicated in altered reward processing in MDD, using functional magnetic resonance imaging in combination with a dopaminergic probe (a 30-mg dose of oral dextroamphetamine sulfate) to stimulate the brain reward system; and to test the hypothesis that a hypersensitive response to dextroamphetamine in MDD involves the prefrontal cortex and the striatum. DESIGN AND INTERVENTIONS: Among subjects with MDD and healthy control subjects, functional magnetic resonance imaging data were collected before and after single-blind administration of dextroamphetamine. SETTING: Subjects were recruited through local newspaper advertisements and by word of mouth. PARTICIPANTS: Twelve depressed subjects (mean age, 34.83 years; male-female ratio, 6:6) met criteria for MDD according to the DSM-IV, were not taking antidepressants, and had no comorbid Axis I disorders. Twelve control subjects (mean age, 29.33 years; male-female ratio, 5:7) were healthy volunteers without a history of Axis I disorders. MAIN OUTCOME MEASURES: Functional magnetic resonance imaging blood oxygen level-dependent activation was measured during a controlled task, and dextroamphetamine-induced subjective effects were assessed using the Addiction Research Center Inventory. RESULTS: Subjects with MDD had a hypersensitive response to the rewarding effects of dextroamphetamine (2-fold increase; t(21) = 2.74, P = .01), with altered brain activation in the ventrolateral prefrontal cortex and the orbitofrontal cortex and the caudate and putamen (F(1,44) = 11.93, P = .001). CONCLUSION: Dopamine-related neuroanatomical substrates are involved in altered reward processing in MDD, shedding light on the neurobiology of the anhedonic symptoms in MDD and suggesting these substrates as future therapeutic targets.

Adult↗

State and trait influences on mood regulation in bipolar disorder: blood flow differences with an acute mood challenge.

BACKGROUND: Even in remission, patients with bipolar disorder (BD) remain sensitive to external stressors that can trigger new episodes. Imitating such stressors by the controlled transient exposure to an emotional stimulus may help to identify brain regions modulating this sensitivity. METHODS: Transient sadness was induced in 9 euthymic and in 11 depressed subjects with BD. Regional blood flow (rCBF) changes were measured using (15)O-water positron emission tomography. RESULTS: Common changes in both groups were increased rCBF in anterior insula and cerebellum and decreased rCBF in dorsal-ventral-medial frontal cortex, posterior cingulate, inferior parietal, and temporal cortices. Decreases in dorsal ventral medial frontal cortices occurred in both groups, but subjects in remission showed a greater magnitude of change. Unique to remitted subjects with BD were rCBF increases in dorsal anterior cingulate and in premotor cortex. Lateral prefrontal rCBF decreases were unique to depressed subjects with BD. At baseline, remitted subjects showed a unique increase in dorsal anterior cingulate and orbitofrontal cortex. CONCLUSIONS: Common rCBF changes in remitted and depressed subjects identifies potential sites of disease vulnerability. Unique cingulate and orbitofrontal changes both at baseline and with induced sadness seen in the absence of prefrontal rCBF decreases may identify regional interactions important to the euthymic state in this population.

Adult↗

Personality influences limbic-cortical interactions during sad mood induction.

The current study examined limbic-cortical activation under transient emotional stress as a function of personality style. A ventral cingulate (Cg25)-centred limbic-cortical network was identified using positron emission tomography (PET) measures of regional cerebral blood flow (rCBF) during a sad mood challenge that demonstrated differences for individuals selected for specific patterns of Negative and Positive emotional traits, indexed by the NEO Personality Inventory-Revised. Healthy subjects scoring both low on the dispositional Depression facet of Neuroticism (N3) and high on the Positive Emotions facet of Extraversion (E6) were compared to those scoring high on the Depression facet (N3) and low on Positive Emotions (E6), a combination of traits previously linked to normal variations in mood reactivity. Scan analyses were designed to further characterize known variations in Cg25 activity previously reported in studies of negative mood in both healthy subjects and depressed patients. A multivariate technique, partial least squares (PLS) demonstrated a divergent Cg25-mediated network that differentiated temperamentally negative (NAS) from temperamentally positive (PAS) subjects providing a potential neural link between these specific combinations of trait affective styles and vulnerability to depression.

Adult↗

An fMRI study investigating cognitive modulation of brain regions associated with emotional processing of visual stimuli.

Brain regions modulated by cognitive tasks during emotional processing were investigated using fMRI. Participants performed indirect and direct emotional processing tasks on positive and negative faces and pictures. We used a multivariate technique, partial least squares (PLS) to determine spatially distributed patterns of brain activity associated with different tasks and stimulus conditions, as well as the interaction between the two. The pattern of brain activity accounting for the most task-related covariance represented a task x stimulus interaction and distinguished indirect processing of pictures and direct processing of faces from direct processing of pictures and indirect processing of faces. The latter two conditions were characterised by limbic (e.g. amygdala, insula, thalamus) and temporal lobe activity, in addition to greater activity in the ventral prefrontal cortex. Indirect and direct processing of pictures and faces, respectively, were represented by more dorsal prefrontal and parietal activity. These findings indicate that brain activity during processing of emotional content is critically dependent on both the type of stimulus and processing task. In addition, these results support the idea that the pattern of activity in the emotional network can be influenced in a 'top-down' fashion via cognitive factors such as attentional control, and as such, have important clinical implications for emotional disorders, such as depression and anxiety.

Adult↗

Positron emission tomography imaging in depression: a neural systems perspective.

PET measures of regional glucose metabolism, although chemically nonspecific, are sensitive indices of brain function in the untreated state and following disparate treatments. The continued development of imaging and multivariate statistical strategies is expected to provide an important perspective toward the full characterization of the depression phenotype at the neural systems level. An additional goal is the development of routine, brain-based clinical algorithms that optimize diagnosis and treatment of individual depressed patients.

Antidepressive Agents↗

Modulating dysfunctional limbic-cortical circuits in depression: towards development of brain-based algorithms for diagnosis and optimised treatment.

While characterization of pathogenetic mechanisms underlying major depression is a fundamental aim of neuroscience research, an equally critical clinical goal is to identify biomarkers that might improve diagnostic accuracy and guide treatment selection for individual patients. To this end, a synthesis of functional neuroimaging studies examining regional metabolic and blood flow changes in depression is presented in the context of a testable limbic-cortical network model. 'Network' dysfunction combined with active intrinsic compensatory processes is seen to explain the heterogeneity of depressive symptoms observed clinically, as well as variations in pretreatment scan patterns described experimentally. Furthermore, the synchronized modulation of these dysfunctional limbic-cortical pathways is considered critical for illness remission, regardless of treatment modality. Testing of response-specific functional relationships among regional 'nodes' within this network using multivariate approaches is discussed, with a perspective aimed at identifying biomarkers of treatment non-response, relapse risk and disease vulnerability. Characterization of adaptive and maladaptive functional interactions among these pathways is seen as a critical step towards future development of evidenced-based algorithms that will optimize the diagnosis and treatment of individual depressed patients.

Algorithms↗

Cerebral metabolic correlates as potential predictors of response to anterior cingulotomy for treatment of major depression.

OBJECT: Neurosurgical procedures are a viable intervention for severe, treatment-refractory major depression, although they have been associated with only modest rates of efficacy. The purpose of this study was to identify possible neuroimaging predictors of treatment response to anterior cingulotomy in patients with major depression. METHODS: Thirteen patients underwent stereotactic anterior cingulotomy for treatment-refractory major depression. Symptom severity was measured using the Beck Depression Inventory (BDI) both before and approximately 12 months after surgery. The authors performed [18F]fluorodeoxyglucose-positron emission tomography (PET) studies in all patients preoperatively. Statistical parametric mapping methods were used to test for loci of significant correlation between preoperative regional cerebral metabolism and postoperative reduction in BDI scores. The mean (+/- standard deviation) change in the BDI score from the preoperative period (43.7 +/- 7.8) to the postoperative period (30.5 +/- 21.3) was 33.1 +/- 45.4%. Two loci--the left subgenual prefrontal cortex and left thalamus--were identified as sites at which preoperative metabolism was significantly correlated with subsequent improvement in depressive symptom severity following cingulotomy. Specifically, higher preoperative rates of metabolism at these loci were associated with better postoperative results. CONCLUSIONS: Possible PET scanning predictors of treatment response were identified in patients with major depression who had undergone anterior cingulotomy. Further research will be necessary to determine the reproducibility of this finding. If confirmed, the availability of an index for noninvasively predicting a patient's response to cingulotomy for the treatment of major depression would be of great clinical value.

Adult↗

Modulating limbic-cortical circuits in depression: targets of antidepressant treatments.

Of potential importance to the development and testing of novel and more effective antidepressant therapies is the noninvasive characterization of requisite brain changes mediating depression remission. A further clinical goal is the identification of pretreatment markers that might eventually inform optimal treatment selection. Toward these objectives, functional neuroimaging studies have described resting-state glucose metabolic and blood flow abnormalities in cortical, subcortical, and limbic regions, including changes with various antidepressant treatments. There is, however, variability in both site and direction of changes across published reports. In this article, a cortical-limbic network model of depression is used to explain this variability. In this approach, network dysfunction combined with ongoing intrinsic compensatory processes is seen to explain the heterogeneity of depressive symptoms observed clinically, as well as variations in pretreatment scan patterns. Furthermore, the synchronized modulation of these dysfunctional cortical-limbic pathways is considered critical for illness remission, regardless of treatment modality. Formal testing of disease-specific and response-specific functional interactions among regions in this depression network using multivariate approaches are discussed, with a perspective aimed at future studies examining treatment nonresponse, relapse risk, and disease vulnerability.

Affect↗

Unmasking disease-specific cerebral blood flow abnormalities: mood challenge in patients with remitted unipolar depression.

OBJECTIVE: Remitted major depressive disorder is a vulnerable clinical state, suggesting persistence of an underlying disease diathesis between episodes. To investigate neural correlates of such risk and to identify potential depression trait markers, euthymic unipolar patients in remission, acutely depressed patients, and never-depressed volunteers were studied before and after transient sad mood challenge. METHOD: Common and differential changes in regional blood flow among the groups relative to the baseline state were examined with [(15)O]H(2)O positron emission tomography after provocation of sadness with autobiographical memory scripts. RESULTS: Mood provocation in both depressed groups resulted in regional cerebral blood flow (rCBF) decreases in medial orbitofrontal cortex Brodmann's area 10/11, which were absent in the healthy group. In the remitted group, mood provocation produced a unique rCBF decrease in pregenual anterior cingulate 24a. The main effects in healthy subjects, an rCBF increase in subgenual cingulate Brodmann's area 25 and a decrease in right prefrontal cortex Brodmann's area 9, were not present in the depressed groups. CONCLUSIONS: Mood challenge in unipolar euthymic patients in full remission unmasks an apparent depression trait marker. The pattern of acute CBF changes is distinct from that seen in euthymic healthy volunteers and mirrors the untreated depressed state seen during a major depressive episode and the pattern of change seen in depressed patients. These findings suggest that disease-specific modifications of pathways mediating transient mood changes are present in unipolar depression independent of clinical illness status. These findings have implications for understanding the vulnerability of remitted patients for illness relapse.

Adult↗