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153 result(s) for "Rauch, Scott L"
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Invasive Circuitry-Based Neurotherapeutics: Stereotactic Ablation and Deep Brain Stimulation for OCD
Psychiatric neurosurgery, specifically stereotactic ablation, has continued since the 1940s, mainly at a few centers in Europe and the US. Since the late 1990s, the resurgence of interest in this field has been remarkable; reports of both lesion procedures and the newer technique of deep brain stimulation (DBS) have increased rapidly. In early 2009, the US FDA granted limited humanitarian approval for DBS for otherwise intractable obsessive-compulsive disorder (OCD), the first such approval for a psychiatric illness. Several factors explain the emergence of DBS and continued small-scale use of refined lesion procedures. DBS and stereotactic ablation have been successful and widely used for movement disorders. There remains an unmet clinical need: current drug and behavioral treatments offer limited benefit to some seriously ill people. Understandings of the neurocircuitry underlying psychopathology and the response to treatment, while still works in progress, are much enhanced. Here, we review modern lesion procedures and DBS for OCD in the context of neurocircuitry. A key issue is that clinical benefit can be obtained after surgeries targeting different brain structures. This fits well with anatomical models, in which circuits connecting orbitofrontal cortex (OFC), medial prefrontal cortex (mPFC), basal ganglia, and thalamus are central to OCD pathophysiology and treatment response. As in movement disorders, dedicated interdisciplinary teams, here led by psychiatrists, are required to implement these procedures and maintain care for patients so treated. Available data, although limited, support the promise of stereotactic ablation or DBS in carefully selected patients. Benefit in such cases appears not to be confined to obsessions and compulsions, but includes changes in affective state. Caution is imperative, and key issues in long-term management of psychiatric neurosurgery patients deserve focused attention. DBS and contemporary ablation also present different patterns of potential benefits and burdens. Translational research to elucidate how targeting specific nodes in putative OCD circuitry might lead to therapeutic gains is accelerating in tandem with clinical use.
PERIL AND PLEASURE: AN RDOC-INSPIRED EXAMINATION OF THREAT RESPONSES AND REWARD PROCESSING IN ANXIETY AND DEPRESSION
As a step toward addressing limitations in the current psychiatric diagnostic system, the National Institute of Mental Health recently developed the Research Domain Criteria (RDoC) to stimulate integrative research—spanning self‐report, behavior, neural circuitry, and molecular/genetic mechanisms—on core psychological processes implicated in mental illness. Here, we use the RDoC conceptualization to review research on threat responses, reward processing, and their interaction. The first section of the manuscript highlights the pivotal role of exaggerated threat responses—mediated by circuits connecting the frontal cortex, amygdala, and midbrain—in anxiety, and reviews data indicating that genotypic variation in the serotonin system is associated with hyperactivity in this circuitry, which elevates the risk for anxiety and mood disorders. In the second section, we describe mounting evidence linking anhedonic behavior to deficits in psychological functions that rely heavily on dopamine signaling, especially cost/benefit decision making and reward learning. The third section covers recent studies that document negative effects of acute threats and chronic stress on reward responses in humans. The mechanisms underlying such effects are unclear, but the fourth section reviews new optogenetic data in rodents indicating that GABAergic inhibition of midbrain dopamine neurons, driven by activation of the habenula, may play a fundamental role in stress‐induced anhedonia. In addition to its basic scientific value, a better understanding of interactions between the neural systems that mediate threat and reward responses may offer relief from the burdensome condition of anxious depression.
An Ethics Checklist for Digital Health Research in Psychiatry: Viewpoint
Psychiatry has long needed a better and more scalable way to capture the dynamics of behavior and its disturbances, quantitatively across multiple data channels, at high temporal resolution in real time. By combining 24/7 data-on location, movement, email and text communications, and social media-with brain scans, genetics, genomics, neuropsychological batteries, and clinical interviews, researchers will have an unprecedented amount of objective, individual-level data. Analyzing these data with ever-evolving artificial intelligence could one day include bringing interventions to patients where they are in the real world in a convenient, efficient, effective, and timely way. Yet, the road to this innovative future is fraught with ethical dilemmas as well as ethical, legal, and social implications (ELSI). The goal of the Ethics Checklist is to promote careful design and execution of research. It is not meant to mandate particular research designs; indeed, at this early stage and without consensus guidance, there are a range of reasonable choices researchers may make. However, the checklist is meant to make those ethical choices explicit, and to require researchers to give reasons for their decisions related to ELSI issues. The Ethics Checklist is primarily focused on procedural safeguards, such as consulting with experts outside the research group and documenting standard operating procedures for clearly actionable data (eg, expressed suicidality) within written research protocols. We explored the ELSI of digital health research in psychiatry, with a particular focus on what we label \"deep phenotyping\" psychiatric research, which combines the potential for virtually boundless data collection and increasingly sophisticated techniques to analyze those data. We convened an interdisciplinary expert stakeholder workshop in May 2020, and this checklist emerges out of that dialogue. Consistent with recent ELSI analyses, we find that existing ethical guidance and legal regulations are not sufficient for deep phenotyping research in psychiatry. At present, there are regulatory gaps, inconsistencies across research teams in ethics protocols, and a lack of consensus among institutional review boards on when and how deep phenotyping research should proceed. We thus developed a new instrument, an Ethics Checklist for Digital Health Research in Psychiatry (\"the Ethics Checklist\"). The Ethics Checklist is composed of 20 key questions, subdivided into 6 interrelated domains: (1) informed consent; (2) equity, diversity, and access; (3) privacy and partnerships; (4) regulation and law; (5) return of results; and (6) duty to warn and duty to report. Deep phenotyping research offers a vision for vastly more effective care for people with, or at risk for, psychiatric disease. The potential perils en route to realizing this vision are significant; however, and researchers must be willing to address the questions in the Ethics Checklist before embarking on each leg of the journey.
Pre-treatment amygdala activation and habituation predict symptom change in post-traumatic stress disorder
Trauma-focused psychotherapy approaches are the first-line treatment option for post-traumatic stress disorder (PTSD); however, up to a third of patients remain symptomatic even after completion of the treatment. Predicting which patients will respond to a given treatment option would support personalized treatments and improve the efficiency of healthcare systems. Although previous neuroimaging studies have examined possible pre-treatment predictors of response to treatment, the findings have been somewhat inconsistent, and no other study has examined habituation to stimuli as a predictor. In this study, 16 treatment-seeking adults (M Age = 43.63, n = 10 women) with a primary diagnosis of PTSD passively viewed pictures of emotional facial expressions during functional magnetic resonance imaging (fMRI). After scanning, participants rated facial expressions on both valence and arousal. Participants then completed eight weekly sessions of prolonged exposure (PE) therapy. PTSD symptom severity was measured before and after treatment. Overall, participants showed symptomatic improvement with PE. Consistent with hypotheses, lesser activation in the amygdala and greater activation in the ventromedial prefrontal cortex during the presentation of fearful vs. happy facial expressions, as well as a greater decline in amygdala activation across blocks of fearful facial expressions at baseline, were associated with greater reduction of PTSD symptoms. Given that the repeated presentation of emotional material underlies PE, changes in brain responses with repeated stimulus presentations warrant further studies as potential predictors of response to exposure therapies.
Dorsal Anterior Cingulate Thickness Is Related to Alexithymia in Childhood Trauma-Related PTSD
Alexithymia, or \"no words for feelings\", is highly prevalent in samples with childhood maltreatment and posttraumatic stress disorder (PTSD). The dorsal anterior cingulate cortex (dACC) has been identified as a key region involved in alexithymia, early life trauma, and PTSD. Functional alterations in the dACC also have been associated with alexithymia in PTSD. This study examined whether dACC morphology is a neural correlate of alexithymia in child maltreatment-related PTSD. Sixteen adults with PTSD and a history of childhood sexual abuse, physical abuse, or exposure to domestic violence, and 24 healthy controls (HC) completed the Toronto Alexithymia Scale 20 (TAS-20) and underwent magnetic resonance imaging. Cortical thickness of the dACC was measured using FreeSurfer, and values were correlated with TAS-20 scores, controlling for sex and age, in both groups. Average TAS-20 score was significantly higher in the PTSD than the HC group. TAS-20 scores were significantly positively associated with dACC thickness only in the PTSD group. This association was strongest in the left hemisphere and for TAS-20 subscales that assess difficulty identifying and describing feelings. We found that increasing dACC gray matter thickness is a neural correlate of greater alexithymia in the context of PTSD with childhood maltreatment. While findings are correlational, they motivate further inquiry into the relationships between childhood adversity, emotional awareness and expression, and dACC morphologic development in trauma-related psychopathology.
Thickness of Ventromedial Prefrontal Cortex in Humans Is Correlated with Extinction Memory
The ventromedial prefrontal cortex (vmPFC) has been implicated in fear extinction [Phelps, E. A., Delgado, M. R., Nearing, K. I. & Ledoux, J. E. (2004) Neuron 43, 897-905; Herry, C. & Garcia, R. (2003) Behav. Brain Res. 146, 89-96]. Here, we test the hypothesis that the cortical thickness of vmPFC regions is associated with how well healthy humans retain their extinction memory a day after having been conditioned and then extinguished. Fourteen participants underwent a 2-day fear conditioning and extinction protocol. The conditioned stimuli (CSs) were pictures of virtual lights, and the unconditioned stimulus (US) was an electric shock. On day 1, participants received 5 CS+US pairings (conditioning), followed by 10 CS trials with no US (extinction). On day 2, the CS was presented alone to test for extinction memory. Skin conductance response (SCR) was the behavioral index of conditioning and extinction. Participants underwent MRI scans to obtain structural images, from which cortical thickness was measured. We performed a vertex-based analysis across the entire cortical surface and a region-of-interest analysis of a priori hypothesized territories to measure cortical thickness and map correlations between this measure and SCR. We found significant, direct correlation between thickness of the vmPFC, specifically medial orbitofrontal cortex, and extinction retention. That is, thicker medial orbitofrontal cortex was associated with lower SCR to the conditioned stimulus during extinction recall (i.e., greater extinction memory). These results suggest that the size of the vmPFC might explain individual differences in the ability to modulate fear among humans.
Obsessive–compulsive disorder: an integrative genetic and neurobiological perspective
Key Points Obsessive–compulsive disorder (OCD) is a phenotypically complex multidimensional neuropsychiatric disorder. Family and twin studies provide definitive evidence that genetic and environmental factors can increase risk of the disorder. Candidate gene and genome-wide association studies provide strong suggestive evidence that genes in the serotonergic, dopaminergic and glutamatergic systems confer risk for the manifestation of OCD. Imaging studies as well as neuropsychological and treatment studies have implicated frontal–subcortical circuits in the pathophysiology of OCD. A cortico–striato–thalamo–cortical circuit is the prevailing model regarding the neural and pathophysiological underpinnings of OCD. The prevailing treatments include both pharmacological agents (selective serotonin-reuptake inhibitors) and cognitive behavioural therapy (CBT), with CBT and/or a combination of pharmacological and CBT being the most efficacious. Animal studies provide strong evidence for the involvement of the glutamatergic system in the expression of OCD-like behaviours. A model incorporating both genetic and epigenetic mechanisms in the manifestation of OCD is suggested as a heuristic for the pathophysiology of OCD. Obsessive–compulsive disorder has been scrutinized in many genetic, neuropsychological and neuroimaging studies. Pauls and colleagues provide an overview of our current understanding of the vulnerability factors, triggers and mechanisms underlying this devastating condition. Obsessive–compulsive disorder (OCD) is characterized by repetitive thoughts and behaviours that are experienced as unwanted. Family and twin studies have demonstrated that OCD is a multifactorial familial condition that involves both polygenic and environmental risk factors. Neuroimaging studies have implicated the cortico–striato–thalamo–cortical circuit in the pathophysiology of the disorder, which is supported by the observation of specific neuropsychological impairments in patients with OCD, mainly in executive functions. Genetic studies indicate that genes affecting the serotonergic, dopaminergic and glutamatergic systems, and the interaction between them, play a crucial part in the functioning of this circuit. Environmental factors such as adverse perinatal events, psychological trauma and neurological trauma may modify the expression of risk genes and, hence, trigger the manifestation of obsessive–compulsive behaviours.
Internet‐based cognitive behavior therapy for major depressive disorder: A randomized controlled trial
Background Prior research has shown that the Sadness Program, a technician‐assisted Internet‐based cognitive behavioral therapy (iCBT) intervention developed in Australia, is effective for treating major depressive disorder (MDD). The current study aimed to expand this work by adapting the protocol for an American population and testing the Sadness Program with an attention control group. Methods In this parallel‐group, randomized controlled trial, adult MDD participants (18–45 years) were randomized to a 10‐week period of iCBT (n = 37) or monitored attention control (MAC; n = 40). Participants in the iCBT group completed six online therapy lessons, which included access to content summaries and homework assignments. During the 10‐week trial, iCBT and MAC participants logged into the web‐based system six times to complete self‐report symptom scales, and a nonclinician technician contacted participants weekly to provide encouragement and support. The primary outcome was the Hamilton Rating Scale for Depression (HRSD), and the secondary outcomes were the Patient Health Questionnaire‐9 and Kessler‐10. Results Intent‐to‐treat analyses revealed significantly greater reductions in depressive symptoms in iCBT compared with MAC participants, using both the self‐report measures and the clinician‐rated HRSD (d = −0.80). Importantly, iCBT participants also showed significantly higher rates of clinical response and remission. Exploratory analyses did not support illness severity as a moderator of treatment outcome. Conclusions The Sadness Program led to significant reductions in depression and distress symptoms. With its potential to be delivered in a scalable, cost‐efficient manner, iCBT is a promising strategy to enhance access to effective care.
INSULA AND ANTERIOR CINGULATE GABA LEVELS IN POSTTRAUMATIC STRESS DISORDER: PRELIMINARY FINDINGS USING MAGNETIC RESONANCE SPECTROSCOPY
Background Increased reactivity of the insular cortex and decreased activity of the dorsal anterior cingulate cortex (ACC) are seen in functional imaging studies of posttraumatic stress disorder (PTSD), and may partly explain the persistent fear and anxiety proneness that characterize the disorder. A possible neurochemical correlate is altered function of the inhibitory neurotransmitter gamma‐aminobutyric acid (GABA). We report results from what we believe is the first study applying proton magnetic resonance spectroscopy (1H‐MRS) to measure brain GABA in PTSD. Methods Thirteen adults with DSM‐IV PTSD and 13 matched healthy control subjects underwent single voxel 1H‐MRS at 4 Tesla. GABA was measured in the right anterior insula and dorsal ACC, using Mescher‐Garwood Point‐Resolved Echo Spectroscopy Sequence (MEGAPRESS) spectral editing. Subjects were interviewed with the Structured Clinical Interview for DSM‐IV and the Clinician Administered PTSD Scale, and also completed the State and Trait Anxiety Inventory. Results Insula GABA was significantly lower in PTSD subjects than in controls, and dorsal ACC GABA did not differ significantly between the groups. Insula GABA was not significantly associated with severity of PTSD symptoms. However, lower insula GABA was associated with significantly higher state and trait anxiety in the subject sample as a whole. Conclusions PTSD is associated with reduced GABA in the right anterior insula. This preliminary evidence of the 1H‐MRS GABA metabolite as a possible biomarker of PTSD encourages replication in larger samples and examination of relations with symptom dimensions. Future studies also should examine whether insula GABA is a marker of anxiety proneness, cutting across clinical diagnostic categories.