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Background Transcranial focused ultrasound (tFUS) is a noninvasive brain stimulation method that may modulate deep brain structures. This study investigates whether sonication of the right anterior thalamus would modulate thermal pain thresholds in healthy individuals. Methods We enrolled 19 healthy individuals in this three-visit, double-blind, sham-controlled, crossover trial. Participants first underwent a structural MRI scan used solely for tFUS targeting. They then attended two identical experimental tFUS visits (counterbalanced by condition) at least one week apart. Within the MRI scanner, participants received two, 10-min sessions of either active or sham tFUS spread 10 min apart targeting the right anterior thalamus [fundamental frequency: 650 kHz, Pulse repetition frequency: 10 Hz, Pulse Width: 5 ms, Duty Cycle: 5%, Sonication Duration: 30s, Inter-Sonication Interval: 30 s, Number of Sonications: 10, ISPTA.0 995 mW/cm2, ISPTA.3 719 mW/cm2, Peak rarefactional pressure 0.72 MPa]. The primary outcome measure was quantitative sensory thresholding (QST), measuring sensory, pain, and tolerance thresholds to a thermal stimulus applied to the left forearm before and after right anterior thalamic tFUS. Results The right anterior thalamus was accurately sonicated in 17 of the 19 subjects. Thermal pain sensitivity was significantly attenuated after active tFUS. The pre-post x active-sham interaction was significant (F(1,245.95) = 4.03, p = .046). This interaction indicates that in the sham stimulation condition, thermal pain thresholds decreased 1.08 °C (SE = 0.28) pre-post session, but only decreased .51 °C (SE = 0.30) pre-post session in the active stimulation group. Conclusions Two 10-min sessions of anterior thalamic tFUS induces antinociceptive effects in healthy individuals. Future studies should optimize the parameter space, dose and duration of this effect which may lead to multi-session tFUS interventions for pain disorders.

Surgical techniques targeting behavioral disorders date back thousands of years. In this review, the authors discuss the history of neurosurgery for psychiatric disorders, starting with trephination in the Stone Age, progressing through the fraught practice of prefrontal lobotomy, and ending with modern neurosurgical techniques for treating psychiatric conditions, including ablative procedures, conventional deep brain stimulation, and closed-loop neurostimulation. Despite a tumultuous past, psychiatric neurosurgery is on the cusp of becoming a transformative therapy for patients with psychiatric dysfunction, with an ever-increasing evidence base suggesting reproducible and ethical therapeutic benefit.

Background Repetitive transcranial magnetic stimulation (rTMS) was approved in 2008 in the United States, and there are relatively few studies describing its use in regular clinical practice since approval. Methods From April 2011 to October 2014, ten sites within the National Network of Depression Centers (NNDC) provided data on 62 evaluable patients with a depressive episode. Treatment was determined naturalistically. Response was assessed by the Quick Inventory of Depressive Symptoms, Self-Report (QIDS-SR) as the primary outcome, and the Patient Health Questionnaire-9 (PHQ-9) and the clinician-rated Clinical Global Impression (CGI) as secondary depression measures. Results Enrolled patients exhibited significant treatment resistance, with 70.2% reporting more than 4 prior depressive episodes. Most patients received treatment with standard parameters (10 Hz over the left dorsolateral prefrontal cortex), although 22.6% of the patients received 1 or 5 Hz stimulation at some point. Over 6 weeks of treatment, response and remission rates were 29.4% and 5.9%, respectively, for the QIDS-SR; 39.2% and 15.7%, respectively, for the PHQ-9; and 50.9% and 17.9%, respectively, for the CGI. Moderator analyses revealed no effect of prior depressive episodes, history of ECT or gender, although early life stress predicted a better response to rTMS therapy. Limitations The study was an open-label, registry trial, with relatively coarse clinical data, reflecting practice only in academic, depression-specialty centers. Because of the relatively small size and heterogeneity of the sample, type 2 errors are possible and positive findings are in need of replication. Conclusion rTMS demonstrates effectiveness in clinical practice within the NNDC, although remission rates appear slightly lower in comparison with other recent naturalistic studies.

Objective Electroconvulsive therapy (ECT) is the most rapid and effective antidepressant treatment but with concerns about cognitive adverse effects. A new form of ECT, focal electrically administered seizure therapy (FEAST), was designed to increase the focality of stimulation and better match stimulus parameters with neurophysiology. We recently reported on the safety and feasibility of FEAST in a cohort (n = 17) of depressed patients. We now report on the safety, feasibility, preliminary efficacy, and cognitive effects of FEAST in a new cohort. Methods Open-label FEAST was administered to 20 depressed adults (6 men; 3 with bipolar disorder; age 49.1 ± 10.6 years). Clinical and cognitive assessments were obtained at baseline and end of course. Time to orientation recovery was assessed at each treatment. Nonresponders switched to conventional ECT. Results Participants tolerated the treatment well with no dropouts. Five patients (25%) transitioned from FEAST to conventional ECT due to inadequate response. After FEAST (mean, 9.3 ± 3.5 sessions; range, 4–14), there was a 58.1% ± 36.0% improvement in Hamilton Rating Scale for Depression scores compared with that in the baseline (P < 0.0001); 13 (65%) of 20 patients met response criteria, and 11 (55%) of 20 met remission criteria. Patients achieved reorientation (4 of 5 items) in 4.4 ± 3.0 minutes (median, 4.5 minutes), timed from eyes opening. There was no deterioration in neuropsychological measures. Conclusions These findings provide further support for the safety and efficacy of FEAST. The remission and response rates were in the range found using conventional ECT, and the time to reorientation may be quicker. However, without a randomized comparison group, conclusions are tentative.

Previous studies have demonstrated that combined total sleep deprivation (Wake therapy), sleep phase advance, and bright light therapy (Triple Chronotherapy) produce a rapid and sustained antidepressant effect in acutely depressed individuals. To date no studies have explored the impact of the intervention on unipolar depressed individuals with acute concurrent suicidality. Participants were suicidal inpatients (N = 10, Mean age = 44 ± 16.4 SD, 6F) with unipolar depression. In addition to standard of care, they received open label Triple Chronotherapy. Participants underwent one night of total sleep deprivation (33-36 h), followed by a three-night sleep phase advance along with four 30-min sessions of bright light therapy (10,000 lux) each morning. Primary outcome measures included the 17 item Hamilton depression scale (HAM17), and the Columbia Suicide Severity Rating Scale (CSSRS), which were recorded at baseline prior to total sleep deprivation, and at protocol completion on day five. Both HAM17, and CSSRS scores were greatly reduced at the conclusion of the protocol. HAM17 scores dropped from a mean of 24.7 ± 4.2 SD at baseline to a mean of 9.4 ± 7.3 SD on day five (p = .002) with six of the ten individuals meeting criteria for remission. CSSRS scores dropped from a mean of 19.5 ± 8.5 SD at baseline to a mean of 7.2 ± 5.5 SD on day five (p = .01). The results of this small pilot trial demonstrate that adjunctive Triple Chronotherapy is feasible and tolerable in acutely suicidal and depressed inpatients. Limitations include a small number of participants, an open label design, and the lack of a comparison group. Randomized controlled studies are needed.

The use of brain stimulation for the treatment and investigation of mood disorders is rapidly expanding. Mood disorders are common, but so are treatment-refractory or intolerant patients, explaining increasing interest in alternatives to medications and talk therapy. Additionally, depressive episodes are periodic or temporary states and are thus amenable to pulsatile, non-systemic treatments. The oldest brain stimulation method, electroconvulsive therapy (ECT), remains the most effective acute antidepressant available. The newer brain stimulation methods, in particular repetitive transcranial magnetic stimulation (rTMS), also show that non-invasive stimulation of key brain regions not only effectively treats depression, but also causes quantifiable changes in brain biomarkers. More research is needed, though, to better understand how these treatments work, for whom they work, and how to optimize their use.

Background Epidural prefrontal cortical stimulation (EpCS) represents a novel therapeutic approach with many unique benefits that can be used for treatment-resistant depression (TRD). Objective To examine the long-term safety and efficacy of EpCS of the frontopolar cortex (FPC) and dorsolateral prefrontal cortex (DLPFC) for treatment of TRD. Methods Adults ( N = 5) who were 21–80 years old with severe TRD [failure to respond to adequate courses of at least 4 antidepressant medications, psychotherapy and ≥20 on the Hamilton Rating Scale for Depression (HRSD24)] were recruited. Participants were implanted with bilateral EpCS over the FPC and DLPFC and received constant, chronic stimulation throughout the five years with Medtronic IPGs. They were followed for 5 years (2/1/2008–10/14/2013). Efficacy of EpCS was assessed with the HRSD24 in an open-label design as the primary outcome measure at five years. Results All 5 patients continued to tolerate the therapy. The mean improvements from pre-implant baseline on the HRSD24 were [7 months] 54.9% (±37.7), [1 year] 41.2% (±36.6), [2 years] 53.8% (±21.7), and [5 years] 45% (±47). Three of 5 (60%) subjects continued to be in remission at 5 years. There were 5 serious adverse events: 1 electrode ‘paddle’ infection and 4 device malfunctions, all resulting in suicidal ideation and/or hospitalization. Conclusion These results suggest that chronic bilateral EpCS over the FPC and DLPFC is a promising and potentially durable new technology for treating TRD, both acutely and over 5 years.

Objective: To systematically review the literature to date applying repetitive transcranial magnetic stimulation (rTMS) or transcranial direct current stimulation (tDCS) for patients with fibromyalgia syndrome (FMS). Method: Electronic bibliography databases screened included PubMed, Ovid MEDLINE, PsychINFO, CINAHL, and Cochrane Library. The keyword “fibromyalgia” was combined with (“transcranial” and “stimulation”) or “TMS” or “tDCS” or “transcranial magnetic stimulation” or “transcranial direct current stimulation”. Results: Nine of 23 studies were included; brain stimulation sites comprised either the primary motor cortex (M1) or the dorsolateral prefrontal cortex (DLPFC). Five studies used rTMS (high-frequency-M1: 2, low-frequency-DLPFC: 2, high-frequency-DLPFC: 1), while 4 applied tDCS (anodal-M1: 1, anodal-M1/DLPFC: 3). Eight were double-blinded, randomized controlled trials. Most (80%) rTMS studies that measured pain reported significant decreases, while all (100%) tDCS studies with pain measures reported significant decreases. Greater longevity of significant pain reductions was observed for excitatory M1 rTMS/tDCS. Conclusion: Studies involving excitatory rTMS/tDCS at M1 showed analogous pain reductions as well as considerably fewer side effects compared to FDA apaproved FMS pharmaceuticals. The most commonly reported side effects were mild, including transient headaches and scalp discomforts at the stimulation site. Yearly use of rTMS/tDCS regimens appears costly ($11,740 to 14,507/year); however, analyses to apapropriately weigh these costs against clinical and quality of life benefits for patients with FMS are lacking. Consequently, rTMS/tDCS should be considered when treating patients with FMS, particularly those who are unable to find adequate symptom relief with other therapies. Further work into optimal stimulation parameters and standardized outcome measures is needed to clarify associated efficacy and effectiveness.

A 59-year-old Caucasian man with a past history of Parkinson's disease (PD) status post-bilateral subthalamic nucleus (STN) deep brain stimulation (DBS), who also had treatment-resistant (TR) obsessive-compulsive disorder (OCD), and treatment-resistant depression (TRD), presented for further evaluation and management of his TR OCD. After an unsuccessful attempt to treat his OCD by reprogramming his existing STN DBS, he was offered bilateral ventral capsule/ventral striatum (VC/VS) DBS surgery. In addition to the expected improvement in OCD symptoms, he experienced significant improvement in both PD-related apathy and depression along with resolution of suicidal ideation. Furthermore, the patient's festinating gait dramatically improved. This case demonstrates that DBS of both the STN and VC/VS appears to have an initial signal of safety and tolerability. This is the first instance where both the STN and the VC/VS DBS targets have been implanted in an individual and the first case where a patient with PD has received additional DBS in mood-regulatory circuitry.

Interventional psychiatry offers substantial therapeutic benefits in some neuropsychiatric disorders and enormous potential in treating others. However, as interventional diagnostics and therapeutics require specialized knowledge and skill foreign to many psychiatrists, the emerging subspecialty of interventional psychiatry must be more formally integrated into the continuum of psychiatric training to ensure both safe application and continued growth. By establishing training paradigms for interventional psychiatry, academic medical centers can help fill this knowledge gap. The cultivation of a properly trained cohort of interventional psychiatrists will better meet the challenges of treatment-resistant psychiatric illness through safe and ethical practice, while facilitating a more informed development and integration of novel neuromodulation techniques.

Meditation involves attentional regulation and may lead to increased activity in brain regions associated with attention such as dorsal lateral prefrontal cortex (DLPFC) and anterior cingulate cortex (ACC). Using functional magnetic resonance imaging, we examined whether DLPFC and ACC were activated during meditation. Subjects who meditate were recruited and scanned on a 3.0 Tesla scanner. Subjects meditated for four sessions of 12 min and performed four sessions of a 6 min control task. Individual and group t-maps were generated of overall meditation response versus control response and late meditation response versus early meditation response for each subject and time courses were plotted. For the overall group (n= 13), and using an overall brain analysis, there were no statistically significant regional activations of interest using conservative thresholds. A region of interest analysis of the entire group time courses of DLPFC and ACC were statistically more active throughout meditation in comparison to the control task. Moreover, dividing the cohort into short (n= 8) and long-term (n= 5) practitioners (>10 years) revealed that the time courses of long-term practitioners had significantly more consistent and sustained activation in the DLPFC and the ACC during meditation versus control in comparison to short-term practitioners. The regional brain activations in the more practised subjects may correlate with better sustained attention and attentional error monitoring. In summary, brain regions associated with attention vary over the time of a meditation session and may differ between long- and short-term meditation practitioners.

This case report describes the history and hospital course of an otherwise healthy 20-year-old male with bipolar I disorder who developed symptoms of severe lithium toxicity, culminating in a seizure, despite a level of lithium of only 0.8 mEq/L, within the usual therapeutic range. The discussion emphasizes that lithium toxicity is diagnosed by clinical symptoms and can occur even at usual therapeutic blood levels.

Vagus nerve stimulation is an interesting new approach to treating neuropsychiatric diseases within the class of brain-stimulation devices sometimes labeled 'neuromodulators'. With vagus nerve stimulation, a battery-powered generator implanted in the chest wall connects to a wire wrapped around the vagus nerve in the neck, and sends intermittent pulses of electricity along the nerve directly into the brain. This mechanism takes advantage of the natural role of the vagus nerve in conveying information into the brain concerning homeostatic information (e.g., hunger, chest pain and respirations). Vagus nerve stimulation therapy is US FDA approved for the adjunctive treatment of epilepsy and has recently been FDA approved for the treatment of medication-resistant depression. Owing to its novel route into the brain, it has no drug-drug interactions or systemic side effects. This treatment also appears to have high long-term tolerability in patients, with low rates of patients relapsing on vagus nerve stimulation or becoming tolerant. However, alongside the excitement and enthusiasm for this new treatment, a lack of Class I evidence of efficacy in treating depression is currently slowing down adoption by psychiatrists. Much more research is needed regarding exactly how to refine and deliver the electrical pulses and how this differentially affects brain function in health and disease.

Objective The purpose of this study is to determine whether patients with a discharge diagnosis of bipolar depression were prescribed medications that are in accordance with evidence-based treatment guidelines and are FDA-approved for bipolar depression. Methods A retrospective study was conducted to assess prescribing of evidence-based therapies for patients discharged between November 2007 and August 2010 with a diagnosis code of BPD at the time of discharge. The primary objective of the study was to determine if evidence-based medications were prescribed at the time of discharge. Secondary objectives included analysis of other medications used, concomitant disease states and drug therapy, rate of readmission, and rate of therapeutic drug monitoring. Results Of 294 patients, 170 (58%) were prescribed evidence-based medications upon discharge. The most commonly used medication was quetiapine. The most commonly prescribed off-label medications were atypical antipsychotics. For patients on antipsychotics, rates of appropriate monitoring were variable. Seventy percent of patients receiving lithium had a therapeutic concentration prior to discharge. Differences in rates of readmission between groups were not significant. Conclusions Rates of prescribing evidence-based medications at discharge for patients with BPD were low. Additionally, evidence-based monitoring for specific medications was variable. Future studies reviewing treatment course and illness severity may provide more information about appropriate medication use in patients with BPD.

To the Editor: Twenty-five to 30% of patients with schizophrenia report persistent auditory hallucinations despite an adequate treatment regimen.1 Transcranial direct-current stimulation (tDCS) is a noninvasive method that modulates cortical excitability through electrodes placed directly on the scalp. Anode stimulation subthreshold depolarizes neuronal membranes, while cathode stimulation subthreshold hyperpolarizes neurons.2 The tDCS method has been used to treat major depressive disorder. In patients with major depressive disorder, functional magnetic resonance imaging has shown prefrontal asymmetry with hypoactivity of the left dorsolateral prefrontal cortex (DLPFC) and hyperactivity of the right DLPFC.3 Placement of the anode (excitatory) over the left DLPFC and the cathode (inhibitory) over the right DLPFC is theorized to correct the abnormal frontal activity. Using this model of neuromodulation, it can be hypothesized that similar strategies could be used to target imbalances of neuronal activity in patients experiencing auditory hallucinations. Studies with functional magnetic resonance imaging have shown that hypoactivity in the left prefrontal cortex and left anterior cingulate is associated with auditory hallucinations in patients with schizophrenia.4 Brunelin et al1 showed that tDCS significantly reduced persistent auditory hallucinations in refractory psychosis. Additionally, the effects of tDCS appear to be multifactorial, as it stimulates both local and remote plastic changes mediated by regulation of neurotransmitters including dopamine, acetylcholine, and serotonin.5 We describe a patient who was not responding to treatment with clozapine and ECT and ultimately derived benefit from the addition of tDCS. Case report. Mr A is a 53-year-old man with a 30-year history of schizoaffective disorder, depressed type (per DSM-IV criteria), who suffers from persistent auditory hallucinations. He received an acute course of electroconvulsive therapy (ECT) with maintenance weekly ECT treatments for several months and clozapine 700 mg daily, yet continued to psychiatrically decompensate. Time between weekly ECT treatments could not be lengthened due to worsening auditory hallucinations, leading him to become suicidal and subsequently hospitalized. Mr A was given tDCS adjunctively, and his progress was monitored using the Positive and Negative Syndrome Scale (PANSS), with baseline assessment recorded before treatment initiation and reassessment recorded 1 day posttreatment before subsequent initiation of ECT. Weekly ECT treatments were held during tDCS administration and restarted the following week. Mr A was given the standard regimen of 20-minute tDCS treatments twice daily for 5 consecutive days. The stimulator was set to deliver 2 milliamps with anodal (excitatory) stimulation placed over the left DLPFC and cathodal (inhibitory) stimulation placed over the left temporoparietal cortex. Mr A’s pretreatment PANSS score for positive symptoms was 13 and remained the same posttreatment, but showed a 67% improvement in delusions and a 20% improvement in auditory hallucinations. The negative symptom pretreatment PANSS score of 22 remained static posttreatment; however, blunted affect decreased by 20% and emotional withdrawal decreased by 40%. The general psychopathology pretreatment PANSS score demonstrated overall improvement of 22%, with a 33% decrease in anxiety, 20% decrease in depression, 67% decrease in lack of judgment/insight, and 50% decrease in guilt, tension, and uncooperativeness. Overall, Mr A reported improved mood, feelings of hope, and fewer auditory hallucinations. Discussion. The addition of tDCS, as an adjunctive treatment to ECT and clozapine, provided a beneficial response in Mr A. This case shows a patient who experienced near immediate improvement in positive symptoms of auditory hallucinations, which is consistent with the findings published by Brunelin et al,1 who found tDCS reduces auditory hallucinations refractory to antipsychotic drugs in patients with schizophrenia. This case suggests that tDCS may help reduce severe auditory hallucinations as well as negative symptoms when used in combination with ECT and antipsychotic treatment. The patient presented here demonstrates an overall positive response with the addition of tDCS to his treatment regimen. Further study is warranted to ascertain whether tDCS may be an effective adjunct to ECT and pharmacotherapy in treatment-resistant hallucinations.

Interventional psychiatry is an emerging subspecialty that uses a variety of procedural neuromodulation techniques in the context of an electrocircuit-based view of mental dysfunction as proximal causes for psychiatric diseases.The authors propose the development of an interventional psychiatry-training paradigm analogous to those found in cardiology and neurology.The proposed comprehensive training in interventional psychiatry would include didactics in the theory, proposed mechanisms, and delivery of invasive and noninvasive brain stimulation.The development and refinement of this subspecialty would facilitate safe, effective growth in the field of brain stimulation by certified and credentialed practitioners within the field of psychiatry while also potentially improving the efficacy of current treatments.

Daily left prefrontal transcranial magnetic stimulation (TMS) for several weeks was first proposed as an acute treatment for depression in the early 1990s, and was Food and Drug Administration (FDA) approved in 2008. In the past year, several important studies have been published that extend our understanding of this novel treatment approach.The first round of multisite clinical trials with TMS addressed whether prefrontal rTMS has efficacy and were conducted in carefully selected depressed patients who were antidepressant medication free. Several more recent studies assess the clinical effectiveness of TMS and report that about 35-40% of real-world patients who are commonly taking adjunctive antidepressants reach remission with a modest side effect profile. There are also new studies examining the durability of the TMS-induced antidepressant effect. Fifty-eight percent of TMS remitters remain remitted at 3-month follow-up.These recent studies suggest that daily left prefrontal TMS over several weeks as a treatment for depression not only appears to have efficacy in rigorous randomized controlled trials, but is effective in real-world settings, with remission in 30-40% of patients. The TMS antidepressant effect, once achieved, appears to be as durable as with other antidepressant medications or interventions. Much more research is needed, particularly with issues such as the TMS coil location, stimulation intensity and frequency, and dosing strategy.

Transcranial magnetic stimulation (TMS) of the prefrontal cortex can cause changes in acute pain perception. Several weeks of daily left prefrontal TMS has been shown to treat depression. We recruited 20 patients with fibromyalgia, defined by American College of Rheumatology criteria, and randomized them to receive 4000 pulses at 10 Hz TMS (n=10), or sham TMS (n=10) treatment for 10 sessions over 2 weeks along with their standard medications, which were fixed and stable for at least 4 weeks before starting sessions. Subjects recorded daily pain, mood, and activity. Blinded raters assessed pain, mood, functional status, and tender points weekly with the Brief Pain Inventory, Hamilton Depression Rating Scale, and Fibromyalgia Impact Questionnaire. No statistically significant differences between groups were observed. Patients who received active TMS had a mean 29% (statistically significant) reduction in pain symptoms in comparison to their baseline pain. Sham TMS participants had a 4% nonsignificant change in daily pain from their baseline pain. At 2 weeks after treatment, there was a significant improvement in depression symptoms in the active group compared to baseline. Pain reduction preceded antidepressant effects. TMS was well tolerated, with few side effects. Further studies that address study limitations are needed to determine whether daily prefrontal TMS may be an effective, durable, and clinically useful treatment for fibromyalgia symptoms.

Purpose of reviewThere has been a resurgence of interest in brain stimulationtechniques as therapies for psychiatric disorders. Variousnames are used for this class of treatments:neuromodulation, somatic therapies, brain stimulationtechniques. The methods in this class range from non-invasive (transcranial magnetic stimulation) to invasive brainsurgery (deep brain stimulation).Recent findingsWithin the past year, the results of several large multicentertrials have been published, clearing the way for US Foodand Drug Administration approval of vagus nervestimulation for recurrent treatment-resistant depression anda pending consideration of approving transcranial magneticstimulation for the treatment of depression.SummaryThis article reviews the most important recent clinicallyrelevant manuscripts in this rapidly expanding new field.Keywordsanticonvulsant, antidepressant, deep brain stimulation,electroconvulsive therapy, transcranial magneticstimulation, vagus nerve stimulation

Deep brain stimulation(DBS) is emerging as a pow-erful tool for the alleviation of targeted symptoms in treatment-resistant neuropsychiatric disorders. Despite the expanding use of neuropsychiatric DBS, the mecha-nisms responsible for its effects are only starting to be elucidated. Several modalities such as quantitative elec-troencephalography as well a intraoperative recordings have been utilized to attempt to understand the under-pinnings of this new treatment modality, but functional imaging appears to offer several unique advantages. Functional imaging techniques like positron emission tomography, single photon emission computed tomog-raphy and functional magnetic resonance imaging have been used to examine the effects of focal DBS on activ-ity in a distributed neural network. These investigations are critical for advancing the field of invasive neuro-modulation in a safe and effective manner, particularly in terms of defining the neuroanatomical targets and refining the stimulation protocols. The purpose of this review is to summarize the current functional neuroim-aging findings from neuropsychiatric DBS implantation for three disorders: treatment-resistant depression, obsessive-compulsive disorder, and Tourette syndrome. All of the major targets will be discussed(Nucleus ac-cumbens, anterior limb of internal capsule, subcallosal cingulate, Subthalamic nucleus, Centromedial nucleus of the thalamus-Parafasicular complex, frontal pole, and dorsolateral prefrontal cortex). We will also address some apparent inconsistencies within this literature, and suggest potential future directions for this promis-ing area.