Time course of clinical change following neurofeedback.

Neurofeedback - learning to modulate brain function through real-time monitoring of current brain state - is both a powerful method to perturb and probe brain function and an exciting potential clinical tool. For neurofeedback effects to be useful clinically, they must persist. Here we examine the time course of symptom change following neurofeedback in two clinical populations, combining data from two ongoing neurofeedback studies. This analysis reveals a shared pattern of symptom change, in which symptoms continue to improve for weeks after neurofeedback. This time course has several implications for future neurofeedback studies. Most neurofeedback studies are not designed to test an intervention with this temporal pattern of response. We recommend that new studies incorporate regular follow-up of subjects for weeks or months after the intervention to ensure that the time point of greatest effect is sampled. Furthermore, this time course of continuing clinical change has implications for crossover designs, which may attribute long-term, ongoing effects of real neurofeedback to the control intervention that follows. Finally, interleaving neurofeedback sessions with assessments and examining when clinical improvement peaks may not be an appropriate approach to determine the optimal number of sessions for an application.

Long-term outcome in adults with obsessive-compulsive disorder.

BACKGROUND: Obsessive-compulsive disorder (OCD) is a chronic condition that often produces lifelong morbidity, but few studies have examined long-term outcome (greater than 5 years) in adult patients. Available studies suggest that 32-74% of adult OCD patients will experience clinical improvement over the long term. However, these studies were conducted before validated OCD rating scales were established and the development of evidence-based treatments for OCD. METHODS: We investigated the 10-20 year outcome of 83 of 165 eligible subjects previously enrolled after participation in placebo-controlled trials of serotonin reuptake inhibitor (SRI) medications for OCD. We examined the association between clinical characteristics at initial assessment and OCD symptom severity at follow-up. We hypothesized that primary OCD symptom dimension and initial response to pharmacotherapy with serotonin reuptake inhibitors would be associated with later symptom severity. RESULTS: Only 20% (17 of 83) of subjects had experienced a remission of their OCD symptoms at follow-up (Y-BOCS ≤ 8). Forty-nine percent (41 of 83) of subjects were still experiencing clinically significant OCD symptoms. Response to initial SRI pharmacotherapy was significantly associated with long-term outcome: 31% (13 of 42) of subjects who responded (CGI < 3) to initial SRI pharmacotherapy were remitted at follow-up, compared to 12% (3 of 25) of partial responders and none of the 16 subjects who had no response to initial SRI pharmacotherapy. We did not find a significant association between long-term clinical outcome and any of the OCD symptom dimensions. CONCLUSION: Despite the introduction and dissemination of several evidence-based treatments for OCD, most adult OCD patients do not achieve remission. Initial response to pharmacotherapy was strongly associated with long-term outcome.

Neurofeedback for obsessive compulsive disorder: A randomized, double-blind trial.

We aim to develop fMRI neurofeedback as a treatment for obsessive compulsive disorder (OCD). In prior work, we found that providing neurofeedback of activity in the anterior prefrontal cortex (aPFC) improved control over contamination anxiety in a subclinical population. Here, we present the results of a randomized, double-blind clinical trial (NCT02206945) testing this intervention in patients with OCD. We recruited patients with primary symptoms in the fear-of-harm/checking or contamination/washing domains. During neurofeedback, they viewed symptom provocative images and attempted to up- and down-regulate the aPFC during different blocks of time. The active group received two sessions of neurofeedback and the control group received yoked sham feedback. The primary outcome measure was the Yale-Brown Obsessive-Compulsive Symptom scale. The secondary outcome was control over aPFC. Thirty-six participants completed feedback training (18 active, 18 control). The active group had a slightly but significantly greater reduction of obsessive-compulsive symptoms after neurofeedback compared to the control group (p<.05) but no significant differences in control over the aPFC. These data demonstrate that neurofeedback targeting the aPFC can reduce symptoms in OCD. Future investigations should seek to optimize the training protocol to yield larger effects and to clarify the mechanism of action.

Developing image sets for inducing obsessive-compulsive checking symptoms.

Visual stimuli are often used for obsessive-compulsive (OC) symptom provocation in research studies. We tested the induction of anxiety and OC checking symptoms across different types of checking provocation stimuli in three populations: individuals with obsessive compulsive disorder (OCD), individuals with checking symptoms but without a diagnosis of OCD, and control individuals with neither checking symptoms nor a clinical diagnosis. One set of provocative images depicted objects that are commonly associated with checking anxiety. Another set ('enhanced provocative images') depicted similar objects but also included contextual cues suggesting a specific harmful scenario that could occur. As expected, the enhanced provocative images were more effective at inducing anxiety and OC symptoms than the standard provocative images. Future studies requiring checking symptom provocation should therefore consider incorporating similarly suggestive images. Individuals with clinical OCD reported the greatest provocation in response to these images, followed by those with nonclinical checking, followed by control individuals. Thus, these stimuli are able to provoke OC checking symptoms and anxiety differentially across groups, with the intensity of provocation reflecting diagnostic status. All groups demonstrated a similar qualitative pattern of provocation across images. Finally, in all groups, reported anxiety closely tracked intrusive thoughts and checking urges.

N-acetylcysteine augmentation in serotonin reuptake inhibitor refractory obsessive-compulsive disorder.

RATIONALE: Dysfunction of glutamatergic neurotransmission has been implicated in the pathophysiology of obsessive-compulsive disorder (OCD) and recent clinical reports suggest that some glutamate modulating agents are efficacious in the treatment of this disorder. N-acetylcysteine (NAC) is a readily available amino acid compound that is thought to attenuate glutamatergic neurotransmission. NAC may be useful in treating psychiatric disorders involving glutamatergic dysfunction such as OCD. OBJECTIVES: To examine the efficacy of augmentation with NAC in a patient with serotonin reuptake inhibitor (SRI)-refractory OCD. METHODS: A patient with SRI-refractory OCD was treated with an off-label use of NAC augmentation of fluvoxamine over several weeks. RESULTS: NAC augmentation of fluvoxamine resulted in a marked decrease in Yale-Brown Obsessive Compulsive Scale (Y-BBOCS) score and a clinically significant improvement in OCD symptoms. CONCLUSIONS: NAC augmentation was effective in treating SRI-refractory OCD in this single case. Further research is warranted to investigate the use of NAC and other glutamate modulating agents in the treatment of OCD.

Riluzole augmentation in treatment-resistant obsessive-compulsive disorder: an open-label trial.

BACKGROUND: Most patients with obsessive-compulsive disorder (OCD) show only partial reduction of symptoms with standard therapy. Recent imaging data suggests glutamatergic dysfunction in the corticostriatal pathway in OCD. We investigated the efficacy of augmentation therapy with riluzole, a glutamate-modulating agent, in treatment-resistant OCD. METHODS: Thirteen patients aged between 18 and 65 years with a primary diagnosis of OCD that had proven resistant to standard treatment were treated with the addition of riluzole to their existing pharmacotherapy. Yale-Brown Obsessive Compulsive Scale (Y-BOCS), Hamilton Depression Inventory (HAM-D), and Hamilton Anxiety Inventory (HAM-A) scores were obtained weekly. RESULTS: Thirteen treatment-resistant OCD patients received riluzole 50 mg twice a day. Y-BOCS scores improved significantly over time. Of 13 patients, 7 (54%) demonstrated a >35% reduction in Y-BOCS scores, and 5 (39%) were categorized as treatment responders. HAM-D and HAM-A scores for the group also significantly improved over time. Riluzole was well tolerated with no serious adverse effects noted. CONCLUSIONS: Riluzole appears to have significant antiobsessional, antidepressant, and antianxiety properties. The addition of this agent may be of practical clinical benefit in patients with OCD.

Riluzole augmentation in treatment-refractory obsessive-compulsive disorder: a pilot randomized placebo-controlled trial.

OBJECTIVE: Obsessive-compulsive disorder (OCD) affects approximately 2.5% of the population and is associated with significant morbidity. Many patients receive little benefit from the best available treatments, and even those who do respond often suffer from significant residual symptoms. Convergent evidence suggests that abnormalities in glutamate homeostasis and neurotransmission may contribute to OCD and that glutamate-modulating medications may be of benefit in patients whose symptoms are refractory to standard interventions. Small open-label trials of augmentation of serotonin reuptake inhibitor (SRI) pharmacotherapy with the glutamate modulator riluzole have suggested benefit in adults with refractory symptoms. We report a pilot randomized placebo-controlled trial of riluzole augmentation of ongoing SRI treatment in SRI-refractory patients. METHOD: Outpatients (n = 27) and inpatients (n = 11) with DSM-IV OCD on stable SRI pharmacotherapy were randomized between November 2006 and December 2012 to receive riluzole 50 mg or placebo twice a day and followed for 12 weeks after a 2-week placebo lead-in phase. RESULTS: Riluzole was well tolerated; 1 patient experienced moderate nausea, but none discontinued treatment due to side effects. While there was nominally greater Y-BOCS improvement in the riluzole group (our primary outcome) compared to placebo, it did not reach statistical significance. In the outpatient subsample, a trend suggesting benefit from riluzole augmentation for obsessions (P = .056, 2-tailed, uncorrected) was found in a secondary analysis. Among outpatients, more achieved at least a partial response (> 25% improvement) with riluzole than with placebo (P = .02 in a secondary analysis). CONCLUSIONS: Riluzole may be of benefit to a subset of patients. Larger samples would be required to detect effects of the order suggested by the nominal improvement in our outpatient subsample. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT00523718.

Resting state functional connectivity predicts neurofeedback response.

Tailoring treatments to the specific needs and biology of individual patients-personalized medicine-requires delineation of reliable predictors of response. Unfortunately, these have been slow to emerge, especially in neuropsychiatric disorders. We have recently described a real-time functional magnetic resonance imaging (rt-fMRI) neurofeedback protocol that can reduce contamination-related anxiety, a prominent symptom of many cases of obsessive-compulsive disorder (OCD). Individual response to this intervention is variable. Here we used patterns of brain functional connectivity, as measured by baseline resting-state fMRI (rs-fMRI), to predict improvements in contamination anxiety after neurofeedback training. Activity of a region of the orbitofrontal cortex (OFC) and anterior prefrontal cortex, Brodmann area (BA) 10, associated with contamination anxiety in each subject was measured in real time and presented as a neurofeedback signal, permitting subjects to learn to modulate this target brain region. We have previously reported both enhanced OFC/BA 10 control and improved anxiety in a group of subclinically anxious subjects after neurofeedback. Five individuals with contamination-related OCD who underwent the same protocol also showed improved clinical symptomatology. In both groups, these behavioral improvements were strongly correlated with baseline whole-brain connectivity in the OFC/BA 10, computed from rs-fMRI collected several days prior to neurofeedback training. These pilot data suggest that rs-fMRI can be used to identify individuals likely to benefit from rt-fMRI neurofeedback training to control contamination anxiety.

Global resting-state functional magnetic resonance imaging analysis identifies frontal cortex, striatal, and cerebellar dysconnectivity in obsessive-compulsive disorder.

BACKGROUND: Obsessive-compulsive disorder (OCD) is associated with regional hyperactivity in cortico-striatal circuits. However, the large-scale patterns of abnormal neural connectivity remain uncharacterized. Resting-state functional connectivity studies have shown altered connectivity within the implicated circuitry, but they have used seed-driven approaches wherein a circuit of interest is defined a priori. This limits their ability to identify network abnormalities beyond the prevailing framework. This limitation is particularly problematic within the prefrontal cortex (PFC), which is large and heterogeneous and where a priori specification of seeds is therefore difficult. A hypothesis-neutral, data-driven approach to the analysis of connectivity is vital. METHODS: We analyzed resting-state functional connectivity data collected at 3T in 27 OCD patients and 66 matched control subjects with a recently developed data-driven global brain connectivity (GBC) method, both within the PFC and across the whole brain. RESULTS: We found clusters of decreased connectivity in the left lateral PFC in both whole-brain and PFC-restricted analyses. Increased GBC was found in the right putamen and left cerebellar cortex. Within regions of interest in the basal ganglia and thalamus, we identified increased GBC in dorsal striatum and anterior thalamus, which was reduced in patients on medication. The ventral striatum/nucleus accumbens exhibited decreased global connectivity but increased connectivity specifically with the ventral anterior cingulate cortex in subjects with OCD. CONCLUSIONS: These findings identify previously uncharacterized PFC and basal ganglia dysconnectivity in OCD and reveal differentially altered GBC in dorsal and ventral striatum. Results highlight complex disturbances in PFC networks, which could contribute to disrupted cortical-striatal-cerebellar circuits in OCD.

Histidine decarboxylase deficiency causes tourette syndrome: parallel findings in humans and mice.

Tourette syndrome (TS) is characterized by tics, sensorimotor gating deficiencies, and abnormalities of cortico-basal ganglia circuits. A mutation in histidine decarboxylase (Hdc), the key enzyme for the biosynthesis of histamine (HA), has been implicated as a rare genetic cause. Hdc knockout mice exhibited potentiated tic-like stereotypies, recapitulating core phenomenology of TS; these were mitigated by the dopamine (DA) D2 antagonist haloperidol, a proven pharmacotherapy, and by HA infusion into the brain. Prepulse inhibition was impaired in both mice and humans carrying Hdc mutations. HA infusion reduced striatal DA levels; in Hdc knockout mice, striatal DA was increased and the DA-regulated immediate early gene Fos was upregulated. DA D2/D3 receptor binding was altered both in mice and in humans carrying the Hdc mutation. These data confirm histidine decarboxylase deficiency as a rare cause of TS and identify HA-DA interactions in the basal ganglia as an important locus of pathology.

Effects of ketamine in treatment-refractory obsessive-compulsive disorder.

BACKGROUND: Treatments for obsessive-compulsive disorder (OCD) usually lead to incomplete symptom relief and take a long-time to reach full effect. Convergent evidence suggests that glutamate abnormalities contribute to the pathogenesis of OCD. Ketamine is a potent noncompetitive antagonist of the N-methyl-D-aspartate glutamate receptor. Trials have reported rapid antidepressant effects after low-dose ketamine infusion. METHODS: We conducted an open-label trial of ketamine (.5 mg/kg IV over 40 min) in 10 subjects with treatment-refractory OCD. Response was defined as >35% improvement in OCD symptoms and >50% improvement in depression symptoms from baseline at any time between 1 and 3 days after infusion. RESULTS: None of 10 subjects experienced a response in OCD symptoms in the first 3 days after ketamine. Four of seven patients with comorbid depression experienced an antidepressant response to ketamine in the first 3 days after infusion. Both OCD and depression symptoms demonstrated a statistically significant improvement in the first 3 days after infusion compared with baseline, but the OCD response was <12%. The percentage reduction in depressive symptoms in the first 3 days after ketamine infusion was significantly greater than the reduction in OCD symptoms. CONCLUSIONS: Ketamine effects on OCD symptoms, in contrast to depressive symptoms, did not seem to persist or progress after the acute effects of ketamine had dissipated.