Nucleus accumbens deep brain stimulation for a patient with self-injurious behavior and autism spectrum disorder: functional and structural changes of the brain: report of a case and review of literature

Potential Neuroimaging Biomarkers for Autism Spectrum Disorder: A Comprehensive Review of MR Imaging, fMR Imaging, and PET Studies

Autism spectrum disorder (ASD) is a characteristically heterogeneous disorder, as multiple neurodevelopmental disorders are characterized by similar symptomology and behavior. Research has shown that individuals with ASD benefit from early intervention; neuroimaging data may reveal information that cannot be obtained from traditional behavioral analysis. This review discusses the use of structural MR imaging, functional MR imaging (fMR imaging), and PET in the detection of ASD. Larger datasets, standardized methods of collection and analysis, and more robust meta-analyses are required to implement the observed biomarkers and improve the lives of patients living with AUD.

Exploring the most discriminative brain structural abnormalities in ASD with multi-stage progressive feature refinement approach

Objective

Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by increasing prevalence, diverse impairments, and unclear origins and mechanisms. To gain a better grasp of the origins of ASD, it is essential to identify the most distinctive structural brain abnormalities in individuals with ASD.

Methods

A Multi-Stage Progressive Feature Refinement Approach was employed to identify the most pivotal structural magnetic resonance imaging (MRI) features that distinguish individuals with ASD from typically developing (TD) individuals. The study included 175 individuals with ASD and 69 TD individuals, all aged between 7 and 18 years, matched in terms of age and gender. Both cortical and subcortical features were integrated, with a particular focus on hippocampal subfields.

Results

Out of 317 features, 9 had the most significant impact on distinguishing ASD from TD individuals. These structural features, which include a specific hippocampal subfield, are closely related to the brain areas associated with the reward system.

Conclusion

Structural irregularities in the reward system may play a crucial role in the pathophysiology of ASD, and specific hippocampal subfields may also contribute uniquely, warranting further investigation.

Effectiveness of deep brain stimulation on refractory aggression in pediatric patients with autism and severe intellectual disability: meta-analytic review

Some patients with autism and severe intellectual disability may experience uncontrolled aggression, causing serious injury or harm to others, and the therapeutic ineffectiveness of traditional pharmacological and behavioral treatment may aggravate symptoms. Deep brain stimulation (DBS) has been tested in patients with little evidence in children and adolescents. Therefore, we analyzed the efficacy and safety of DBS in refractory aggression in pediatric subjects with autism (ASD) and severe intelligence deficit (ID).Methods A meta-analytic review of Web of Science (WOS) and Scopus articles, following Prisma criteria. A total of 555 articles were identified, but after applying the inclusion criteria, only 18 were analyzed. The review of the registries and the extraction of information was performed by 2 independent groups, to reduce the evaluator's bias. For the description of the results, pediatric patients with ASD or ID present in each registry, with an application of specialized scales (Overt aggression scale, OAS, and THE modified version of the OAS, MOAS) pre and post-DBS, with a clinical follow-up of at least 12 months, were considered valid. Clinical improvement was calculated using tests of aggressiveness. In each registry with available data and then pooling the means of all patients in the OAS and MOAS, the effect size of DBS (overall and per study) was estimated. Finally, the adapted NOS scale was applied to rate the studies' quality and level of bias.Results In the studies analyzed, 65/100 were pediatric patients, with a mean age of 16.8 years. Most of the studies were conducted in South America and Europe. In all teams, aggressive behavior was intractable, but only 9 groups (53/65) applied specialized scales to measure aggressiveness, and of these, only 51 subjects had a follow-up of at least 12 months. Thus, in 48/51 a clinical improvement of patients was estimated (94.2%), with a considerable overall effect size (OAS: d = 4.32; MOAS: d = 1.46). However, adverse effects and complications were found in 13/65 subjects undergoing DBS. The brain target with the most evidence and the fewest side effects was the posteromedial hypothalamic nuclei (pHypN). Finally, applying the adapted NOS scale, quality, and bias, only 9 studies show the best indicators.Conclusion An optimal level of efficacy was found in only half of the publications. This is mainly due to design errors and irrelevant information in the reports. We believe that DBS in intractable aggressiveness in children and adolescents with ASD and severe ID can be safe and effective if working groups apply rigorous criteria for patient selection, interdisciplinary assessments, objective scales for aggressiveness, and known surgical targets.

Tics emergencies and malignant tourette syndrome: Assessment and management

Tourette syndrome (TS) is a complex neurodevelopmental disorder characterized by the presence of tics, frequently accompanied by a variety of neuropsychiatric comorbidities. A subset of patients with TS present with severe and disabling symptoms, requiring prompt therapeutic intervention. Some of these manifestations may result in medical emergencies when severe motor or phonic tics lead to damage of anatomical structures closely related to the tic. Examples include myelopathy or radiculopathy following severe neck ("whiplash") jerks or a variety of self-inflicted injuries. In addition to self-aggression or, less commonly, allo-aggression, some patients exhibit highly inappropriate behavior, suicidal tendencies, and rage attacks which increase the burden of the disease and are important components of "malignant TS". This subset of TS is frequently associated with comorbid obsessive-compulsive disorder. Therapeutic measures include intensive behavioral therapy, optimization of oral pharmacotherapy, botulinum toxin injections, and deep brain stimulation.

Abnormal individualized peak functional connectivity toward potential repetitive transcranial magnetic stimulation treatment of autism spectrum disorder

Functional connectivity (FC) derived from resting-state functional magnetic resonance imaging has been widely applied to guide precise repetitive transcranial magnetic stimulation (rTMS). The left, right, and bilateral dorsolateral prefrontal cortices (DLPFC) have been used as rTMS treatment target regions for autism spectrum disorder (ASD), albeit with moderate efficacy. Thus, we aimed to develop an individualized localization method for rTMS treatment of ASD. We included 266 male ASDs and 297 male typically-developed controls (TDCs) from the Autism Brain Imaging Data Exchange Dataset. The nucleus accumbens (NAc) was regarded as a promising effective region, which was used as a seed and individualized peak FC strength in the DLPFC was compared between ASD and TDC. Correlation analysis was conducted between individualized peak FC strength and symptoms in ASD. We also investigated the spatial distribution of individualized peak FC locations in the DLPFC and conducted voxel-wise analysis to compare NAc-based FC between the two groups. ASD showed stronger peak FC in the right DLPFC related to TDC (Cohen's d = -.19, 95% CI: -0.36 to -0.03, t = -2.30, p = .02). Moreover, negative correlation was found between the peak FC strength in the right DLPFC and Autism Diagnostic Observation Schedule (ADOS) scores, which assessed both the social communication and interaction (r = -.147, p = .04, uncorrected significant), and stereotyped behaviors and restricted interests (r = -.198, p = .02, corrected significant). Peak FC locations varied substantially across participants. No significant differences in NAc-based FC in the DLPFC were found in the voxel-wise comparison. Our study supports the use of individualized peak FC-guided precise rTMS treatment of male ASD. Moreover, stimulating the right DLPFC might alleviate core symptoms of ASD.

Headache in Individuals with Neurodevelopmental Disorders

PURPOSE OF REVIEW

Migraine is a common condition affecting an estimated billion people across the world. The incidence in individuals with neurodevelopmental disorders or intellectual disabilities like those seen in severe autism spectrum disorder (ASD) is unknown. This is likely due to the limited capacity to communicate the specifics of pain. The expression of pain with maladaptive behaviors, such as self-injurious behavior (SIB), has been described and can alert the clinician to the presence of untreated pain. This review article serves to educate the reader about clinical and treatment considerations when managing headaches in individuals with severe or non-verbal neurodevelopmental disorders given their communication challenges. It will include some clinical experiences and the gaps in our current knowledge.

RECENT FINDINGS

A comprehensive literature review was conducted using scientific databases, including PubMed, Medline, and Google Scholar. Only 1 article addressed the consideration for headaches in this population. The search was conducted using a combination of the following keywords: headache, intellectual disabilities, autism, pain, and behavior. Headache pain is likely underestimated and represents a disservice to this population of people. The consideration for headache pain should be explored when maladaptive behaviors are otherwise unexplainable. Further studies are needed in the area.

The dopamine hypothesis of autism spectrum disorder: A comprehensive analysis of the evidence

Despite intensive research into the etiopathogenesis of autism spectrum disorder (ASD), limited progress has been achieved so far. Among the plethora of models seeking to clarify how ASD arises, a coherent dopaminergic model was lacking until recently. In 2017, we provided a theoretical framework that we designated "the dopamine hypothesis of ASD". In the meantime, numerous studies yielded empirical evidence for this model. 4 years later, we provided a second version encompassing a refined and reconceptualized framework that accounted for these novel findings. In this chapter, we will review the evidence backing the previous versions of our model and add the most recent developments to the picture. Along these lines, we intend to lay out a comprehensive analysis of the supporting evidence for the dopamine hypothesis of ASD.

Deep brain stimulation may be a viable option for resistant to treatment aggression in children with intellectual disability

INTRODUCTION

Deep brain stimulation (DBS) is a surgical technique used to manage aggression in patients who do not improve despite the use of appropriate drug treatment.

OBJECTIVE

The objective of this study is to assess the impact of DBS on aggressive behavior refractory to the pharmacological and behavioral treatment of patients with Intellectual Disabilities (ID).

METHODS

A follow-up was conducted on a cohort of 12 patients with severe ID, undergoing DBS in posteromedial hypothalamic nuclei; evaluated with the Overt Aggression Scale (OAS), before the intervention, at 6, 12, and 18 months of medical follow-up.

RESULTS

After the surgical procedure, there was a significant reduction in the aggressiveness of patients in the follow-up medical evaluation at 6 months (t = 10.14; p < 0.01), 12 months (t = 14.06; p < 0.01), and 18 months (t = 15.34; p < 0.01), respect to the initial measurement; with a very large effect size (6 months: d = 2.71; 12 months: d = 3.75; 18 months: d = 4.10). From 12 months onward, emotional control stabilized and is sustained at 18 months (t = 1.24; p > 0.05).

CONCLUSION

DBS in posteromedial hypothalamic nuclei may be an effective treatment for the management of aggression in patients with ID refractory to pharmacological treatment.

Deep brain stimulation for autism spectrum disorder

Deep brain stimulation (DBS) is a medical treatment that aims to obtain therapeutic effects by applying chronic electrical impulses in specific brain structures and neurological circuits. Over the years, DBS has been studied for the treatment of many psychiatric disorders. Scientific research on the use of DBS in people with autism has focused this interest mainly on treatment-resistant obsessive-compulsive disorder, drug-resistant epilepsy, self-injurious behaviors (SIB), and aggressive behaviors toward the self. Autism spectrum disorder (ASD) includes a group of developmental disabilities characterized by patterns of delay and deviance in the development of social, communicative, and cognitive skills and the presence of repetitive and stereotyped behaviors as well as restricted interests. People with autism often have numerous medical and psychiatric comorbidities that worsen the quality of life of patients and their caregivers. Obsessive-compulsive symptoms can be found in up to 81.3% of people with autism. They are often severe, refractory to treatment, and particularly difficult to treat. SIB has a high prevalence in severely retarded individuals and is often associated with autism. Drug treatment of both autism and SIB presents a therapeutic challenge. To describe the current state of the art regarding the efficacy of DBS in people with ASD, a literature search was conducted for relevant studies using the PubMed database. Thirteen studies have been considered in this paper. Up to date, DBS has been used for the stimulation of the nucleus accumbens, globus pallidus internus, anterior limb of the internal capsule, ventral anterior limb of the internal capsule, basolateral amygdala, ventral capsule and ventral striatum, medial forebrain bundle, and posterior hypothalamus. In the total sample of 16 patients, 4 were adolescents, and 12 were adults. All patients had symptoms resistant to multiple drug therapy. Many patients taken into consideration by the studies showed clinical improvements as evidenced by the scores of the psychopathological scales used. In some cases, clinical improvements have varied over time, which may require further investigation. Among the new therapeutic perspectives, DBS could be a valid option. However, further, and more in-depth research is needed in this field.

Stereotactic neurosurgery as a symptomatic treatment for autism spectrum disorders: A systematic review

Stereotactic neurosurgery has been employed in autism spectrum disorders (ASD). However, its safety and effectiveness remain unclear owing to limited sample size and other methodological limitations. We aimed to systematically investigate the safety and efficacy of stereotactic neurosurgery for ASD. Eleven studies with 36 patients were included. Stereotactic neurosurgery alleviated the obsessive-compulsive disorder and aggressive behavior symptoms in ASD, with a mean improvement of 42.74% and 59.59% in the Yale-Brown Obsessive Compulsive Scale and Overt Aggression Scale scores, respectively. Systematic studies are necessary to explore the role of deep brain stimulation for social and communication difficulties in ASD.

Striatal increase of dopamine receptor 2 density in idiopathic and syndromic mouse models of autism spectrum disorder

Autism spectrum disorder (ASD) comprises a wide range of neurodevelopmental phenotypes united by impaired social interaction and repetitive behavior. Environmental and genetic factors are associated with the pathogenesis of ASD, while other cases are classified as idiopathic. The dopaminergic system has a profound impact in the modulation of motor and reward-motivated behaviors, and defects in dopaminergic circuits are implicated in ASD. In our study, we compare three well-established mouse models of ASD, one idiopathic, the BTBR strain, and two syndromic, Fmr1 and Shank3 mutants. In these models, and in humans with ASD, alterations in dopaminergic metabolism and neurotransmission were highlighted. Still, accurate knowledge about the distribution of dopamine receptor densities in the basal ganglia is lacking. Using receptor autoradiography, we describe the neuroanatomical distribution of D1 and D2 receptors in dorsal and ventral striatum at late infancy and adulthood in the above-mentioned models. We show that D1 receptor binding density is different among the models irrespective of the region. A significant convergence in increased D2 receptor binding density in the ventral striatum at adulthood becomes apparent in BTBR and Shank3 lines, and a similar trend was observed in the Fmr1 line. Altogether, our results confirm the involvement of the dopaminergic system, showing defined alterations in dopamine receptor binding density in three well-established ASD lines, which may provide a plausible explanation to some of the prevalent traits of ASD. Moreover, our study provides a neuroanatomical framework to explain the utilization of D2-acting drugs such as Risperidone and Aripiprazole in ASD.

Deep brain stimulation for extreme behaviors associated with autism spectrum disorder converges on a common pathway: a systematic review and connectomic analysis

OBJECTIVE

Individuals with autism spectrum disorder (ASD) may display extreme behaviors such as self-injury or aggression that often become refractory to psychopharmacology or behavioral intervention. Deep brain stimulation (DBS) is a surgical alternative that modulates brain circuits that have yet to be clearly elucidated. In the current study the authors performed a connectomic analysis to identify brain circuitry engaged by DBS for extreme behaviors associated with ASD.

METHODS

A systematic review was performed to identify prior reports of DBS as a treatment for extreme behaviors in patients with ASD. Individual patients' perioperative imaging was collected from corresponding authors. DBS electrode localization and volume of tissue activated modeling were performed. Volumes of tissue activated were used as seed points in high-resolution normative functional and structural imaging templates. The resulting individual functional and structural connectivity maps were pooled to identify networks and pathways that are commonly engaged by all targets.

RESULTS

Nine patients with ASD who were receiving DBS for symptoms of aggression or self-injurious behavior were identified. All patients had some clinical improvement with DBS. Connectomic analysis of 8 patients (from the systematic review and unpublished clinical data) demonstrated a common anatomical area of shared circuitry within the anterior limb of the internal capsule. Functional analysis of 4 patients identified a common network of distant brain areas including the amygdala, insula, and anterior cingulate engaged by DBS.

CONCLUSIONS

This study presents a comprehensive synopsis of the evidence for DBS in the treatment of extreme behaviors associated with ASD. Using network mapping, the authors identified key circuitry common to DBS targets.

Positron Emission Tomography in the Neuroimaging of Autism Spectrum Disorder: A Review

Autism spectrum disorder (ASD) is a basket term for neurodevelopmental disorders characterized by marked impairments in social interactions, repetitive and stereotypical behaviors, and restricted interests and activities. Subtypes include (A) disorders with known genetic abnormalities including fragile X syndrome, Rett syndrome, and tuberous sclerosis and (B) idiopathic ASD, conditions with unknown etiologies. Positron emission tomography (PET) is a molecular imaging technology that can be utilized in vivo for dynamic and quantitative research, and is a valuable tool for exploring pathophysiological mechanisms, evaluating therapeutic efficacy, and accelerating drug development in ASD. Recently, several imaging studies on ASD have been published and physiological changes during ASD progression was disclosed by PET. This paper reviews the specific radioligands for PET imaging of critical biomarkers in ASD, and summarizes and discusses the similar and different discoveries in outcomes of previous studies. It is of great importance to identify general physiological changes in cerebral glucose metabolism, cerebral blood flow perfusion, abnormalities in neurotransmitter systems, and inflammation in the central nervous system in ASD, which may provide excellent points for further ASD research.

An open-label prospective pilot trial of nucleus accumbens deep brain stimulation for children with autism spectrum disorder and severe, refractory self-injurious behavior: study protocol

BACKGROUND

Children and youth with autism spectrum disorder (ASD) may manifest self-injurious behaviors (SIB) that may become severe and refractory with limited pharmacologic or behavioral treatment options. Here, we present the protocol of a prospective, mixed-methods study to assess the safety and efficacy of deep brain stimulation (DBS) of the nucleus accumbens (NAcc) for children and youth with ASD and severe, refractory SIB.

METHODS

This is a prospective, single-center, single-cohort, open-label, non-randomized pilot trial of 6 patients. Participants will be recruited through specialized behavioral clinics with persistent severe and refractory SIB following standard and intensive interventions. Following NAcc-DBS, participants will be enrolled in the study for 12 months. The primary objectives of the study are safety and feasibility, assessed by rate of recruitment and identification of factors impacting adherence to follow-up and study protocol. Potential treatment efficacy will be assessed by changes in the Children's Yale-Brown Obsessive-Compulsive Scale in ASD (CYBOCS-ASD), the Behavior Problems Index (BPI), the Inventory of Statements about Self-Injury (ISAS) and the Repetitive Behavior Scale-Revised (RBS-R) questionnaires. Additional clinical outcomes will be assessed, including measures of participant and caregiver quality of life, actigraph measurements, and positron emission tomography (PET) changes following DBS.

DISCUSSION

This study will be the first to evaluate the effect of DBS of the NAcc on a pediatric population in a controlled, prospective trial. Secondary outcomes will improve the understanding of behavioral, neuro-imaging, and electrophysiologic changes in children with ASD and SIB treated with DBS. This trial will provide an estimated effect size of NAcc-DBS for severe refractory SIB in children with ASD in preparation for future comparative trials.

TRIAL REGISTRATION

Registration on ClinicalTrials.gov was completed on 12 June 2019 with the Identifier: NCT03982888 .

Habenula as a Neural Substrate for Aggressive Behavior

Over the past decades, an ever growing body of literature has explored the anatomy, connections, and functions of the habenula (Hb). It has been postulated that the Hb plays a central role in the control of the monoaminergic system, thus influencing a wide range of behavioral responses, and participating in the pathophysiology of a number of psychiatric disorders and neuropsychiatric symptoms, such as aggressive behaviors. Aggressive behaviors are frequently accompanied by restlessness and agitation, and are commonly observed in patients with psychiatric disorders, intellectual disabilities, and neurodegenerative diseases of aging. Recently, the Hb has been explored as a new target for neuromodulation therapies, such as deep brain stimulation, with promising results. Here we review the anatomical organization of the habenula and discuss several distinct mechanisms by which the Hb is involved in the modulation of aggressive behaviors, and propose new investigations for the development of novel treatments targeting the habenula to reduce aggressive behaviors.

Brain stimulation: a therapeutic approach for the treatment of neurological disorders

Brain stimulation has become one of the most acceptable therapeutic approaches in recent years and a powerful tool in the remedy against neurological diseases. Brain stimulation is achieved through the application of electric currents using non-invasive as well as invasive techniques. Recent technological advancements have evolved into the development of precise devices with capacity to produce well-controlled and effective brain stimulation. Currently, most used non-invasive techniques are repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS), whereas the most common invasive technique is deep brain stimulation (DBS). In last decade, application of these brain stimulation techniques has not only exploded but also expanded to wide variety of neurological disorders. Therefore, in the current review, we will provide an overview of the potential of both non-invasive (rTMS and tDCS) and invasive (DBS) brain stimulation techniques in the treatment of such brain diseases.

Disrupted functional connectivity between the nucleus accumbens and posterior cingulate cortex in autism spectrum disorder

OBJECTIVES

Dysfunctions in the basal ganglia have been repeatedly found in autism spectrum disorder (ASD). The nucleus accumbens (NAcc) is known for its central role in social functions and also in its abnormality in ASD. In this study, whole-brain functional connectivity of the NAcc was examined to isolate brain regions that are differently connected to the NAcc in autism, using resting-state functional MRI (rs-fMRI) data.

METHODS

In the initial dataset, 68 individuals with ASD (13.13 ± 2.41 years old) and 77 typically developing individuals (14.79 ± 3.57 years old) were compared.

RESULTS

The precuneus cortex, lingual gyrus, thalamus, dorsal striatum, anterior cingulate cortex and posterior cingulate cortex showed weaker connectivity to the NAcc in the group with ASD. Among these regions, dysconnectivity of the posterior cingulate cortex (PCC) was replicated in the replication dataset, with 78 individuals with ASD and 105 without ASD.

CONCLUSIONS

This study suggests that the dysconnectivity between the NAcc and PCC may account for social dysfunctions in ASD.

Treating Aggression and Self-destructive Behaviors by Stimulating the Nucleus Accumbens: A Case Series

Self-destructive and aggressive behaviors can have a significant impact on the quality of life of affected individuals and their carrers. While deep brain stimulation (DBS) has been applied to the treatment of self-destructive and aggressive behaviors in isolated cases, clinical data on this treatment modality are still lacking. We therefore assessed responses to treatment with bilateral DBS of the nucleus accumbens in six patients with severe self-destructive and aggressive behaviors. Three patients had Tourette syndrome and three had other underlying predispositions including obsessive compulsive disorder, cerebral palsy, encephalitis, and epilepsy. Patients were followed up for between 2 and 7 years, and patients were assessed using the Modified Overt Aggression Scale (six patients) and the Buss-Perry Aggression Questionnaire (three patients able to complete the questionnaire on their own). DBS reduced self-destructive and aggressive behaviors by 30–100% and by an average of 74.5%. Patients with Tourette syndrome responded better to DBS and improved by 27.3% according to the Buss-Perry Aggression Questionnaire. These results suggest that nuclei accumbens stimulation may be an effective treatment for aggressive and self-destructive behaviors regardless of etiology.

Self-injurious behavior in Tourette syndrome

INTRODUCTION

Tourette syndrome (TS) is characterized by the presence of motor and phonic tics, as well as a variety of behavioral co-morbidities. Self-injurious behavior (SIB) is one of the most serious manifestations of TS, but its pathophysiology is poorly understood.

METHODS

Consecutive patients with TS studied in a tertiary care center.

RESULTS

We identified a total of 34 patients (16.9%) with SIB from a cohort of 201 patients with TS. Most of these patients (n = 23, 11.4%) experienced self-directed damage; while others had outward-directed (n = 7, 3.5%) or tic-related SIB (n = 4, 2%). Compared to other patients with TS, those who manifested SIB (self- and outward-directed damage) were more likely to have tics involving shoulder (P = 0.046), trunk (P = 0.006), and arm (P = 0.017); as well as dystonic tics (P = 0.016); complex motor tics (P < 0.001), copropraxia (P = 0.045), complex phonic tics (P = 0.003), higher number of phonic tics (P = 0.001), verbalizations (P = 0.001), coprolalia (P = 0.006) and obsessive compulsive disorder (OCD) (P < 0.001) as determined by bivariate analysis. In the multivariate analysis only complex motor tics (P = 0.006), obsessive-compulsive behavior (P = 0.025) and greater severity of tics (P = 0.002) showed a statistically significant association with SIB. Patients with SIB had a greater probability of being selected for deep brain stimulation (DBS) therapy by the treating clinician (P = 0.01).

CONCLUSIONS

SIB is observed in about 17% of patients with TS. The presence of complex motor tics, OCD and greater severity of tics was related to the presence of SIB.

Mood Regulatory Actions of Active and Sham Nucleus Accumbens Deep Brain Stimulation in Antidepressant Resistant Rats

The antidepressant actions of deep brain stimulation (DBS) are associated with progressive neuroadaptations within the mood network, modulated in part, by neurotrophic mechanisms. We investigated the antidepressant-like effects of chronic nucleus accumbens (NAc) DBS and its association with change in glycogen synthase kinase 3 (GSK3) and mammalian target of rapamycin (mTOR) expression in the infralimbic cortex (IL), and the dorsal (dHIP) and ventral (vHIP) subregions of the hippocampus of antidepressant resistant rats. Antidepressant resistance was induced via daily injection of adrenocorticotropic hormone (ACTH; 100 μg/day; 15 days) and confirmed by non-response to tricyclic antidepressant treatment (imipramine, 10 mg/kg). Portable microdevices provided continuous bilateral NAc DBS (130 Hz, 200 μA, 90 μs) for 7 days. A control sham electrode group was included, together with ACTH- and saline-treated control groups. Home cage monitoring, open field, sucrose preference, and, forced swim behavioral tests were performed. Post-mortem levels of GSK3 and mTOR, total and phosphorylated, were determined with Western blot. As previously reported, ACTH treatment blocked the immobility-reducing effects of imipramine in the forced swim test. In contrast, treatment with either active DBS or sham electrode placement in the NAc significantly reduced forced swim immobility time in ACTH-treated animals. This was associated with increased homecage activity in the DBS and sham groups relative to ACTH and saline groups, however, no differences in locomotor activity were observed in the open field test, nor were any group differences seen for sucrose consumption across groups. The antidepressant-like actions of NAc DBS and sham electrode placements were associated with an increase in levels of IL and vHIP phospho-GSK3β and phospho-mTOR, however, no differences in these protein levels were observed in the dHIP region. These data suggest that early response to electrode placement in the NAc, irrespective of whether active DBS or sham, has antidepressant-like effects in the ACTH-model of antidepressant resistance associated with distal upregulation of phospho-GSK3β and phospho-mTOR in the IL and vHIP regions of the mood network.

The Dopamine Hypothesis of Autism Spectrum Disorder Revisited: Current Status and Future Prospects

Autism spectrum disorder (ASD) comprises a group of neurodevelopmental disorders characterized by social deficits and stereotyped behaviors. Despite intensive research, its etiopathogenesis remains largely unclear. Although studies consistently reported dopaminergic anomalies, a coherent dopaminergic model of ASD was lacking until recently. In 2017, we provided a theoretical framework for a "dopamine hypothesis of ASD" which proposed that autistic behavior arises from a dysfunctional midbrain dopaminergic system. Namely, we hypothesized that malfunction of 2 critical circuits originating in the midbrain, that is, the mesocorticolimbic and nigrostriatal pathways, generates the core behavioral features of ASD. Moreover, we provided key predictions of our model along with testing means. Since then, a notable number of studies referenced our work and numerous others provided support for our model. To account for these developments, we review all these recent data and discuss their implications. Furthermore, in the light of these new insights, we further refine and reconceptualize our model, debating on the possibility that various etiologies of ASD converge upon a dysfunctional midbrain dopaminergic system. In addition, we discuss future prospects, providing new means of testing our hypothesis, as well as its limitations. Along these lines, we aimed to provide a model which, if confirmed, could provide a better understanding of the etiopathogenesis of ASD along with new therapeutic strategies.

Disconnecting surgery at alveus and cornu ammonis of hippocampus, amygdala superficialis, and amygdala medial nuclei for epilepsy associated with attention deficit hyperactivity disorder

The neural basis for epilepsy and attention deficit hyperactivity disorder (ADHD) is currently incompletely known. We reported a young girl with both epilepsy and ADHD, who had a calcified lesion in the right basolateral amygdalo-hippocampal region extending to the ventral striatum. The child underwent disconnecting surgery and biopsy of the lesion. Fascinatingly, the child's behavior changed immediately after the surgery from inattentive and impulsive to nearly normal behavior experiencing no more breakthrough seizures since after 3 years of surgery. The Schaltenbrand Wahren Brain Atlas revealed alveus, cornu ammonis, amygdala superficialis, and medium as the disconnected region in this surgery.

Structural, Functional, and Molecular Imaging of Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a heterogeneous neurodevelopmental disorder associated with both genetic and environmental risks. Neuroimaging approaches have been widely employed to parse the neurophysiological mechanisms underlying ASD, and provide critical insights into the anatomical, functional, and neurochemical changes. We reviewed recent advances in neuroimaging studies that focused on ASD by using magnetic resonance imaging (MRI), positron emission tomography (PET), or single-positron emission tomography (SPECT). Longitudinal structural MRI has delineated an abnormal developmental trajectory of ASD that is associated with cascading neurobiological processes, and functional MRI has pointed to disrupted functional neural networks. Meanwhile, PET and SPECT imaging have revealed that metabolic and neurotransmitter abnormalities may contribute to shaping the aberrant neural circuits of ASD. Future large-scale, multi-center, multimodal investigations are essential to elucidate the neurophysiological underpinnings of ASD, and facilitate the development of novel diagnostic biomarkers and better-targeted therapy.

Deep Brain Stimulation for Obsessive-Compulsive Disorder: Real World Experience Post-FDA-Humanitarian Use Device Approval

Background: While case series have established the efficacy of deep brain stimulation (DBS) in treating obsessive-compulsive disorder (OCD), it has been our experience that few OCD patients present without comorbidities that affect outcomes associated with DBS treatment. Here we present our experience with DBS therapy for OCD in patients who all have comorbid disease, together with the results of our programming strategies. Methods: For this case series, we assessed five patients who underwent ventral capsule/ventral striatum (VC/VS) DBS for OCD between 2015 and 2019 at the University of Colorado Hospital. Every patient in this cohort exhibited comorbidities, including substance use disorders, eating disorder, tic disorder, and autism spectrum disorder. We conducted an IRB-approved, retrospective study of programming modifications and treatment response over the course of DBS therapy. Results: In addition to patients' subjective reports of improvement, we observed significant improvement in the Yale-Brown Obsessive-Compulsive Scale (44%), the Montgomery-Asberg Depression Rating Scale (53%), the Quality of Life Enjoyment and Satisfaction Questionnaire (27%), and the Hamilton Anxiety Rating scales (34.9%) following DBS. With respect to co-morbid disease, there was a significant improvement in a patient with tic disorder's Total Tic Severity Score (TTSS) (p = 0.005). Conclusions: DBS remains an efficacious tool for the treatment of OCD, even in patients with significant comorbidities in whom DBS has not previously been investigated. Efficacious treatment results not only from the accurate placement of the electrodes by the surgeon but also from programming by the psychiatrist.

Cerebellar oscillations driven by synaptic pruning deficits of cerebellar climbing fibers contribute to tremor pathophysiology

Essential tremor (ET) is one of the most common movement disorders and the prototypical disorder for abnormal rhythmic movements. However, the pathophysiology of tremor generation in ET remains unclear. Here, we used autoptic cerebral tissue from patients with ET, clinical data, and mouse models to report that synaptic pruning deficits of climbing fiber (CF)-to-Purkinje cell (PC) synapses, which are related to glutamate receptor delta 2 (GluRδ2) protein insufficiency, cause excessive cerebellar oscillations and might be responsible for tremor. The CF-PC synaptic pruning deficits were correlated with the reduction in GluRδ2 expression in the postmortem ET cerebellum. Mice with GluRδ2 insufficiency and CF-PC synaptic pruning deficits develop ET-like tremor that can be suppressed with viral rescue of GluRδ2 protein. Step-by-step optogenetic or pharmacological inhibition of neuronal firing, axonal activity, or synaptic vesicle release confirmed that the activity of the excessive CF-to-PC synapses is required for tremor generation. In vivo electrophysiology in mice showed that excessive cerebellar oscillatory activity is CF dependent and necessary for tremor and optogenetic-driven PC synchronization was sufficient to generate tremor in wild-type animals. Human validation by cerebellar electroencephalography confirmed that excessive cerebellar oscillations also exist in patients with ET. Our findings identify a pathophysiologic contribution to tremor at molecular (GluRδ2), structural (CF-to-PC synapses), physiological (cerebellar oscillations), and behavioral levels (kinetic tremor) that might have clinical applications for treating ET.

Modulation of Theta-Band Local Field Potential Oscillations Across Brain Networks With Central Thalamic Deep Brain Stimulation to Enhance Spatial Working Memory

Deep brain stimulation (DBS) is a well-established technique for the treatment of movement and psychiatric disorders through the modulation of neural oscillatory activity and synaptic plasticity. The central thalamus (CT) has been indicated as a potential target for stimulation to enhance memory. However, the mechanisms underlying local field potential (LFP) oscillations and memory enhancement by CT-DBS remain unknown. In this study, we used CT-DBS to investigate the mechanisms underlying the changes in oscillatory communication between the CT and hippocampus, both of which are involved in spatial working memory. Local field potentials (LFPs) were recorded from microelectrode array implanted in the CT, dentate gyrus, cornu ammonis (CA) region 1, and CA region 3. Functional connectivity (FC) strength was assessed by LFP-LFP coherence calculations for these brain regions. In addition, a T-maze behavioral task using a rat model was performed to assess the performance of spatial working memory. In DBS group, our results revealed that theta oscillations significantly increased in the CT and hippocampus compared with that in sham controls. As indicated by coherence, the FC between the CT and hippocampus significantly increased in the theta band after CT-DBS. Moreover, Western blotting showed that the protein expressions of the dopamine D1 and α4-nicotinic acetylcholine receptors were enhanced, whereas that of the dopamine D2 receptor decreased in the DBS group. In conclusion, the use of CT-DBS resulted in elevated theta oscillations, increased FC between the CT and hippocampus, and altered synaptic plasticity in the hippocampus, suggesting that CT-DBS is an effective approach for improving spatial working memory.

MR imaging central thalamic deep brain stimulation restored autistic-like social deficits in the rat

BACKGROUND

Social deficit is a core symptom in autism spectrum disorder (ASD). Although deep brain stimulation (DBS) has been proposed as a potential treatment for ASD, an ideal target nucleus is yet to be identified. DBS at the central thalamic nucleus (CTN) is known to alter corticostriatal and limbic circuits, and subsequently increase the exploratory motor behaviors, cognitive performance, and skill learning in neuropsychiatric and neurodegenerative disorders.

OBJECTIVE

We first investigated the ability of CTN-DBS to selectively engage distinct brain circuits and compared the spatial distribution of evoked network activity and modulation. Second, we investigated whether CTN-DBS intervention improves social interaction in a valproic acid-exposed ASD rat offspring model.

METHODS

Brain regions activated through CTN-DBS by using a magnetic resonance (MR)-compatible neural probe, which is capable of inducing site-selective microstimulations during functional MRI (fMRI), were investigated. We then performed functional connectivity MRI, the three-chamber social interaction test, and Western blotting analyses to evaluate the therapeutic efficacy of CTN-DBS in an ASD rat offspring model.

RESULTS

The DBS-evoked fMRI results indicated that the activated brain regions were mainly located in cortical areas, limbic-related areas, and the dorsal striatum. We observed restoration of brain functional connectivity (FC) in corticostriatal and corticolimbic circuits after CTN-DBS, accompanied with increased social interaction and decreased social avoidance in the three-chamber social interaction test. The dopamine D2 receptor decreased significantly after CTN-DBS treatment, suggesting changes in synaptic plasticity and alterations in the brain circuits.

CONCLUSIONS

Applying CTN-DBS to ASD rat offspring increased FC and altered the synaptic plasticity in the corticolimbic and the corticostriatal circuits. This suggests that CTN-DBS could be an effective treatment for improving the social behaviors of individuals with ASD.

Amygdala and Hypothalamus: Historical Overview With Focus on Aggression

Aggressiveness has a high prevalence in psychiatric patients and is a major health problem. Two brain areas involved in the neural network of aggressive behavior are the amygdala and the hypothalamus. While pharmacological treatments are effective in most patients, some do not properly respond to conventional therapies and are considered medically refractory. In this population, surgical procedures (ie, stereotactic lesions and deep brain stimulation) have been performed in an attempt to improve symptomatology and quality of life. Clinical results obtained after surgery are difficult to interpret, and the mechanisms responsible for postoperative reductions in aggressive behavior are unknown. We review the rationale and neurobiological characteristics that may help to explain why functional neurosurgery has been proposed to control aggressive behavior.

Translating striatal activity from brain slice to whole animal neurophysiology: A guide for neuroscience research integrating diverse levels of analysis

An important goal of this review is highlighting research in neuroscience as examples of multilevel functional and anatomical analyses addressing basic science issues and applying results to the understanding of diverse disorders. The research of Dr. Michael Levine, a leader in neuroscience, exemplifies this approach by uncovering fundamental properties of basal ganglia function and translating these findings to clinical applications. The review focuses on neurophysiological research connecting results from in vitro and in vivo recordings. A second goal is to utilize these research connections to produce novel, accurate descriptions for corticostriatal processing involved in varied, complex functions. Medium spiny neurons in striatum act as integrators combining input with baseline activity creating motivational "events." Basic research on corticostriatal synapses is described and links developed to issues with clinical relevance such as inhibitory gating, self-injurious behavior, and relative reward valuation. Work is highlighted on dopamine-glutamate interactions. Individual medium spiny neurons express both D₁ and D₂ receptors and encode information in a bivalent manner depending upon the mix of receptors involved. Current work on neurophysiology of reward processing has taken advantage of these basic approaches at the cellular and molecular levels. Future directions in studying physiology of reward processing and action sequencing could profit by incorporating the divergent ways dopamine modulates incoming neurochemical signals. Primary investigators leading research teams should mirror Mike Levine's efforts in "climbing the mountain" of scientific inquiry by performing analyses at different levels of inquiry, integrating the findings, and building comprehensive answers to problems unsolvable without this bold approach.

Nucleus Accumbens Deep Brain Stimulation for Obsessive-Compulsive Disorder and Aggression in an Autistic Patient: A Case Report and Hypothesis of the Role of Nucleus Accumbens in Autism and Comorbid Symptoms

BACKGROUND

Autism spectrum disorder represents a set of developmental disorders characterized by lack of social interaction and verbal and nonverbal communication in the first 3 years of life. It is also associated with several comorbidities, including epilepsy, aggression, self-mutilating behavior, and obsessive-compulsive behavior. In some cases, obsessive-compulsive disorder (OCD) develops. The nucleus accumbens (NAc) plays a key role in reward circuitry and is involved in the control of OCD and aggression.

CASE DESCRIPTION

A 42-year-old woman with autism was offered NAc deep brain stimulation for her comorbidities of OCD and aggression. The NAc was targeted using standard stereotactic methods, and postoperative scans confirmed the position of the active electrode to be within the NAc. The patient experienced significant symptom relief. At 1-year follow-up, the Yale-Brown Obsessive Compulsive Scale score for OCD, excluding items 1-5 of the scale, improved from 19 to 5. Hamilton Depression Scale and Hamilton Anxiety Scale scores similarly improved from 20 to 15 and from 30 to 18, respectively. Social Communication Questionnaire Current version for autism score improved from 26 to 16. Subscores for reciprocal social interactionimproved from 13 to 8; for communication improved from 5 to 4; and for restricted, repetitive, and stereotyped patterns of behavior improved from 6 to 3.

CONCLUSIONS

This case report illustrated the role of the NAc in OCD and aggression in an autistic patient. We discussed the role of the NAc as a target to explain the outcome of this case.

Pharmacological Treatment of Body Dysmorphic Disorder

Body dysmorphic disorder is a challenging disorder that manifests as erroneously perceived flaws in one’s physical appearance and repetitive behaviors in response to appearance concerns. This disorder is also frequently comorbid with other psychiatric disorders, including major depressive disorder and autism spectrum disorder. It is currently understood to arise from a combination of biological, psychological, and environmental factors. Treatment of body dysmorphic disorder typically consists of a combination of pharmacotherapy and cognitive behavioral therapy. However, not all patients respond to treatment, and BDD symptoms remain even in those who do respond. This review outlines current pharmacological and neuromodulation treatments for body dysmorphic disorder and suggests directions for future studies of novel treatments such as augmentation with atypical antipsychotics and the use of intranasal oxytocin in cases of body dysmorphic disorder that show residual symptomatology even with tailored monotherapy. There is emerging evidence suggesting that non-invasive neurostimulatory techniques, such as repetitive transcranial magnetic stimulation, may be of value in treatment-resistant cases.

New perspectives in the treatment of body dysmorphic disorder

Body dysmorphic disorder (BDD) is a disabling illness with a high worldwide prevalence. Patients demonstrate a debilitating preoccupation with one or more perceived defects, often marked by poor insight or delusional convictions. Multiple studies have suggested that selective serotonin reuptake inhibitors and various cognitive behavioral therapy modalities are effective first-line treatments in decreasing BDD severity, relieving depressive symptoms, restoring insight, and increasing quality of life. Selective serotonin reuptake inhibitors have also recently been shown to be effective for relapse prevention. This review provides a comprehensive summary of the current understanding of BDD, including its clinical features, epidemiology, genetics, and current treatment modalities. Additional research is needed to fully elucidate the relationship between BDD and comorbid illnesses such as obsessive–compulsive-related disorders and depression and to develop therapies for refractory patients and those who have contraindications for pharmacological intervention.