Impulsive behavior and recurrent major depression associated with dandy-walker variant

Tic-Related Obsessive-Compulsive and Eating Disorders in Dandy-Walker Variant: A Case Report and Systematic Reappraisal of Psychiatric Profiles

Dandy-Walker complex (DWC) consists of a continuum of brain malformations involving the posterior fossa, often leading to psychiatric manifestations during adulthood. We discussed the case of a young woman with Dandy-Walker variant (DWV) and a comorbid complex neuropsychiatric presentation, who was diagnosed with an eating disorder, obsessive-compulsive disorder, and a tic disorder. Afterwards, we conducted a Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020-compliant systematic review reappraising all evidence of psychiatric outcomes in adults with DWC. Overall, 34 studies were eligible for data extraction, comprising 36 patients. Psychiatric profiles were more common among young adult males, with DWC lesions, especially DWV subtype, being often discovered incidentally after admission to mental health inpatient facilities. Most patients were diagnosed with psychosis and bipolar disorder, often comorbid with cognitive impairment. Psychotropic polypharmacy was frequently prescribed, generally leading to complete recovery. Evidence from our case report and systematic review indicates the importance of monitoring long-term psychiatric sequelae among adult patients with DWC malformations.

Classification of MDD using a Transformer classifier with large-scale multisite resting-state fMRI data

Major depressive disorder (MDD) is one of the most common psychiatric disorders worldwide with high recurrence rate. Identifying MDD patients, particularly those with recurrent episodes with resting-state fMRI, may reveal the relationship between MDD and brain function. We proposed a Transformer-Encoder model, which utilized functional connectivity extracted from large-scale multisite rs-fMRI datasets to classify MDD and HC. The model discarded the Transformer's Decoder part, reducing the model's complexity and decreasing the number of parameters to adapt to the limited sample size and it does not require a complex feature selection process and achieves end-to-end classification. Additionally, our model is suitable for classifying data combined from multiple brain atlases and has an optional unsupervised pre-training module to acquire optimal initial parameters and speed up the training process. The model's performance was tested on a large-scale multisite dataset and identified brain regions affected by MDD using the Grad-CAM method. After conducting five-fold cross-validation, our model achieved an average classification accuracy of 68.61% on a dataset consisting of 1611 samples. For the selected recurrent MDD dataset, the model reached an average classification accuracy of 78.11%. Abnormalities were detected in the frontal gyri and cerebral cortex of MDD patients in both datasets. Furthermore, the identified brain regions in the recurrent MDD dataset generally exhibited a higher contribution to the model's performance.

Benzodiazepines for Treatment-Resistant Major Depressive Disorder and Obsessive-Compulsive Disorder With Comorbid Mega Cisterna Magna

This article discusses the case of an adult woman with comorbid major depressive disorder (MDD) and obsessive-compulsive disorder (OCD). Due to her poor response to initial treatment regimens, a brain computed tomography (CT) was performed, revealing mega cisterna magna (MCM). Subsequently, she responded well to the addition of lorazepam, a benzodiazepine, along with fluvoxamine and quetiapine XR. The clinical significance of MCM and MDD-OCD remains partially understood. Thus, this case report aims to contribute to the literature and review the treatment of benzodiazepines in relation to MCM, MDD, and OCD comorbidities.

Dandy–Walker malformation and intermittent explosive disorder: A case report

Dandy–Walker malformation is a group of brain malformations that sometimes present with psychotic features, violent and impulsive behavior, or mood symptoms. Here, we present a case report of a patient with Dandy–Walker malformation who presented with intermittent explosive disorder. A young man, aged 18 years, was brought to the author’s hospital [Hamad Medical Corporation] with anger outbursts, irritable mood, and violent behavior. His magnetic resonance imaging scans showed typical alterations of Dandy–Walker malformation. He also had mild intellectual disabilities and epilepsy. After a few weeks of treatment with sodium valproate 1000 mg/day and risperidone 2 mg/day, his condition improved, and his violent behavior was significantly reduced in 3 months, 6 months, and 1 year of follow-up. There is broad consensus that Dandy–Walker malformation is associated with psychosis and other behavioral abnormalities because of a possible disruption in the prefrontal, thalamic, and cerebellar circuits. The link between Dandy–Walker malformation and intermittent explosive disorder may help us understand this type of brain malformation as a potential psychiatric comorbidity.

The Cerebellum on Cocaine

The traditional cerebellum’s role has been linked to the high computational demands for sensorimotor control. However, several findings have pointed to its involvement in executive and emotional functions in the last decades. First in 2009 and then, in 2016, we raised why we should consider the cerebellum when thinking about drug addiction. A decade later, mounting evidence strongly suggests the cerebellar involvement in this disorder. Nevertheless, direct evidence is still partial and related mainly to drug-induced reward memory, but recent results about cerebellar functions may provide new insights into its role in addiction. The present review does not intend to be a compelling revision on available findings, as we did in the two previous reviews. This minireview focuses on specific findings of the cerebellum’s role in drug-related reward memories and the way ahead for future research. The results discussed here provide grounds for involving the cerebellar cortex’s apical region in regulating behavior driven by drug-cue associations. They also suggest that the cerebellar cortex dysfunction may facilitate drug-induced learning by increasing glutamatergic output from the deep cerebellar nucleus (DCN) to the ventral tegmental area (VTA) and neural activity in its projecting areas.

Static and dynamic aspects of cerebro-cerebellar functional connectivity are associated with self-reported measures of impulsivity: A resting-state fMRI study

Human and animal brain studies bring converging evidence of a possible role for the cerebellum and the cerebro-cerebellar system in impulsivity. However, the precise nature of the relation between cerebro-cerebellar coupling and impulsivity is far from understood. Characterizing functional connectivity (FC) patterns between large-scale brain networks that mediate different forms of impulsivity, and the cerebellum may improve our understanding of this relation. Here, we analyzed static and dynamic features of cerebro-cerebellar FC using a highly sampled resting-state functional magnetic resonance imaging (rs-fMRI) dataset and tested their association with two widely used self-reports of impulsivity: the UPPS-P impulsive behavior scale and the behavioral inhibition/approach systems (BIS/BAS) in a large group of healthy subjects (N = 134, ≈ 1 hr of rs-fMRI/subject). We employed robust data-driven techniques to identify cerebral and cerebellar resting-state networks and extract descriptive summary measures of static and dynamic cerebro-cerebellar FC. We observed evidence linking BIS, BAS, sensation seeking, and lack of premeditation to the total strength and temporal variability of FC within networks connecting regions of the prefrontal cortex, precuneus, posterior cingulate cortex, basal ganglia, and thalamus with the cerebellum. Overall, our findings improve the existing knowledge of the neural correlates of impulsivity and the behavioral correlates of the cerebro-cerebellar system.

A Working Hypothesis for the Role of the Cerebellum in Impulsivity and Compulsivity

Growing evidence associates cerebellar abnormalities with several neuropsychiatric disorders in which compulsive symptomatology and impulsivity are part of the disease pattern. Symptomatology of autism, addiction, obsessive-compulsive (OCD), and attention deficit/hyperactivity (ADHD) disorders transcends the sphere of motor dysfunction and essentially entails integrative processes under control of prefrontal-thalamic-cerebellar loops. Patients with brain lesions affecting the cortico-striatum thalamic circuitry and the cerebellum indeed exhibit compulsive symptoms. Specifically, lesions of the posterior cerebellar vermis cause affective dysregulation and deficits in executive function. These deficits may be due to impairment of one of the main functions of the cerebellum, implementation of forward internal models of the environment. Actions that are independent of internal models may not be guided by predictive relationships or a mental representation of the goal. In this review article, we explain how this deficit might affect executive functions. Additionally, regionalized cerebellar lesions have been demonstrated to impair other brain functions such as the emergence of habits and behavioral inhibition, which are also altered in compulsive disorders. Similar to the infralimbic cortex, clinical studies and research in animal models suggest that the cerebellum is not required for learning goal-directed behaviors, but it is critical for habit formation. Despite this accumulating data, the role of the cerebellum in compulsive symptomatology and impulsivity is still a matter of discussion. Overall, findings point to a modulatory function of the cerebellum in terminating or initiating actions through regulation of the prefrontal cortices. Specifically, the cerebellum may be crucial for restraining ongoing actions when environmental conditions change by adjusting prefrontal activity in response to the new external and internal stimuli, thereby promoting flexible behavioral control. We elaborate on this explanatory framework and propose a working hypothesis for the involvement of the cerebellum in compulsive and impulsive endophenotypes.

Dandy-Walker Malformation-Like Condition Revealed by Refractory Schizophrenia: A Case Report and Literature Review

INTRODUCTION

Dandy-Walker malformation is a rare congenital malformation involving cystic dilatation of the fourth ventricle, enlarged posterior fossa, complete or partial agenesis of the cerebellar vermis, elevated tentorium cerebelli, and hydrocephalus. Previous research highlighted a possible role for the cerebellum in schizophrenia as well as the contribution of underlying brain malformations to treatment resistance. Here, we present a case of a Dandy-Walker malformation-like condition revealed by a refractory schizophrenia in a 24-year-old male patient. We also conduct a literature review of all previously published case reports or case series of co-occurring posterior fossa abnormalities and schizophrenia or psychosis using a PubMed search query to better understand the potential link between these two disorders.

CASE PRESENTATION

A 9-month hospital stay was needed to address the treatment-resistant psychotic symptoms, and the patient continued to experience moderate symptoms despite the prescription of various antipsychotic and antidepressant medications. After an irregular initial medical follow-up, the patient is currently treated with 350 mg daily clozapine and 20 mg daily prazepam and still exhibits moderate anxiety without delirious thoughts, however allowing him to re-enroll at the university. Regarding the literature, 24 cases published between 1996 and 2017 were identified, reviewed and compared to the present case report.

DISCUSSION

This case report and literature review further illuminates the pathophysiology of psychotic disorders including the potential role of the cerebellum, reinforces the importance of a multidisciplinary approach for the neurological and psychiatric management of patients with schizophrenia, and highlights optimal pharmacological management strategies for treatment-resistant schizophrenia.

The Most Common Comorbidities in Dandy-Walker Syndrome Patients: A Systematic Review of Case Reports

OBJECTIVE

Dandy-Walker syndrome (DWS) is a rare neurologic multi-entity malformation. This review aimed at reporting its main nonneurologic comorbidities.

METHODS

Following PRISMA guidelines, search in Medline was conducted (2000-2014, keyword: dandy-walker). Age, sex, country, DWS type, consanguinity or siblings with DWS, and recorded coexistent conditions (by ICD10 category) were extracted for 187 patients (46.5% male, 43% from Asia) from 168 case reports.

RESULTS

Diagnosis was most often set in <1 year old (40.6%) or >12 years old (27.8%). One-third of cases had a chromosomal abnormality or syndrome (n = 8 PHACE), 27% had a cardiovascular condition (n = 7 Patent Ductus Arteriosus), 24% had a disease of eye and ear (n = 9 cataract); most common malignancy was nephroblastoma (n = 8, all Asian). Almost one-fifth had a mental illness diagnosis; only 6.4% had mild or severe intellectual disability.

CONCLUSION

The spread of comorbidities calls for early diagnosis and multidisciplinary research and practice, especially as many cases remain clinically asymptomatic for years.

Dandy-Walker Malformation Presenting with Psychological Manifestations

Dandy-Walker malformation, which is a congenital malformation of the cerebellum, is documented in literature to be associated with psychotic symptoms, obsessive compulsive symptoms, mood symptoms, hyperactivity, and impulsive behavior. The pathogenesis of psychiatric symptoms in Dandy-Walker malformation is thought to be due to disruption of the corticocerebellar tracts, resulting in what is known as cerebellar cognitive affective syndrome. We present a case of Dandy-Walker malformation presenting with psychiatric symptoms. This case highlights the necessity to be aware of psychiatric manifestations of cerebellar disease as it has an impact on the diagnosis and treatment.