Multimodal MRI cerebral correlates of verbal fluency switching and its impairment in women with depression.

BACKGROUND: The search of biomarkers in the field of depression requires easy implementable tests that are biologically rooted. Qualitative analysis of verbal fluency tests (VFT) are good candidates, but its cerebral correlates are unknown. METHODS: We collected qualitative semantic and phonemic VFT scores along with grey and white matter anatomical MRI of depressed (n = 26) and healthy controls (HC, n = 25) women. Qualitative VFT variables are the "clustering score" (i.e. the ability to produce words within subcategories) and the "switching score" (i.e. the ability to switch between clusters). The clustering and switching scores were automatically calculated using a data-driven approach. Brain measures were cortical thickness (CT) and fractional anisotropy (FA). We tested for associations between CT, FA and qualitative VFT variables within each group. RESULTS: Patients had reduced switching VFT scores compared to HC. Thicker cortex was associated with better switching score in semantic VFT bilaterally in the frontal (superior, rostral middle and inferior gyri), parietal (inferior parietal lobule including the supramarginal gyri), temporal (transverse and fusiform gyri) and occipital (lingual gyri) lobes in the depressed group. Positive association between FA and the switching score in semantic VFT was retrieved in depressed patients within the corpus callosum, right inferior fronto-occipital fasciculus, right superior longitudinal fasciculus extending to the anterior thalamic radiation (all p < 0.05, corrected). CONCLUSION: Together, these results suggest that automatic qualitative VFT scores are associated with brain anatomy and reinforce its potential use as a surrogate for depression cerebral bases.

Functional connectivity and cognitive changes after donepezil treatment in healthy participants.

RATIONALE: Donepezil is a potent, noncompetitive, reversible, clinically effective acetylcholinesterase inhibitor. The effects of this drug on healthy brains have seldom been investigated. OBJECTIVES: The primary objective of the present study was to identify possible functional connectivity markers of the effect of donepezil in healthy young adult volunteers. METHODS: The study had a double-blind, randomized, crossover design. 30 healthy adult volunteers underwent resting-state MRI scans during 15 days of donepezil or placebo treatment, in accordance with the design. RESULTS: Results showed significant differences in intrinsic functional connectivity between donepezil and placebo, mainly in the right executive control network (RECN). More specifically, we found a decrease in the connectivity of the right inferior parietal node with other RECN nodes. Analysis using the cingulate cortex and parahippocampal regions as seeds also revealed complex modulation of functional connectivity in the donepezil condition. CONCLUSIONS: In conclusion, donepezil treatment for 15 days may result in reorganization of resting-state networks, compared with placebo.

[Supervised off-label prescribing of methylphenidate in adult ADHD]. / Prescriptions hors AMM supervisées de méthylphénidate dans le TDAH de l'adulte.

OBJECTIVE: Off-label prescription is a common practice in psychiatry, raising health and economic concerns. Collegial consultation could allow a framed prescription of treatments that are not authorized in specific indications. Attention Deficit Hyperactivity in adult populations (ADHD) is a striking example of a pathology where off-label prescription is frequent. First considered to be a childhood disorder, the awareness of this condition in adults is increasing, leading to the development of new clinical practices and treatments. However, the adult ADHD diagnosis and its management are still emerging in France despite a high prevalence. Treatment of adult ADHD relies on methylphenidate prescription, but the initiation of this drug is not authorized in adult populations. Methylphenidate is a central nervous system stimulant that is structurally close to amphetamine and acts as a norepinephrine and dopamine reuptake inhibitor. Due to these pharmacological properties, neuropsychiatric and cardiovascular side-effects could occur. Furthermore, its addictive potential has led France to classify it as a psychoactive drug, dispensed via secured prescription. The first prescription and the one-year follow-up are restricted to neurologists, paediatrics, psychiatrists and sleep disorders specialists at hospital. The objective of this article is to propose a multidisciplinary framework for the off-label prescription of methylphenidate in adult ADHD. METHODS: The Multidisciplinary Advice Consultation for Exceptional Addiction Treatments (Consultation d'Avis Multidisciplinaire de Traitements d'Exception en Addictologie CAMTEA) was first set up in Lille for the prescription of baclofen in alcohol dependence and was then extended to topiramate in binge eating disorder. This procedure has been adapted to the particularities of ADHD in adult populations, the differential diagnosis (bipolar disorder, depressive disorder, anxious disorder, personality disorder, substance use disorder) and the co-morbidities requiring a full psychiatric and neuropsychological assessment. Moreover, a particular attention has been paid to the monitoring of neuropsychiatric, cardiovascular and misuse risk because of the potential side-effects of methylphenidate. RESULTS: The proposed prescription framework is structured into several specialized consultations. A first psychiatric evaluation aims to diagnose adult ADHD, using the French version of the Diagnostisch Interview Voor ADHD 2.0 questionnaire (DIVA 2.0), and to assess the quality of life impact with the Weiss Functional Inventory Rating Scale (WIFRS). It also searches for the presence of differential diagnosis or co-morbidities. The second appointment consists of a pharmacological evaluation that aims to search for contraindications and potential drug interaction. A neuropsychological evaluation based on standardized tests (Weschler Adulte Intelligence Scale [WAIS IV], Conner's Continuous Performance Test 3 [CPT] and the Minnesota Multiphasic Personnality Inventory [MMPI]) is also required to evaluate neurocognitive disabilities and personality features. Once the parameters of the different assessments have been collected, the synthesis is presented during a multidisciplinary meeting in order to assess the risk-benefit ratio for each patient. Several specialties are involved in this multidisciplinary meeting: psychiatry, addictology, general medicine, addictovigilance, pharmacovigilance and neuropsychology. One strategy among three possibilities can be decided: (1) contraindication to treatment with methylphenidate, (2) attention deficit disorder that does not require medication management, and (3) indication of treatment with methylphenidate with the choice of the pharmacological form (immediate or prolonged release). A biological check-up and an electrocardiogram are carried out systematically before any treatment. If the decision is made to initiate treatment, it is started at the lowest dosage and followed by a titration phase. A weekly follow-up is carried out during the titration phase in order to assess treatment efficacy and safety. After treatment stabilization, the general practitioner can carry out the renewal, and the patient will be reassessed within the framework of the multidisciplinary consultation every 3 months. CONCLUSION: When an off-label prescription is being considered, it must comply with the basic rules of good clinical practice, and the benefit/risk ratio should be constantly reassessed. The proposed multidisciplinary framework, adapted to the characteristics of adult ADHD and the pharmacological properties of methylphenidate, appears to be an interesting strategy to meet the requirements of the good clinical practice. The complementary assessments carried out and the collegial framework allow enhancing the patient's follow-up and minimize the drug risk, particularly in the psychiatric, addictive and cardiovascular adverse events. Finally, this framework could also help the monitoring of other off-label treatments for ADHD, such as atomoxetine or guanfacine.

Repetitive transcranial magnetic stimulation over the orbitofrontal cortex for obsessive-compulsive disorder: a double-blind, crossover study.

This pilot study was designed to assess the efficacy of low-frequency repetitive transcranial magnetic stimulation (rTMS) over the right orbitofrontal cortex (OFC) by means of a double-cone coil in patients suffering from obsessive-compulsive disorder. We hypothesized that low-frequency stimulation of the OFC would lead to a reduction in clinical symptoms, as measured on the Yale-Brown Obsessive Compulsive Scale (Y-BOCS). A randomized, double-blind, crossover design was implemented with two 1-week treatment periods (active stimulation versus sham stimulation) separated by a 1-month washout period. Concomitantly, a subgroup of patients underwent a positron emission tomography (PET) scan after each stimulation sequence. Statistical analyses compared the Y-BOCS scores at the end of each period. At day 7, we observed a significant decrease from baseline in the Y-BOCS scores, after both active (P<0.01) and sham stimulation (P=0.02). This decrease tended to be larger after active stimulation than after sham stimulation: -6 (-29, 0) points versus -2 (-20, 4) points (P=0.07). Active versus sham PET scan contrasts showed that stimulation was related to a bilateral decrease in the metabolism of the OFC. The OFC should definitely be regarded as a key neuroanatomical target for rTMS, as it is easier to reach than either the striatum or the subthalamic nucleus, structures favored in neurosurgical approaches.

[Emotion and basal ganglia (II): what can we learn from subthalamic nucleus deep brain stimulation in Parkinson's disease?]. / Émotion et noyaux gris centraux (II) : que peut-nous apprendre le modèle de la stimulation cérébrale profonde du noyau subthalamique dans la maladie de Parkinson ?

The subthalamic nucleus deep-brain stimulation Parkinson's disease patient model seems to represent a unique opportunity for studying the functional role of the basal ganglia and notably the subthalamic nucleus in human emotional processing. Indeed, in addition to constituting a therapeutic advance for severely disabled Parkinson's disease patients, deep brain stimulation is a technique, which selectively modulates the activity of focal structures targeted by surgery. There is growing evidence of a link between emotional impairments and deep-brain stimulation of the subthalamic nucleus. In this context, according to the definition of emotional processing exposed in the companion paper available in this issue, the aim of the present review will consist in providing a synopsis of the studies that investigated the emotional disturbances observed in subthalamic nucleus deep brain stimulation Parkinson's disease patients. This review leads to the conclusion that several emotional components would be disrupted after subthalamic nucleus deep brain stimulation in Parkinson's disease: subjective feeling, neurophysiological activation, and motor expression. Finally, after a description of the limitations of this study model, we discuss the functional role of the subthalamic nucleus (and the striato-thalamo-cortical circuits in which it is involved) in emotional processing. It seems reasonable to conclude that the striato-thalamo-cortical circuits are indeed involved in emotional processing and that the subthalamic nucleus plays a central in role the human emotional architecture.

[Emotion and basal ganglia (I): what can we learn from Parkinson's disease?]. / Émotion et noyaux gris centraux (I) : que peut nous apprendre la maladie de Parkinson ?

Parkinson's disease provides a useful model for studying the neural substrates of emotional processing. The striato-thalamo-cortical circuits, like the mesolimbic dopamine system that modulates their function, are thought to be involved in emotional processing. As Parkinson's disease is histopathologically characterized by the selective, progressive and chronic degeneration of the nigrostriatal and mesocorticolimbic dopamine systems, it can therefore serve as a model for assessing the functional role of these circuits in humans. In the present review, after a definition of emotional processing from a multicomponential perspective, a synopsis of the emotional disturbances observed in Parkinson's disease is proposed. Note that the studies on the affective consequences of subthalamic nucleus deep brain stimulation in Parkinson's disease were excluded from this review because the subject of a companion paper in this issue. This review leads to the conclusion that several emotional components would be disrupted in Parkinson's disease: subjective feeling, neurophysiological activation, and motor expression. We then discuss the functional roles of the striato-thalamo-cortical and mesolimbic circuits, ending with the conclusion that both these pathways are indeed involved in emotional processing.