Background: Major depressive disorder (MDD) is a leading cause of disability worldwide, with available treatments often showing limited efficacy. Recent research suggests targeting specific subtypes of depression and understanding the underlying brain mechanisms can improve treatment outcomes. This study investigates the potential of the potassium KCNQ (Kv7) channel opener ezogabine to modulate the resting-state functional connectivity (RSFC) of the brain's reward circuitry and alleviate depressive symptoms, including anhedonia, a core feature of MDD.
View Article and Find Full Text PDFBackground: Motivated behaviors vary widely across individuals and are controlled by a range of environmental and intrinsic factors. However, due to a lack of objective measures, the role of intrinsic extrinsic control of motivation in psychiatric disorders remains poorly understood.
Methods: We developed a novel multi-factorial behavioral task that separates the distinct contributions of intrinsic extrinsic control, and determines their influence on motivation and outcome sensitivity in a range of contextual environments.
Background: Major depressive disorder (MDD) is a prevalent health problem with complex pathophysiology that is not clearly understood. Prior work has implicated the hippocampus in MDD, but how hippocampal subfields influence or are affected by MDD requires further characterization with high-resolution data. This will help ascertain the accuracy and reproducibility of previous subfield findings in depression as well as correlate subfield volumes with MDD symptom scores.
View Article and Find Full Text PDFObjectives: Traumatic stress has been associated with increased risk for brain alterations and development of anxiety disorders. Studies conducted in posttraumatic patients have shown white-mater volume and diffusion alterations in the corpus-callosum. Decreased cognitive performance has been demonstrated in acute stress disorder and posttraumatic patients.
View Article and Find Full Text PDFThe ventral tegmental area (VTA) is one of the major sources of dopamine in the brain and has been associated with reward prediction, error-based reward learning, volitional drive and anhedonia. However, precise anatomical investigations of the VTA have been prevented by the use of standard-resolution MRI, reliance on subjective manual tracings, and lack of quantitative measures of dopamine-related signal. Here, we combine ultra-high field 400 µm quantitative MRI with dopamine-related signal mapping, and a mixture of machine learning and supervised computational techniques to delineate the VTA in a transdiagnostic sample of subjects with and without depression and anxiety disorders.
View Article and Find Full Text PDFStud Health Technol Inform
June 2022
Digital Pills are a drug-device technology that allow for the combination of traditional medications with a monitoring system that automatically records data about medication adherence and patients' physiological data. They are a promising innovation in digital medicine; however, their use has raised a number of ethical concerns. In this paper, we outline some of the main Digital Pills technologies and explore key ethical challenges surrounding their use.
View Article and Find Full Text PDFThe hippocampus and amygdala limbic structures are critical to the etiology of major depressive disorder (MDD). However, there are no high-resolution characterizations of the role of their subregions in the whole brain network (connectome). Connectomic examination of these subregions can uncover disorder-related patterns that are otherwise missed when treated as single structures.
View Article and Find Full Text PDFPurpose: Epilepsy patients exhibit morphological differences on neuroimaging compared to age-matched healthy controls, including cortical and sub-cortical volume loss and altered gray-white matter ratios. The objective was to develop a model of normal aging using the 7T MRIs of healthy controls. This model can then be used to determine if the changes in epilepsy patients resemble the changes seen in aging, and potentially give a marker for the severity of those changes.
View Article and Find Full Text PDFBackground: Arousal and awareness are two important components of consciousness states. Functional neuroimaging has furthered our understanding of cortical and thalamocortical mechanisms of awareness. Investigating the relationship between subcortical functional connectivity and arousal has been challenging owing to the relatively small size of brainstem structures and thalamic nuclei, and their depth in the brain.
View Article and Find Full Text PDFBackground: Trigeminal Neuralgia (TN) is a chronic neurological disease that is strongly associated with neurovascular compression (NVC) of the trigeminal nerve near its root entry zone. The trigeminal nerve at the site of NVC has been extensively studied but limbic structures that are potentially involved in TN have not been adequately characterized. Specifically, the hippocampus is a stress-sensitive region which may be structurally impacted by chronic TN pain.
View Article and Find Full Text PDFBackground: A growing body of literature addresses the possible long-term cognitive effects of anaesthetics, but no study has delineated the normal trajectory of neural recovery attributable to anaesthesia alone in adults. We obtained resting-state functional MRI scans on 72 healthy human volunteers between ages 40 and 80 (median: 59) yr before, during, and after general anaesthesia with sevoflurane, in the absence of surgery, as part of a larger study on cognitive function postanaesthesia.
Methods: Region-of-interest analysis, independent component analysis, and seed-to-voxel analysis were used to characterise resting-state functional connectivity and to differentiate between correlated and anticorrelated connectivity before, during, and after general anaesthesia.
Neurorehabil Neural Repair
September 2020
. Nigrostriatal dopaminergic loss is a hallmark of Parkinson's disease (PD) pathophysiology, leading to motor Parkinsonism. Different intervention protocols have shown that motor and cognitive functions improvement in PD occur the modulation of distinct motor and cognitive pathways.
View Article and Find Full Text PDFIntroduction: Falls are associated with numerous risk factors, such as motor and cognitive impairments. However, the neural correlates of falls are poorly understood.
Objectives: Here, we aimed to assess patterns of structural, and resting-state functional connectivity (FC) alterations related to falls in a group of older adults with a history of falls compared to non-fallers.
Patients with major depressive disorder (MDD) exhibit higher levels of rumination, i.e., repetitive thinking patterns and exaggerated focus on negative states.
View Article and Find Full Text PDFIntroduction: Deficits in executive function and attention have been associated with freezing of gait (FOG) in patients with Parkinson's disease (PD). However, the exact changes in the ventral and dorsal attentional networks that may contribute to FOG are unknown. Our aim was to examine the changes in connectivity of the attentional networks in patients with PD and their role in FOG.
View Article and Find Full Text PDFNon-manifesting carriers (NMC) of the G2019S mutation in the LRRK2 gene represent an "at risk" group for future development of Parkinson's disease (PD) and have demonstrated task related fMRI changes. However, resting-state networks have received less research focus, thus this study aimed to assess the integrity of the motor, default mode (DMN), salience (SAL), and dorsal attention (DAN) networks among this unique population by using two different connectivity measures: interregional functional connectivity analysis and Dependency network analysis (D NA). Machine learning classification methods were used to distinguish connectivity between the two groups of participants.
View Article and Find Full Text PDFEmotion regulation is hypothesized to be mediated by the interactions between emotional reactivity and regulation networks during the dynamic unfolding of the emotional episode. Yet, it remains unclear how to delineate the effective relationships between these networks. In this study, we examined the aforementioned networks' information flow hierarchy during viewing of an anger provoking movie excerpt.
View Article and Find Full Text PDFTransl Psychiatry
January 2018
Impairments in social cognition and interactions are core psychopathologies in schizophrenia, often manifesting as an inability to appropriately relate to the intentions and feelings of others. Neuroimaging has helped to demarcate the dynamics of two distinct functional connectivity circuits underlying the social-affective processes related to mentalization (known as Theory of Mind, ToM) and somatic-affiliation (known as Embodied Simulation, ES). While evidence points to abnormal activation patterns within these networks among those suffering from schizophrenia, it is yet unclear however, if these patients exhibit this abnormal functional connectivity in the context of social-affective experiences.
View Article and Find Full Text PDFObjective: To compare the effects of 2 forms of exercise, i.e., a 6-week trial of treadmill training with virtual reality (TT + VR) that targets motor and cognitive aspects of safe ambulation and a 6-week trial of treadmill training alone (TT), on brain activation in patients with Parkinson disease (PD).
View Article and Find Full Text PDFAlloparental care, the cooperative care of offspring by group members other than the biological mother, has been widely practiced since early hominin evolution to increase infant survival and thriving. The coparental bond-a relationship of solidarity and commitment between two adults who join their effort to care for children-is a central contributor to children's well-being and sociality; yet, the neural basis of coparenting has not been studied in humans. Here, we followed 84 first-time co-parents (42 couples) across the first 6 years of family formation, including opposite-sex and same-sex couples, measured brain response to coparental stimuli, observed collaborative and undermining coparental behaviors in infancy and preschool, assayed oxytocin (OT) and vasopressin (AVP), and measured coparenting and child behavior problems at 6 years.
View Article and Find Full Text PDFWe introduce a novel method for delineating context-dependent functional brain networks whose connectivity dynamics are synchronized with the occurrence of a specific psychophysiological process of interest. In this method of context-related network dynamics analysis (CRNDA), a continuous psychophysiological index serves as a reference for clustering the whole-brain into functional networks. We applied CRNDA to fMRI data recorded during the viewing of a sadness-inducing film clip.
View Article and Find Full Text PDFObjectives: Patients with Parkinson's disease (PD) can be classified, based on their motor symptoms into the Postural Instability Gait Difficulty (PIGD) subtype or the Tremor Dominant (TD) subtype. Gray matter changes between the subtypes have been reported using whole brain Voxel-Based Morphometry (VBM), however, the evaluation of subcortical gray matter volumetric differences between these subtypes using automated volumetric analysis has only been studied in relatively small sample sizes and needs further study to confirm that the negative findings were not due to the sample size. Therefore, we aimed to evaluate volumetric changes in subcortical regions and their association with PD motor subtypes.
View Article and Find Full Text PDFPatients with Parkinson's disease (PD) have difficulties in executive functions including conflict monitoring. The neural mechanisms underlying these difficulties are not yet fully understood. In order to examine the neural mechanisms related to conflict monitoring in PD, we evaluated 35 patients with PD and 20 healthy older adults while they performed a word-color Stroop paradigm in the MRI.
View Article and Find Full Text PDFCommunication between and within brain regions is essential for information processing within functional networks. The current methods to determine the influence of one region on another are either based on temporal resolution, or require a predefined model for the connectivity direction. However these requirements are not always achieved, especially in fMRI studies, which have poor temporal resolution.
View Article and Find Full Text PDFRecent theoretical and empirical work has highlighted the role of domain-general, large-scale brain networks in generating emotional experiences. These networks are hypothesized to process aspects of emotional experiences that are not unique to a specific emotional category (e.g.
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