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Minerva Medica Dec 2023
Topics: Humans; Putamen; Punctures
PubMed: 37293891
DOI: 10.23736/S0026-4806.23.08662-7 -
Sleep Medicine Dec 2021Although several studies have shown the involvement of specific structures of the central nervous system, the dopaminergic system, and iron metabolism in restless legs...
BACKGROUND
Although several studies have shown the involvement of specific structures of the central nervous system, the dopaminergic system, and iron metabolism in restless legs syndrome (RLS), the exact location and extent of its anatomical substrate is not yet known. The scope of this new study was to investigate the brain subcortical gray structures, by means of structural magnetic resonance imaging (MRI) studies, in RLS patients in order to assess the presence of any volume or shape abnormalities involving these structures.
METHODS
Thirty-three normal controls (24 females and nine males) and 45 RLS patients (34 females and 11 males) were retrospectively recruited and underwent a 1.5 Tesla MRI study with two-dimensional T1 sequences in the sagittal plane. Post-processing was performed by means of the Functional Magnetic Resonance Imaging of the Brain Analysis Group Integrated Registration and Segmentation Tool (FIRST) software, and both volumetric and morphological analyses of the thalamus, caudate, putamen, globus pallidus, brainstem, hippocampus, and amygdala, bilaterally, were carried out.
RESULTS
A statistically significant volumetric reduction in the left amygdala and left globus pallidus was found in subjects with RLS, as well as large surface morphological alterations affecting the amygdala bilaterally and other less widespread surface changes in both hippocampi, the right caudate, the left globus pallidus, and the left putamen.
CONCLUSIONS
These findings seem to indicate that the basic mechanisms of RLS might include a pathway involving not only the hypothalamus-spinal dopaminergic circuit (nucleus A11), but also pathways including the basal ganglia and structures that are part of the limbic system; moreover, structural alterations in RLS seem to concern the morphology as well as the volume of the above structures. The role of basal ganglia in the complex neurophysiological and neurochemical mechanism of RLS needs to carefully reconsidered.
Topics: Brain; Female; Humans; Magnetic Resonance Imaging; Male; Putamen; Restless Legs Syndrome; Retrospective Studies
PubMed: 34740168
DOI: 10.1016/j.sleep.2021.10.025 -
Journal of Neuroscience Research May 2021Mindfulness is a meditation practice frequently associated with changes in subjective evaluation of cognitive and sensorial experience, as well as with modifications of...
Mindfulness is a meditation practice frequently associated with changes in subjective evaluation of cognitive and sensorial experience, as well as with modifications of brain activity and morphometry. Aside from the anatomical localization of functional changes induced by mindfulness practice, little is known about changes in functional and effective functional magnetic resonance imaging (fMRI) connectivity. Here we performed a connectivity fMRI analysis in a group of healthy individuals participating in an 8-week mindfulness-based stress reduction (MBSR) training program. Data from both a "mind-wandering" and a "meditation" state were acquired before and after the MBSR course. Results highlighted decreased local connectivity after training in the right anterior putamen and insula during spontaneous mind-wandering and the right cerebellum during the meditative state. A further effective connectivity analysis revealed (a) decreased modulation by the anterior cingulate cortex over the anterior portion of the putamen, and (b) a change in left and right posterior putamen excitatory input and inhibitory output with the cerebellum, respectively. Results suggest a rearrangement of dorsal striatum functional and effective connectivity in response to mindfulness practice, with changes in cortico-subcortical-cerebellar modulatory dynamics. Findings might be relevant for the understanding of widely documented mindfulness behavioral effects, especially those related to pain perception.
Topics: Adult; Cerebellum; Corpus Striatum; Female; Humans; Male; Meditation; Mindfulness; Nerve Net; Stress, Psychological
PubMed: 33634892
DOI: 10.1002/jnr.24798 -
Cerebral Cortex (New York, N.Y. : 1991) Jun 2022The striatum and cerebral cortex are interconnected via multiple recurrent loops that play a major role in many neuropsychiatric conditions. Primate corticostriatal...
The striatum and cerebral cortex are interconnected via multiple recurrent loops that play a major role in many neuropsychiatric conditions. Primate corticostriatal connections can be precisely mapped using invasive tract-tracing. However, noninvasive human research has not mapped these connections with anatomical precision, limited in part by the practice of averaging neuroimaging data across individuals. Here we utilized highly sampled resting-state functional connectivity MRI for individual-specific precision functional mapping (PFM) of corticostriatal connections. We identified ten individual-specific subnetworks linking cortex-predominately frontal cortex-to striatum, most of which converged with nonhuman primate tract-tracing work. These included separable connections between nucleus accumbens core/shell and orbitofrontal/medial frontal gyrus; between anterior striatum and dorsomedial prefrontal cortex; between dorsal caudate and lateral prefrontal cortex; and between middle/posterior putamen and supplementary motor/primary motor cortex. Two subnetworks that did not converge with nonhuman primates were connected to cortical regions associated with human language function. Thus, precision subnetworks identify detailed, individual-specific, neurobiologically plausible corticostriatal connectivity that includes human-specific language networks.
Topics: Animals; Brain Mapping; Corpus Striatum; Frontal Lobe; Humans; Magnetic Resonance Imaging; Motor Cortex; Neural Pathways; Nucleus Accumbens; Prefrontal Cortex; Putamen
PubMed: 34718460
DOI: 10.1093/cercor/bhab387 -
European Journal of Neurology Apr 2021To explore the feasibility of a neuroprotection trial in prodromal synucleinopathy, using idiopathic rapid eye movement sleep behavior disorder (iRBD) as the target... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND AND PURPOSE
To explore the feasibility of a neuroprotection trial in prodromal synucleinopathy, using idiopathic rapid eye movement sleep behavior disorder (iRBD) as the target population and I-FP-CIT-SPECT as a biomarker of disease progression.
METHODS
Consecutive iRBD patients were randomly assigned to a treatment arm receiving selegiline and symptomatic rapid eye movement sleep behavior disorder treatment, or to a control arm receiving symptomatic treatment only. Selegiline was chosen because of a demonstrated neuroprotection effect in animal models. Patients underwent I-FP-CIT-SPECT at baseline and after 30 months on average. The clinical outcome was the emergence of parkinsonism and/or dementia. A repeated-measures general linear model (GLM) was applied using group (control and treatment) as "between" factor, and both time (baseline and follow-up) and regions ( I-FP-CIT-SPECT putamen and caudate uptake) as the "within" factors, adjusting for age.
RESULTS
Thirty iRBD patients completed the study (68.2 ± 6.9 years; 29 males; 21% dropout rate), 13 in the treatment arm, and 17 in the control arm. At follow-up (29.8 ± 9.0 months), three patients in the control arm developed dementia and one parkinsonism, whereas two patients in the treatment arm developed parkinsonism. Both putamen and caudate uptake decreased over time in the control arm. In the treatment arm, only the putamen uptake decreased over time, whereas caudate uptake remained stable. GLM analysis demonstrated an effect of treatment on the I-FP-CIT-SPECT uptake change, with a significant interaction between the effect of group, time, and regions (p = 0.004).
CONCLUSIONS
A 30-months neuroprotection study for prodromal synucleinopathy is feasible, using iRBD as the target population and I-FP-CIT-SPECT as a biomarker of disease progression.
Topics: Aged; Female; Humans; Male; Middle Aged; Neuroprotection; Putamen; REM Sleep Behavior Disorder; Synucleinopathies; Tomography, Emission-Computed, Single-Photon
PubMed: 33275819
DOI: 10.1111/ene.14664 -
Journal of Neuroscience Research Jul 2022Complex regional pain syndrome (CRPS) is a painful condition commonly accompanied by movement disturbances and often affects the upper limbs. The basal ganglia motor...
Complex regional pain syndrome (CRPS) is a painful condition commonly accompanied by movement disturbances and often affects the upper limbs. The basal ganglia motor loop is central to movement, however, non-motor basal ganglia loops are involved in pain, sensory integration, visual processing, cognition, and emotion. Systematic evaluation of each basal ganglia functional loop and its relation to motor and non-motor disturbances in CRPS has not been investigated. We recruited 15 upper limb CRPS and 45 matched healthy control subjects. Using functional magnetic resonance imaging, infraslow oscillations (ISO) and resting-state functional connectivity in motor and non-motor basal ganglia loops were investigated using putamen and caudate seeds. Compared to controls, CRPS subjects displayed increased ISO power in the putamen contralateral to the CRPS affected limb, specifically, in contralateral putamen areas representing the supplementary motor area hand, motor hand, and motor tongue. Furthermore, compared to controls, CRPS subjects displayed increased resting connectivity between these putaminal areas as well as from the caudate body to cortical areas such as the primary motor cortex, supplementary and cingulate motor areas, parietal association areas, and the orbitofrontal cortex. These findings demonstrate changes in basal ganglia loop function in CRPS subjects and may underpin motor disturbances of CRPS.
Topics: Basal Ganglia; Complex Regional Pain Syndromes; Hand; Humans; Magnetic Resonance Imaging; Movement
PubMed: 35441738
DOI: 10.1002/jnr.25057 -
Social Cognitive and Affective... Aug 2019Previous neuroimaging studies have suggested that the neural bases of trait emotional intelligence (TEI) lie in the social cognition network (SCN) and the somatic marker...
Previous neuroimaging studies have suggested that the neural bases of trait emotional intelligence (TEI) lie in the social cognition network (SCN) and the somatic marker circuitry (SMC). The current study was the first to investigate the associations of total TEI factors and subfactors with mean diffusivity (MD) of these networks as well as regional MD of the dopaminergic system (MDDS). We found that TEI intrapersonal factor score and total TEI score were negatively correlated with regional MDDS in the vicinity of the right putamen and right pallidum and that TEI intrapersonal factor score was negatively correlated with MD values of the fusiform gyrus. Total TEI score and TEI factor scores were positively correlated with MD values of various areas within or adjacent to SCN components, SMC structures and the lateral prefrontal cortex (LPFC). Our MD findings demonstrated the importance of the dopaminergic system to TEI and implicate the SCN, SMC and LPFC in TEI. Future studies are required to investigate the implications of positive and negative associations with MD values.
Topics: Brain; Cognition; Diffusion Magnetic Resonance Imaging; Emotional Intelligence; Female; Humans; Male; Neuroimaging; Prefrontal Cortex; Putamen; Social Behavior
PubMed: 31593230
DOI: 10.1093/scan/nsz059 -
Tremor and Other Hyperkinetic Movements... 2022Chorea can be due to a large number of etiologies. Unilateral chorea is classically related to a contralateral structural lesion, e.g. of the putamen or subthalamic... (Review)
Review
BACKGROUND
Chorea can be due to a large number of etiologies. Unilateral chorea is classically related to a contralateral structural lesion, e.g. of the putamen or subthalamic nucleus, however, based upon personal impressions, we have observed that systemic disease, in particular metabolic or autoimmune conditions, can also lead to a unilateral or markedly asymmetric presentations. We sought to investigate this impression by reviewing the literature.
METHODS
A PubMed search was conducted using the terms asymmetric" AND "chorea" OR "hemichorea" OR "unilateral" AND "chorea" OR "monochorea" OR "right greater than left" AND "chorea" OR "left greater than right" AND "chorea" OR "right more than left" AND "chorea" OR "left more than right" AND "chorea" as well as "hemiballismus" NOT "stroke" NOT "infarct" NOT "dyskinesia. A total of 243 sources were felt to meet criteria and were reviewed.
RESULTS
The most common etiology of reported hemi- or asymmetric chorea was diabetic non-ketotic hyperglycemic hemichorea/hemiballismus. Other common diagnoses were Sydenham's disease, antiphospholipid syndrome and drug-induced chorea. The vast majority of patients with hemi- or asymmetric chorea had acquired rather than genetic, degenerative or congenital causes.
CONCLUSION
Despite the potential limitations of our literature review, the evidence presented here supports the observation that the vast majority of asymmetric or unilateral chorea presentations are due to acquired causes, and in this situation an exhaustive search for reversible etiology should be undertaken. However, presentation with symmetric, generalized chorea does not exclude reversible causes, and investigations should address these in addition to genetic and neurodegenerative etiologies.
Topics: Chorea; Dyskinesias; Humans; Movement Disorders; Putamen; Subthalamic Nucleus
PubMed: 35136702
DOI: 10.5334/tohm.675 -
The Journal of Comparative Neurology May 2023An important factor that can modulate neuron properties is sex-specific hormone fluctuations, including the human menstrual cycle and rat estrous cycle in adult females....
An important factor that can modulate neuron properties is sex-specific hormone fluctuations, including the human menstrual cycle and rat estrous cycle in adult females. Considering the striatal brain regions, the nucleus accumbens (NAc) core, NAc shell, and caudate-putamen (CPu), the estrous cycle has previously been shown to impact relevant behaviors and disorders, neuromodulator action, and medium spiny neuron (MSN) electrophysiology. Whether the estrous cycle impacts MSN dendritic spine attributes has not yet been examined, even though MSN spines and glutamatergic synapse properties are sensitive to exogenously applied estradiol. Thus, we hypothesized that MSN dendritic spine attributes would differ by estrous cycle phase. To test this hypothesis, brains from adult male rats and female rats in diestrus, proestrus AM, proestrus PM, and estrus were processed for Rapid Golgi-Cox staining. MSN dendritic spine density, size, and type were analyzed in the NAc core, NAc shell, and CPu. Overall spine size differed across estrous cycle phases in female NAc core and NAc shell, and spine length differed across estrous cycle phase in NAc shell and CPu. Consistent with previous work, dendritic spine density was increased in the NAc core compared to the NAc shell and CPu, independent of sex and estrous cycle. Spine attributes in all striatal regions did not differ by sex when estrous cycle was disregarded. These results indicate, for the first time, that estrous cycle phase impacts dendritic spine plasticity in striatal regions, providing a neuroanatomical avenue by which sex-specific hormone fluctuations can impact striatal function and disorders.
Topics: Humans; Rats; Female; Male; Animals; Nucleus Accumbens; Dendritic Spines; Rats, Sprague-Dawley; Putamen; Estrous Cycle; Estradiol
PubMed: 36756791
DOI: 10.1002/cne.25460 -
Neuropsychologia Feb 2020Episodic future thinking (EFT), the mental ability of projecting oneself into the future to pre-experience an event, has strong adaptive value for allowing people to...
Episodic future thinking (EFT), the mental ability of projecting oneself into the future to pre-experience an event, has strong adaptive value for allowing people to consider potential consequences before taking actions. EFT includes two important components: the ability to construct detailed and vivid scenes of future events to achieve a goal (measured here by the EFT-sensory perceptual qualities scale) and the ability to subjectively experience "mental time travel" in which the person feels oneself to be in the future (measured here by the EFT-Autonoetic consciousness scale). However, little is known about the neuroanatomical structures of EFT. To shed light on this question, we employed voxel-based morphometry (VBM) to investigate the neural substrates underlying EFT. In Sample 1 (135 participants), EFT-sensory perceptual qualities was positively correlated with the gray matter (GM) volume of the hippocampus and putamen. EFT-Autonoetic consciousness was positively correlated with GM volume of the insula and amygdala, and negatively correlated with GM volumes of the medial frontal gyrus. The verification results from Sample 2 (59 participants) found that EFT-sensory perceptual qualities can be predicted by the GM volumes of the hippocampus and putamen, and EFT-Autonoetic consciousness can be predicted by the GM volumes of insula and amygdala. The present findings suggest that the hippocampus, putamen, and amygdala and insula are key regions for scene construction, goal-directed processing, and emotion respectively, and play important roles in the underlying structural neural substrates of EFT.
Topics: Adult; Amygdala; Cerebral Cortex; Consciousness; Female; Goals; Hippocampus; Humans; Magnetic Resonance Imaging; Male; Neuroimaging; Perception; Putamen; Self Concept; Thinking; Young Adult
PubMed: 31715196
DOI: 10.1016/j.neuropsychologia.2019.107255