Search results for "BASAL GANGLIA"
showing 10 items of 110 documents
Association Between Atrophy of the Caudate Nuclei, Global Brain Atrophy, Cerebral Small Vessel Disease and Mild Parkinsonian Signs in Neurologically …
2017
Background: Mild Parkinsonian signs (MPS) are commonly seen in aging, and have been related to cerebral Small Vessel Diseases (SVD) with no univocal results. Objective: The aim of this study was to investigate the cross-sectional relation between MPS and White Matter Hyperintensities (WMH), lacunes, caudate atrophy, and global cerebral atrophy in a large cohort of Neurologically and Cognitively Healthy (NCH) aging individuals. Method: 1,219 NCH individuals were included in the analysis, and underwent standard brain MRI. The items of the motor section of the Unified Parkinson’s Disease Rating Scale were used to evaluate tremor, rigidity, bradykinesia, and gait/balance/axial dysfunction. Cau…
Chemoarchitecture and afferent connections of the "olfactostriatum": a specialized vomeronasal structure within the basal ganglia of snakes.
2004
The olfactostriatum, a portion of the striatal complex of snakes, is the major tertiary vomeronasal structure in the ophidian brain, receiving substantial afferents from the nucleus sphericus, the primary target of accessory olfactory bulb efferents. In the present study, we have characterized the olfactostriatum of garter snakes (Thamnophis sirtalis) on the basis of chemoarchitecture (distribution of serotonin, neuropeptide Y and tyrosine hydroxylase) and hodology (afferent connections). The olfactostriatum is densely immunoreactive for serotonin and neuropeptide Y and shows moderate-to-weak immunoreactivity for tyrosine hydroxylase. In addition to afferents from the nucleus sphericus, the…
Distinct patterns of Fos immunoreactivity in striatum and hippocampus induced by different kinds of novelty in mice.
2010
In this study the immediate-early gene Fos was used to investigate the response to different novel stimuli in a wide array of brain regions including the hippocampus, the rhinal cortex, the frontal cortex and different components of the striatal complex. Independent groups of CD-1 mice were exposed to three different novelty conditions: (1) novel environment (empty open field); (2) complex novel environment (i.e. open field containing objects); and (3) identity-based detection of novel objects. We observed that a complex novel environment and a knowledge-based novelty modulated Fos levels in both the dorsal and the ventral components of the striatum, while Fos immunoreactivity in the medial…
Subthalamic deep brain stimulation improves time perception in Parkinson's disease.
2004
Alterations in temporal estimation have been observed in Parkinson's disease (PD) and have been associated with dopaminergic dysfunction. To investigate whether deep brain stimulation might reverse these abnormalities in PD, patients treated with electrode implantation for subthalamic deep brain stimulation were required to reproduce time intervals in different experimental conditions (off deep brain stimulation/off therapy, on deep brain stimulation/off therapy, on therapy/off deep brain stimulation). Patients treated with deep brain stimulation in off deep brain stimulation/off therapy displayed the anomalous pattern of responses typically observed in PD. When subthalamic deep brain stimu…
Modifications of head turning and circling movement following sulpiride microinjections into nucleus accumbens in the rat
1995
The aim of this study was to determine whether a relationship exists between nucleus accumbens D2 receptors, circling behavior, and its first stage, the head turning. Rats were unilaterally lesioned in the substantia nigra with 6-hydroxydopamine and afterward treated with d-amphetamine IP following bilateral intraaccumbens microinjections (1, 5, 10 micrograms/0.5 microliters) of sulpiride, a D2 receptor antagonist. Computer-assisted video analysis allowed the study of some parameters (number of turns, type of turn, head turning duration, degree and speed) characterizing rotatory activity. Sulpiride microinfusion resulted in a dose-dependent decrease of the number of turns and head rotation …
Effects of scopolamine on dopamine neurons in the substantia nigra : role of the pedunculopontine tegmental nucleus
2009
Previous neurochemical and behavioral studies suggest that muscarinic receptor antagonism has an excitatory effect on the nigrostriatal dopamine (DA) system. Using in vivo extracellular single unit recording, this study examined whether blockade of the muscarinic receptor by scopolamine alters the firing properties of DA neurons in the substantia nigra (SN). Scopolamine was administered either systemically or locally to DA neurons using microiontophoresis. Surprisingly, scopolamine did not cause any significant change in either the firing rate or pattern of the spontaneously active DA neurons. However, systemic injection of scopolamine significantly increased the number of active DA neurons…
Analysis of the impact of a cognitive task on the posture of elderly subjects with depression compared with healthy elderly subjects
2016
International audience; Objective: While previous studies have demonstrated that depressive elderly subjects (DES) experience difficulties in the processing of simultaneous cognitive tasks, few have examined the coupling of cognitive tasks with seemingly 'automatic' tasks, such as standing upright. Current patient management focuses on pharmacological treatments and cognitive-behavioral therapies.Methods: Healthy elderly (HES) and non-treated DES were included. Postural sway in DES was compared with that in HES while in single-task and dual-task conditions. The single-task consisted of standing upright. For the dual-task, the subjects recalled various items from memory or counted while stan…
Assessment of Susceptibility Risk Factors for ADHD in Imaging Genetic Studies
2019
Objective: ADHD consists of a count of symptoms that often presents heterogeneity due to overdispersion and excess of zeros. Statistical inference is usually based on a dichotomous outcome that is underpowered. The main goal of this study was to determine a suited probability distribution to analyze ADHD symptoms in Imaging Genetic studies. Method: We used two independent population samples of children to evaluate the consistency of the standard probability distributions based on count data for describing ADHD symptoms. Results: We showed that the zero-inflated negative binomial (ZINB) distribution provided the best power for modeling ADHD symptoms. ZINB reveals a genetic variant, rs273342…
Efferent connections of the "olfactostriatum": a specialized vomeronasal structure within the basal ganglia of snakes.
2005
Abstract The olfactostriatum is a portion of the basal ganglia of snakes that receives substantial vomeronasal afferents through projections from the nucleus sphericus. In a preceding article, the olfactostriatum of garter snakes (Thamnophis sirtalis) was characterized on the basis of chemoarchitecture (distribution of serotonin, neuropeptide Y and tyrosine hydroxylase) and pattern of afferent connections [Martinez-Marcos, A., Ubeda-Banon, I., Lanuza, E., Halpern, M., 2005. Chemoarchitecture and afferent connections of the “olfactostriatum”: a specialized vomeronasal structure within the basal ganglia of snakes. J. Chem. Neuroanat. 29, 49–69]. In the present study, its efferent connections …
The discharge of subthalamic neurons is modulated by inhibiting the nitric oxide synthase in the rat.
2005
The effects induced on the discharge of subthalamic spontaneously active neurons by inhibiting the enzyme nitric oxide synthase was studied in two groups of urethane-anesthetized rats. In the first group of animals (n = 10), the activity of subthalamic single units was recorded before and after the systemic administration of 7-nitro-indazole (7-NI, 50 mg/kg i.p.), a selective inhibitor of neuronal nitric oxide synthase. In the second group of rats (n = 15), Nomega-nitro-L-arginine methyl ester (L-NAME), another inhibitor of nitric oxide synthase, was iontophoretically administered while performing single unit extracellular recordings. The activity of most tested spontaneously discharging ne…