Search results for "BASAL GANGLIA"

Understanding the Role of Sensorimotor Beta Oscillations

2021

Beta oscillations have been predominantly observed in sensorimotor cortices and basal\ud ganglia structures and they are thought to be involved in somatosensory processing\ud and motor control. Although beta activity is a distinct feature of healthy and pathological\ud sensorimotor processing, the role of this rhythm is still under debate. Here we review\ud recent findings about the role of beta oscillations during experimental manipulations (i.e.,\ud drugs and brain stimulation) and their alteration in aging and pathology. We show how\ud beta changes when learning new motor skills and its potential to integrate sensory input\ud with prior contextual knowledge. We conclude by discussing a n…

2002

Previous observations have suggested a role for nitric oxide in the activity of the globus pallidus, but this functional involvement has not yet been tested in vivo. The extracellular activity of single units of the globus pallidus was recorded, and neuronal nitric oxide synthase was inhibited by systemically administering 7-nitro-indazole to a group of anaesthetised rats. Forty-five per cent of cells responded with a decrease in the firing rate. In another group of rats, the microiontophoretic administration of 3-morpholino-sydnonimin-hydrocloride (a nitric oxide donor) induced an increase in neuronal firing rate (24/28 cells), whereas the administration of Nω-nitro-L-arginine methyl ester…

Memory for time intervals is impaired in left hemi-Parkinson patients.

2004

The basal ganglia have been proposed as one of the neural correlates of timekeeping functions. Both encoding and memory retrieval components for time perception are impaired in Parkinson's disease (PD). The aim of our study was to investigate in hemi-Parkinsonian patients the existence of a specific alteration in memory for time depending on the affected side, to better understand the contribution of the left or right basal ganglia circuits in different components of time perception. Right and left hemi-PD patients performed a time reproduction task in which they were required to reproduce in the same session short (5 s) and long (15 s) time intervals, in off- and on-therapy condition. Whil…

Serotonin modulation of the basal ganglia circuitry: therapeutic implication for Parkinson's disease and other motor disorders

2008

Several recent studies have emphasized a crucial role for the interactions between serotonergic and dopaminergic systems in movement control and the pathophysiology of basal ganglia. These observations are supported by anatomical evidence demonstrating large serotonergic innervation of all the basal ganglia nuclei. In fact, serotonergic terminals have been reported to make synaptic contacts with both substantia nigra dopamine-containing neurons and their terminal areas such as the striatum, the globus pallidus and the subthalamus. These brain areas contain a high concentration of serotonin (5-HT), with the substantia nigra pars reticulata receiving the greatest input. In this chapter, the d…

Prediction error signal correlates with fluid intelligenceand dopamine synthesis across the lifespan

2011

IntroductionFluid intelligence expresses the capacity for interpretation of novel stimuli and flexible behavioral adaptation to such cues. Phasic dopamine firing closely matches a temporal difference prediction error (PE) signal important for learning and rapid behavioral adaptation. Both fluid intelligence and dopaminergic neurotransmission decline with age. So far, no study investigated the relationship between fluid IQ, PE signal and direct measures of dopaminergic neurotransmission. Here we used a multimodal imaging approach that combines positron emission tomography and functional magnetic resonance imaging.MethodsA group of healthy controls was investigated with both 6-[18F]FluoroDOPA…

Femoral neck’s fracture in Fahr’s Syndrome: case report

2016

Fahr's syndrome, also known as "Bilateral Striopallidodentate Calcinosis" (BSPDC) primitive, is a rare neurological disease characterized by the presence of idiopathic, bilateral, symmetrical and abnormal deposition of calcium in areas of the brain that control movements including the basal ganglia, dentate nuclei of the cerebellum, nuclei of thalamus and semi-oval center. We describe a case of a 76-year-old male patient underwent reduction and fixation of a subtrochanteric fracture with intramedullary nail. During post-operative rehabilitation therapists's patient management was difficult due to obvious extrapyramidal symptoms characterized by dysarthria, rigidity, bradykinesia, postural i…

Modifications induced on the amygdaloid paroxysmal activity by entopeduncolar or nigral injection of kainic acid, in the cat.

1983

Entopeduncolar or nigral injection of kainic acid determines an early decrease of the evoked amygdaloid paroxysmal activity and a later increase of the after discharge duration. This biphasic effect is likely due to the structural analogy of the drug with monosodium glutamate, a neuroexcitant amino acid. The data suggest that the basal ganglia exert a tonic control on the amygdaloid activity.

Acute reversible parkinsonism in a diabetic-uremic patient.

2005

Acute movement disorders with basal ganglia lesions have been recently described in diabetic-uremic patients of Asian descent. The process is often reversible, with a favourable clinical outcome. Metabolic (i.e. uremic toxins) and microangiopathic changes have been suggested to be involved in its pathophysiology, even though racial and/or genetic factors might play a role too. In this report, we present a Caucasian diabetic patient with a long-lasting mild uremia in which acute parkinsonism occurred after a steep and unexpected increase of the serum creatinine. The follow-up demonstrated a significant improvement of the neurological signs and symptoms, the creatinine level lowered close to …

Regulation of NT Receptors after Chronic Treatment with Typical and Atypical Neuroleptic Drugs

1991

Neurotensin is a tridecapeptide, which produces central effects such as hypotension, hypothermia, muscle relaxation, analgesia, antinociception, and reduces locomotor activity (Nemeroff et al., 1977). In the recent years, several lines of evidences indicated the great importance of the dopamine (DA)- neurotensin (NT) interaction taking place mostly in the mesolimbocortical areas, both at cell bodies (A10 DA-ergic group located in the ventral tegmental area -VTA-) and nerve terminal level (cerebral cortex, n. accumbens, olfactory tubercle, ventral n. caudato-putamen) (Quirion, 1983; Nemeroff, et al., 1984; Nemeroff, 1986). Immunocytochemical data indicated the presence of NT-like immunoreact…

Transcranial direct current stimulation for treatment of freezing of gait: A cross-over study

2014

Background and objective Progression of Parkinson's disease (PD) is frequently characterized by the occurrence of freezing of gait (FOG) representing a disabling motor complication. We aim to investigate safety and efficacy of transcranial direct current stimulation of the primary motor cortex of PD patients with FOG. Methods In this cross-over, double-blind, sham-controlled study, 10 PD patients with FOG persisting in “on” state underwent anodal and sham direct current stimulation for 5 consecutive days. Clinical assessment over a 1-month period was performed. Results A significant improvement of gait, as assessed by the Stand Walk Sit test, with reduction in number and duration of FOG epi…