Search results for "Thalamu"
showing 10 items of 280 documents
Chicken adaptive response to low energy diet: main role of the hypothalamic lipid metabolism revealed by a phenotypic and multi-tissue transcriptomic…
2019
AbstractBackgroundProduction conditions of layer chicken can vary in terms of temperature or diet energy content compared to the controlled environment where pure-bred selection is undertaken. The aim of this study was to better understand the long-term effects of a 15%-energy depleted diet on egg-production, energy homeostasis and metabolism via a multi-tissue transcriptomic analysis. Study was designed to compare effects of the nutritional intervention in two layer chicken lines divergently selected for residual feed intake.ResultsChicken adapted to the diet in terms of production by significantly increasing their feed intake and decreasing their body weight and body fat composition, whil…
Glucose but Not Protein or Fat Load Amplifies the Cortisol Response to Psychosocial Stress
2002
We previously reported that glucose intake amplifies cortisol response to psychosocial stress and smoking in healthy young men, while low blood glucose levels prevented the stress-induced activation of the hypothalamus pituitary adrenal (HPA) axis. However, it remains unknown whether this modulation is specific for glucose load or a more common effect of energy availability. To elucidate this question, 37 healthy men, who fasted for at least 8 h before the experiment, were randomly assigned to four experimental groups, who received glucose (n = 8), protein (n = 10), fat (n = 10), and water (n = 9), one h before their exposure to the Trier Social Stress Test (TSST). Blood glucose levels were…
Thalamic infarctions cause side-specific suppression of vestibular cortex activations.
2005
H2O15-PET was performed during caloric vestibular stimulation of the right and left external ears in eight right-handed patients with acute unilateral infarctions or haemorrhages of the posterolateral thalamus (four right, four left). The posterolateral thalamus is the relay station for ipsi- and contralateral ascending vestibular input to the multiple multisensory vestibular cortex areas. The aim of this study was to evaluate the differential effects of unilateral vestibular thalamic lesions on thalamo-cortical projections, right hemispheric dominance and reciprocal inhibitory visual-vestibular interaction, as well as perceptual and ocular motor consequences during caloric irrigation. The …
Breakdown of Thalamo-Cortical Connectivity Precedes Spike Generation in Focal Epilepsies
2017
Electroencephalography (EEG) spikes and focal epileptic seizures are generated in circumscribed cerebral networks that have been insufficiently described. For precise time and spatial domain network characterization, we applied in patients with focal epilepsy dense array 256-channel EEG recordings with causal connectivity estimation by using time-resolved partial directed coherence and 3T-magnetic resonance imaging-derived cortical and thalamus integrity reconstruction. Before spike generation, significant theta and alpha bands driven information flows alterations were noted from both temporal and frontal lobes to the thalamus and from the thalamus to the frontal lobe. Medial dorsal and ven…
Eyes open and eyes closed as rest conditions: impact on brain activation patterns
2003
The patterns of associated brain activations during eyes-open and eyes-closed states in complete darkness considerably differ in fMRI. An "interoceptive" state with the eyes closed is characterized by visual cortex activation, while an "exteroceptive" state with the eyes open is characterized by ocular motor system activity. The impact of the chosen rest condition (eyes open or eyes closed in complete darkness) on the pattern of brain activations during visual stimulation was evaluated in 14 healthy volunteers. During fixation or dim light room illumination, the activation of the visual cortex was larger with the eyes-open rest condition than with the eyes-closed rest condition; however, ac…
The role of the thalamus in amnesia: a tractography, high-resolution MRI and neuropsychological study.
2008
Although it is well established that thalamic lesions may lead to profound amnesia, the precise contribution of thalamic sub-regions to memory remains unclear. In an influential article Aggleton and Brown proposed that recognition memory depends on two processes supported by distinct thalamic and cortical structures. Familiarity is mediated by the mediodorsal (MD) thalamic nucleus and the entorhinal/ perirhinal cortex. Recollection ismediated by the anterior thalamic nucleus (AN), the mamillothalamic tract (MTT) and the hippocampus. The authors also suggested that the lateral dorsal nucleus (LD) may contribute to the thalamic/hippocampus system, thereby implying that the LD may play a role …
High opiate receptor binding potential in the human lateral pain system
2005
To determine how opiate receptor distribution is co-localized with the distribution of nociceptive areas in the human brain, eleven male healthy volunteers underwent one PET scan with the subtype-nonselective opioidergic radioligand [(18)F]fluoroethyl-diprenorphine under resting conditions. The binding potential (BP), a parameter for the regional cerebral opioid receptor availability, was computed using the occipital cortex as reference region. The following regions of interest (ROIs) were defined on individual MR images: thalamus, sensory motor strip (SI/MI area), frontal operculum, parietal operculum, anterior insular cortex, posterior insular cortex, anterior cingulate cortex (ACC; peri-…
Hypothalamic-pituitary-thyroid axis in acromegaly
1983
To evaluate the hypothalamic-pituitary-thyroid axis in acromegaly, total and free thyroid hormones and TSH response to TRH were determined in 36 acromegalic patients. In 10 patients, rT3 and thyroxine binding globulin (TBG) were also assayed by radioimmunoassay. In 15 patients the TSH response to TRH was also studied after medical or surgical therapy of the acromegaly. In 34 patients total thyroid hormones were in the normal range whereas two patients had low serum levels of free thyroid hormones. Thirty-two of the acromegalic patients were euthyroid. However, only 43.7% of the euthyroid patients had a normal TSH response to TRH. Nine patients had a reduced TSH rise after TRH, whereas in 4 …
Impaired control of an action after supplementary motor area lesion: A case study
2000
The kinematics of the action formed by reaching-grasping an object and placing it on a second target was studied in a patient who suffered from an acute vascular left brain lesion, which affected the Supplementary Motor Area proper (SMA-proper) (Matelli M, Luppino G. Thalamic input to mesial and superior area 6 in the macaque monkey. Journal of Comparative Neurology 1996;372:59-87, Matelli M, Luppino G, Fogassi L, Rizzolatti G. Thalamic input to inferior area 6 and area 4 in the macaque monkey. Journal of Comparative Neurology 1989;280:468-488), and in five healthy control subjects. The reach kinematics of the controls was affected by the positions of both the reaching-grasping and the plac…
Cerebral activation in patients with somatoform pain disorder exposed to pain and stress: an fMRI study.
2006
Patients with somatoform pain disorders are supposed to suffer from an early acquired defect in stress regulation. In order to look for common alterations of the pain- and stress-responsive cortical areas, we prospectively recorded cerebral activations induced by pin-prick pain, by cognitive stress and emotional stress using functional magnetic resonance imaging (fMRI) in a group of 17 patients and an age-matched control group. In addition, the hippocampal volumes of both groups were measured. Patients showed increased activations of the known pain-processing areas (thalamus, basal ganglia, operculo-insular cortex), but also of some prefrontal, temporal and parietal regions during first pai…