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PubMed1992

Expression of c-fos-like immunoreactivity in brainstem after meningeal irritation by blood in the subarachnoid space.

The expression of c-fos protein was examined by immunohistochemistry in serial sections of brainstem following the instillation of either autologous arterial blood (0.3 ml) or mock cerebrospinal fluid (0.3 ml) through a catheter placed in the cisterna magna, or following catheter placement alone in pentobarbital-anesthetized Sprague-Dawley rats. After injection, blood was distributed within the subarachnoid space surrounding the brainstem and in the region of the circle of Willis. c-fos protein-like immunoreactivity was present at 1 h, peaked at 2 h and decreased by 8 h. At 2 h, immunoreactivity was strongly expressed within trigeminal nucleus caudalis (lamina I, IIo), as well as within nucleus of the solitary tract, area postrema, ependyma, pia mater and arachnoid in every animal. Moderate labeling was found in parabrachial nucleus, medullary lateral reticular nucleus and central gray. Sparse labeling was present in trigeminal nucleus caudalis (lamina III-V) and trigeminal nucleus interpolaris; few or no labeled cells were detected in other parts of the trigeminal nuclear complex, thalamus, cerebral cortex, cerebellar cortex or trigeminal ganglion. The number of positive cells was not related to the volume of injectate but was related to the amount of injected blood. The density of cell labeling evoked by injecting mock cerebrospinal fluid or after catheter placement was markedly lower than after blood in all brainstem areas. The number of labeled cells was greatly reduced within trigeminal nuclear complex, parabrachial nucleus and medullary lateral reticular nucleus, but not within the nucleus of the solitary tract, area postrema or ependyma when blood was injected into adult animals in which unmyelinated C-fibers were destroyed by neonatal capsaicin treatment. Similar results were obtained after blood was instilled into the cisterna magna of rats in which meningeal afferents were chronically sectioned at the ethmoidal foramen bilaterally. We conclude that blood in the subarachnoid space is an effective stimulus for activating c-fos expression within subpopulations of brainstem neurons. Activation within trigeminal nucleus caudalis is mediated in large part by excitation of small-caliber meningeal afferents (trigeminovascular fibers), whereas c-fos expression within nucleus of the solitary tract and area postrema may reflect direct stimulation of blood or blood products, or possibly the response to autonomic activation from noxious stimulation.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

PubMedDate not supplied

Ca2+/calmodulin-dependent protein kinase II in the rat cerebellum: an immunohistochemical study with monoclonal antibodies specific to either alpha or beta subunit.

Monoclonal antibodies specific to either alpha or beta subunit of Ca2+/calmodulin-dependent protein kinase II (CaM kinase II) of the rat brain were produced and the distribution of each subunit in the rat cerebellum was examined immunohistochemically. Each antibody detected solely the corresponding subunit in immunoblot analysis of crude homogenates of the rat forebrain and cerebellum, and purified CaM kinase II from the rat forebrain. Immunoreactivity for alpha subunit was present selectively in Purkinje cells: perikarya, dendrites with their spines, axons and their terminal-like structures in the cerebellar cortex, cerebellar nuclei and lateral vestibular nucleus. Many of these alpha subunit-immunoreactive axons from the cerebellum were traced only through the inferior cerebellar peduncle. beta Subunit was detected in perikarya and dendrites of a limited number of Purkinje cells, many granule cells and neurons in the cerebellar nuclei. Thus, different distributions of alpha and beta subunits of CaM kinase II in the cerebellum were demonstrated.

Animals↗

PubMed1998

Correlation between potentiation of AP1 DNA binding and expression of c-Fos in association with phosphorylation of CREB at serine133 in thalamus of gerbils with ischemia.

Protein biosynthesis is mainly under the control at the level of gene transcription in eukaryotes. Transcription factors are nuclear proteins with abilities to modulate the activity of RNA polymerase II which is responsible for the formation of messenger RNA from double stranded DNA in the cell nuclei. Binding of a radiolabeled oligonucleotide probe for the transcription factor activator protein-1 (AP1) was transiently potentiated 1 to 6 h after the recirculation of blood supply in the thalamus and striatum, but not in the entorhinal cortex, olfactory bulb, frontal cortex, cerebellar cortex and medulla-pons, in gerbils with transient global forebrain ischemia for 5 min, in addition to the hippocampal subregions. The ischemic insult not only increased the immunoreactivity with an antibody against cyclic AMP response element binding protein (CREB) phosphorylated at serine133, but also induced the expression of both c-Jun and c-Fos family proteins 3 h after the recirculation in the thalamus. Limited proteolysis by Staphylococcus aureus (S. aureus) V8 protease revealed the expression of different partner proteins of AP1 in response to ischemic signals in the thalamus. Moreover, ischemia for 2 min led to more prolonged elevation of AP1 binding in the thalamus at least up to 12 h after the reperfusion than that seen with ischemia for 5 min. These results suggest that potentiation of AP1 DNA binding may at least in part involve mechanisms associated with the expression of c-Fos protein through phosphorylation of CREB at serine133 in the thalamus of gerbils with ischemia.

Amino Acid Sequence↗

PubMed2002

Maternal deprivation increases cell death in the infant rat brain.

Prolonged separation from the mother can interfere with normal growth and development and is a significant risk factor for adult psychopathology. In rodents, separation of a pup from its mother increases the behavioral and endocrine responses to stress for the lifetime of the animal. Here we investigated whether maternal deprivation could affect brain development of infant rats via changes in the rate of cell death as measured by labeling the 3' end of DNA fragments using terminal transferase (ApopTag). At postnatal day 12 (P12), the number of cells undergoing cell death approximately doubled in the cerebral cortex, cerebellar cortex and in several white matter tracts following 24 h of maternal deprivation. Deprivation strongly increased the number of ApopTag-labeled cells at P6 but not at P20. Stroking the infant rats only partially reversed the effects of maternal deprivation. Increased cell death in white matter tracts correlated with an induction of nerve growth factor which has been previously associated with oligodendrocyte cell death. Cell birth was either unchanged or decreased in response to deprivation. These results indicate that maternal deprivation can alter normal brain development by increasing cell death of neurons and glia, and provides a potential mechanism by which early environmental stressors may influence subsequent behavior.

Adrenocorticotropic Hormone↗

PubMed1985

Cystathionine disappearance with neuronal loss: a possible neuronal marker.

Cystathionine is an important intermediate in the transsulfuration pathway of methionine catabolism and is normally present in high concentration in the human CNS. We have measured the concentration of cystathionine, other amino acids, and brain proteins in the cerebral cortex, cerebellar cortex and spinal cord of two cases with ceroid lipofuscinosis. Neuropathological and biochemical studies of Case 1, at an advanced stage, Case 2, at an early stage, and five controls were correlated with clinical and neurological findings. The concentration of an unidentified 54,000 Dalton protein was greatly increased in Case 1 as observed by 2-D gel electrophoresis. Neurons and cystathionine were almost totally absent from the cortex and cerebellum of Case 1, while they were slightly reduced in Case 2, in comparison to control brains. These studies suggest that cystathionine may be specifically located within neurons. We present for the first time the observation that there was a strikingly low brain concentration of cystathionine, a potential neuronal marker, in an advanced stage of a neurodegenerative process.

Adolescent↗

PubMed1985

Neurochemical abnormalities in brains of renal failure patients treated by repeated hemodialysis.

We examined autopsied brain from 10 patients with end-stage renal failure who had undergone repeated hemodialysis. Eight had classic symptoms, and two had suggestive symptoms of dialysis encephalopathy. Findings were compared with those in autopsied brain from control adults who had never been hemodialyzed. Mean gamma-aminobutyric acid (GABA) contents were significantly reduced in frontal and occipital cortex, cerebellar cortex, dentate nucleus, caudate nucleus, and medial-dorsal thalamus of the hemodialyzed patients, the reduction being greater than 40% in cerebral cortex and thalamus. Choline acetyltransferase activity was reduced by 25-35% in three cortical regions in the hemodialyzed patients. These two abnormalities were observed in the brain of each hemodialyzed patient, regardless of whether or not the patient died with unequivocal dialysis encephalopathy. Pyridoxal phosphate contents were substantially reduced in brains of the hemodialyzed patients, but metabolites of noradrenaline, 3,4-dihydroxyphenylethylamine (dopamine), and 5-hydroxytryptamine (serotonin) were present in normal amounts. Aluminum levels were abnormally high in frontal cortical gray matter in the hemodialyzed patients. Although this study does not clarify the role played by aluminum toxicity in the pathogenesis of dialysis encephalopathy, the abnormalities we found suggest the need for further neurochemical investigations in this disorder.

Adult↗

PubMed1978

Central actions of benzodiazepines: general introduction.

After a brief review of the characteristic somatic and psychotropic effects of benzodiazepines evidence is presented which supports a specific facilitatory action of these drugs on GABA ergic synapses within the mammalian central nervous system. Benzodiazepines enhance presynaptic inhibition in the spinal cord and dorsal column nuclei as well as postsynaptic inhibition in dorsal column nuclei, hippocampus, hypothalamus, cerebral cortex, cerebellar cortex, which are all examples of recurrent and collateral inhibition mediated by GABA ergic intrinsic neurones. In addition, the compounds also enhance the inhibitory effect of GABA ergic long projection neurones in the substantia nigra and the lateral vestibular nucleus of Deiters. Several problems remain to be solved, such as the exact site at which benzodiazepines initiate their action (pre-synaptically at GABA ergic nerve endings or postsynaptically at the target cells) and the possible existence of endogenous ligands for the benzodiazepine receptor. Some suspected implications which studies on benzodiazepine binding sites could have for a deeper understanding of the mode of action of these drugs are discussed.

Animals↗

PubMed1995

Prompt gamma ray spectrometry for in vivo measurement of boron-10 concentration in rabbit brain tissue.

Boron-10 concentrations in the brain of live rabbits were measured by prompt gamma ray spectrometry at intervals over a 24-hour period. Boron-10 concentrations in the blood and cerebrospinal fluid (CSF) were also measured. Animals were killed at each interval to obtain brain tissues to measure the boron-10 concentration in the brainstem, cerebral cortex, cerebellar cortex, and basal ganglia, as well as the whole brain. Boron-10 concentrations in the live brain did not differ significantly from those measured in whole brain tissue. Boron-10 concentrations in the blood were much higher than in the brain at each interval after injection. These boron-10 concentrations showed a similar pattern of initial rapid decrease, followed by a more gradual decrease. There was little boron-10 present in the CSF. The brainstem contained a significantly larger concentration of boron-10 than the other tissues. Prompt gamma ray spectrometry has the potential for direct measurement of boron-10 concentrations in the brain of patients undergoing boron neutron capture therapy.

Animals↗

PubMed2003

Short communication: Tissue distribution of leptin and leptin receptor mRNA in the bovine.

Detection of leptin and leptin receptor mRNA in various tissues is crucial to an understanding of leptin physiology in dairy cattle. We report here evidence of leptin receptor gene expression in central and peripheral tissues of the bovine by reverse transcription and polymerase chain reaction analysis. Leptin mRNA was detectable in mammary parenchyma and in adipose tissue with similar transcript abundance among the subcutaneous, pericardial, perirenal, and mesenteric adipose depots. The mRNA for the long-form of the leptin receptor, Ob-Rb, was detectable in all four adipose depots, mammary parenchyma, semintendinosus muscle, liver, adrenal cortex, spleen, kidney, testis, mesenteric lymph node, lung, aorta, abomasum, duodenum, jejunum, ileum, hypothalamus, pituitary, brain stem, cerebral cortex, cerebellar cortex, pons, and pineal gland. The mRNA for the short form of the leptin receptor, Ob-Ra, was detectable in the liver, adrenal cortex, spleen, pituitary, and brain stem, but not in the other tissues surveyed. The wide spectrum of tissues expressing the leptin receptor gene reveals that leptin may have multiple physiological functions in the bovine.

Adipose Tissue↗

PubMed1992

[Isolation and analysis of brain-specific sequences from cDNA libraries for various segments of the human brain].

The cDNA libraries in gt10 were constructed from total poly(A)+RNA of human forebrain cortex, cerebellar cortex and medulla oblongata. We selected the clones which gave hybridization signal with brain cDNA only, or gave no signal from these libraries. Expression pattern and structure of two brain-specific clones Hfb1 from forebrain library and Hmob3 from medulla oblongata library were analyzed in detail. Hfb1 hybridized to two different transcripts (about 5 and 2 kb) from frontal cortex, but to a single (longest) from cerebellum. Hfb1 sequence includes 958 nucleotides. Comparison of Hfb1 with the Gene Bank revealed no homology with the sequences present in the Bank. At 3'-end there is poly(A) tail of 24 bases, there is the AATCAA sequence 55 nucleotides upstream which probably serves as a polyadenylation signal. However, AATCAA directs polyadenylation in vitro with very low efficiency. We found no open reading frame in the clone and this is in agreement with the data indicating that brain-specific RNAs has extremely long 3'-untranslated regions. Hmob3 was partially sequences. We compared its primary structure with the sequences from the Gene Bank and revealed no homology. Hmob3 expresses in different parts of human brain and in sceletal muscle but does not express in other tissues.

Base Sequence↗

PubMed1987

Mercury concentrations in the human brain and kidneys in relation to exposure from dental amalgam fillings.

Samples from the central nervous system (occipital lobe cortex, cerebellar cortex and ganglia semilunare) and kidney cortex were collected from autopsies and analysed for total mercury content using neutron activation analyses. Results from 34 individuals showed a statistically significant regression between the number of tooth surfaces containing amalgam and concentration of mercury in the occipital lobe cortex (mean 10.9, range 2.4-28.7 ng Hg/g wet weight). The regression equation y = 7.2 + 0.24x has a 95% confidence interval for the regression coefficient of 0.11-0.37. In 9 cases with suspected alcohol abuse mercury levels in the occipital lobe were, in most cases, somewhat lower than expected based on the regression line. The observations may be explained by an inhibition of oxidation of mercury vapour. The regression between amalgams and mercury levels remained after exclusion of these cases. The kidney cortex from 7 amalgam carriers (mean 433, range 48-810 ng Hg/g wet weight) showed on average a significantly higher mercury level than those of 5 amalgam-free individuals (mean 49, range 21-105 ng Hg/g wet weight). In 6 cases analysis of both inorganic and total mercury was carried out. A high proportion (mean 77% SD 17%) of inorganic mercury was found. It is concluded that the cause of the association between amalgam load and accumulation of mercury in tissues is the release of mercury vapour from amalgam fillings.

Adolescent↗

PubMed1994

Developmental and tissue-specific expression of prosaposin mRNA in murine tissues.

Prosaposin is a multifunctional locus in humans and mice that encodes in tandem and in the same reading frame four glycoprotein activators, or saposins, of lysosomal hydrolases. These ubiquitously expressed glycoproteins and the precursor, prosaposin, have been proposed to function in glycosphingolipid catabolic pathways and glycolipid transport. To characterize the temporal and spatial expression of the prosaposin locus, prenatal and postnatal mouse tissues were screened by in situ hybridization with a mouse antisense riboprobe for prosaposin. Prenatally, prosaposin mRNA was expressed differentially in the placenta and prominently in the decidua basalis and capsularis where expression was gestational age dependent. No other region of high-level expression was detectable in the prenatal mouse. In comparison, high-level differential expression of prosaposin was clearly evident postnatally in a variety of organs, including secretory epithelial cells of the choroid plexus, ependymal lining, upper trachea, esophagus, cortical tubules of the kidney, sertoli cells of the testes and epididymis. Discrete localization of prosaposin mRNA expression was also found in neurons of the cerebral cortex, cerebellar cortex, and lateral columns of the spinal cord as well as in hepatocytes of the mature liver. Very high levels of expression were found in specialized tissues including the Harderian glands and macrophages of lymph nodes, lungs, splenic tissue, and thymus. These studies indicate that the expression of the prosaposin locus, a presumed "housekeeping" gene, is under tissue- and cell-specific differential control. The spatial organization of expression suggests a role for this locus in the expression of glycosphingolipid-storage diseases.

Animals↗

PubMed1975

Cytospectrophotometric studies on the lactate dehydrogenase isoenzymes in functionally different neuron-neuroglia units. I. Optimal procedure conditions and topochemical comparisons in normal mice.

Optimal conditions are described to reveal quantitatively the total activity of lactate dehydrogenase (LDH) and the activity of its H- and M-form in the nervous tissue sections when applying Brody and Engel's tetrazolium method modified by Gerebtzoff. This histochemical reaction has been shown to obey Bouger-Lambert-Beer's law which confirms the possibility of the quantitative determination of the activity of LDH and its isoenzymes by means of cytospectrophotometric method. In the neurons of different areas of the mouse nervous system (cerebral cortex, cerebellar cortex, spinal cord anterior horns, spinal ganglia), both the total LDH activity and the activities of its H- and M-forms were localized in the cytoplasm. Within the limits of the sensitivity and correctness of the cytospectrophotometric method, the ratio of H- to M-forms of LDH did not differ significantly in the majority of the neuron types studied as well as in the neurons as compared with their glial satellite cells.

Animals↗

PubMed1998

Cholinergic neurons of the dorsal pontine tegmentum projecting to the cerebellar vermal cortex of the kitten.

Although the whole cerebellar cortex receives cholinergic afferents, the source of origin of this projection has been clarified only for some corticocerebellar regions. Experiments were performed in kittens to investigate whether the two major cholinergic groups of the brainstem, the pedunculopontine (PPT) and laterodorsal tegmental nuclei (LDT), contribute to the cholinergic innervation of the cerebellar cortex, in particular the vermal cortex. Tegmento-cerebellar projecting neurons were identified by injecting the retrograde tracer rhodamine-labeled latex microspheres in the lobules V to VII of the cerebellar vermis. Subsequently, some of these tegmento-cerebellar neurons were demonstrated to be cholinergic by using the immunohistochemical technique for choline acetyltransferase (ChAT). Only a small portion of the ChAT-positive tegmental neurons projected to the cerebellar vermis. However, among the whole population of the retrogradely labeled tegmental neurons about one third were cholinergic. These cholinergic tegmento-cerebellar neurons were located in the PPT, LDT, and also within the locus coeruleus (LC) complex, where noradrenergic neurons predominate. Since the LC complex sends noradrenergic afferents to the cerebellar cortex, it appears that the dorsal pontine area contributes to the tegmento-cerebellar projections not only with noradrenergic but also with cholinergic afferents. The physiological significance of this cholinergic projection to the cerebellar cortex has been discussed.

Animals↗

PubMed1986

Electron microscopical study of synaptic glomeruli in cerebellum transplanted to the anterior eye chamber.

Fetal cerebellar anlage from rat fetuses of 15-16 operational days were grafted into the anterior chamber of the eye of adult female albino rat recipients. Survival time of the transplants--containing both cerebellar cortex and cerebellar nuclei--was 2 to 2 1/2 months. Electron microscopical (EM) studies of the thin, under-developed granular layer of the laminated cerebellar cortex revealed the presence of well differentiated cerebellar glomeruli, surrounded by granule cell perikarya. As in the normal cerebellar cortex, the central profile of the glomerular complex was the large mossy terminal, containing spheroid synaptic vesicles, and forming synaptic contacts with dendrites and dendritic digits of the granule cells. Golgi cell axonal varicosities, containing ovoid or pleomorphic synaptic vesicles were found also on the periphery of the glomeruli. In addition, in several synaptic glomeruli, a third neuronal element was also observed, containing flat, discoidal vesicles and receiving synaptic contacts from mossy and Golgi axons, but being also presynaptic to granule cell dendrites. It is suggested that all mossy terminals in the cerebellar transplant originate from the cerebellar nucleus. Morphological evidence is also provided that the presynaptic dendrite-like processes--never found in normal cerebellar cortex--are also processes of nuclear neurons.

Animals↗

PubMed1997

Histological changes during development of the cerebellum in the chick embryo exposed to a static magnetic field.

Few studies have been performed to evaluate the ultrastructural changes that exposure to static magnetic fields (SMF) can cause to the processes of cell migration and differentiation in the cerebellum during development. Thus, we have studied the development of the cerebellum in the chick embryo (n = 144) under a uniform SMF (20 mT). All of our observations were done on folium VIc of Larsell's classification. The cerebella of chick embryos, which were exposed solely on day 6 of incubation and sacrificed at day 13 of incubation [short exposure (S)1; n = 24], showed an external granular layer (EGL) that was less dense than the EGL in the control group (n = 24). The molecular layer (ML) exhibited a low number of migratory neuroblastic elements. Moreover, the internal granular layer (IGL) was immature, with the cellular elements less abundant and more dispersed than in controls. In chick embryos exposed on day 6 of incubation and sacrificed at day 17 (S2; n = 24), the outstanding feature was the regeneration of the different layers of the cerebellar cortex. The cerebellar cortex of chick embryos exposed continuously to an identical field from the beginning of the incubation up to day 13 [long exposure (L)1; n = 24] or day 17 (L2; n = 24) of incubation showed a higher number of alterations than that of group S1. Electron microscopy confirmed the findings from light microscopy and, at the same time, showed clear signs of cell degeneration and delay in the process of neuronal differentiation. This was more apparent in groups L1 (100%) and L2 (100%) than in groups S1 (95.4%) and S2 (65.2%). In conclusion, the present study showed that SMF can induce irreversible developmental effects on the processes of cell migration and differentiation of the chick cerebellar cortex.

Animals↗

PubMed1998

Course and targets of the calbindin D-28k subpopulation of primary vestibular afferents.

The subpopulation of primary vestibular afferents (PVA) displaying immunoreactivity for the calcium binding protein Calbindin D-28k (Calb) is constituted of particularly large bipolar neurons in the vestibular ganglion (VG) that innervate the central regions of the vestibular end organs exclusively via calyx endings on type I vestibular hair cells. These large-diameter PVA are characterized by irregular spontaneous discharge patterns and predominantly phasic firing properties with respect to natural vestibular stimulation. The present study describes the complete course and terminations of Calb+ PVA in the cerebellar cortex, the cerebellar (CN) and vestibular nuclei (VN) of the mouse. To eliminate the two sources of Calb+ fibers in the cerebellum, i.e., the Calb+ primary vestibular input and the axons of cerebellar Purkinje cells (PC), in their totality, a unilateral eighth nerve transection was performed in the PC-deficient mutant mice, Purkinje cell degeneration (pcd/pcd) and Lurcher (Lc/+). Neurectomy in these mutants results in a complete ipsilateral loss of Calb+ fibers in the cerebellar cortex, the CN and VN. The Calb+ primary vestibular input on the contralateral side terminates solely in the rostral half of the ventral uvula and in the nodulus of the cerebellar cortex. Calb+ fibers traverse all three subdivisions of the CN, but terminations were found only in the lateral and medial cerebellar nuclei. In the VN, Calb+ PVA terminations were restricted to the superior, the ventral part of the lateral, the lateral portion of the medial, and the inferior vestibular nuclei. Calb + terminals were also present in the small cell group Y and Cajal's interstitial nucleus of the vestibular nerve as well as in defined areas of the reticular formation. All Calb + PVA are strictly unilateral. The results show that the Calb+ subpopulation of VG neurons is the sole source of Calb+ fibers and terminals in the PC-deficient cerebellum and the VN. The central input of this distinct subgroup of PVA is distributed in narrow posterior vermal areas and parts of the CN and VN. The cerebellar mutants, Purkinje cell degeneration and Lurcher, provide excellent tools to selectively investigate the subgroup of Calb+ PVA in the mouse in its entirety.

Animals↗

PubMed2000

Coherence between cerebellar thalamus, cortex and muscle in man: cerebellar thalamus interactions.

Local field potentials (LFPs) were recorded in seven unanaesthetized patients between the four adjacent contacts of a macroelectrode stereotactically implanted for the treatment of tremor. The LFPs were presumed to arise predominantly from the nucleus ventralis intermedius (Vim) of the thalamus, the implantation target. They were recorded simultaneously with the ipsilateral EEG and contralateral EMG during an isometric contraction or at rest. The patients had a history of either isolated tremor (essential tremor, n = 2; benign tremulous Parkinson's disease, n = 1) or tremor with signs of a cerebellar syndrome (multiple sclerosis, n = 3; essential tremor and ataxia, n = 1), although clinical tremor was absent at the time of recording because of a temporary microthalamotomy effect in four patients. In patients with isolated tremor, oscillatory activity picked up by contacts in Vim (cerebellar thalamus) was invariably coherent with that in the sensorimotor cortex or contracting muscle in the 8-27 Hz range. Such coherence was absent in two of the four subjects with tremor associated with a cerebellar syndrome. Coherence between LFPs recorded from more caudally placed contacts and the sensorimotor cortex or contracting muscle was negligible in all patients. These caudally placed contacts demonstrated the highest sensory evoked potential in response to median nerve stimulation. Oscillatory activity in the cerebellar thalamus (Vim) lagged behind that in both cortex and muscle. Coherent activity between the cerebellar thalamus (Vim) and the cortex persisted at rest. It is suggested that rhythmicities in the 8-27 Hz range could provide the basis for a temporal framework that is widely distributed within the motor system.

Aged↗