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PubMed1992

A [14C]2-deoxy-D-glucose study of brain structures related to conditioned emotional response in the rat.

We used [14C]2-deoxy-D-glucose (2-DG) to determine activated brain structures related to conditioned emotional response (CER) in rats. The experimental groups were conditioned with paired conditioned-stimulus (CS; flickering light and clicking sound) and unconditioned-stimulus (US; foot-shock) for either 25 or 50 trials. The control groups were also exposed to the same stimuli but in unpaired or random sequence. Two days after conditioning, rats were intravenously injected with [14C]2-DG and then exposed to the CS alone (CER test) in a shock box. Mean optical densities of 44 brain structures were measured with an autoradiogram, and their optical density ratios were compared by 2-by-2 (paired vs unpaired and 25 vs 50 trials) analysis of variance. Those brain structures were of 2 types; the first type showed similar changes of 2-DG uptake in both paired and unpaired groups (Areas 7 and 40 of the cerebral cortex, the habenula and the colliculus inferior), while the second type showed that 2-DG uptake increased in the paired groups but decreased in the unpaired groups (Areas 24, 10, 6, 4 and 3 of the cerebral cortex), as a function of number of trials. Because changes of 2-DG uptake in the first type structures and in Areas 3, 4 and 6 of the second type structures are regarded to reflect learning-nonspecific effects and task- or stimuli-related symmetrical activation, respectively, we concluded that Areas 24 (anterior cingulate cortex) and 10 (prefrontal cortex) were specifically related to conditioned emotional response.

Animals↗
PubMed1979

[Neuropathologic effects developing after administration of tetanus toxin to several rat brain structures].

Neuropathological syndromes following local tetanus toxin (TT) injection into different rat brain structures were studied. As demonstrated, there arose specific neuropathological signs dissimilar to those developing with different TT localization, i.e. as a rule the action of TT in the given brain parts was local. Experiments carried out confirmed the theory of the generator mechanisms of the neuropathological syndromes according to which specific manifestations of the corresponding syndrome were due to the localization of a generator of pathologically-enhanced excitation in definite brain structures.

Amygdala↗
PubMedDate not supplied

Need-informational interaction of brain structures.

The data presented deal with the role of four main brain structures in the development of emotional states and the organization of purposeful behavior. According to these data, the frontal neocortex orients behavior towards signals of highly probable events (reinforcement), whereas the hypothalamus is the basis for satisfaction of the dominant need. Unlike the neocortex, the hippocampus react to events of low probability, which is typical of emotionally stressed brain activity. Unlike the hypothalamus, the amygdala creates the balance, the dynamic coexistence, of competing needs (motivations) and emotions generated by such needs, which makes behavior more adequate. Individual characteristics of the interaction among the four brain structures is the basis for the individual types of higher nervous activity.

Amygdala↗
PubMed1996

The economy of winter: phenotypic plasticity in behavior and brain structure.

Mobile animals must learn the spatial distributions of resources. The cost of foraging increases dramatically for temperate-zone animals during the winter. Two strategies may be used to balance the energetic budget: reducing costs of foraging and reducing need to forage. Both strategies are correlated with changes in brain structure, specifically in the hippocampus, a fore-brain structure used by birds and mammals to map spatial distributions of resources. Small mammals that reduce their need to forage, through hibernation or reduction in body size, show a specific reduction in the structure and size of the hippocampus. The costs of foraging can be also decreased by migration to better foraging conditions or by food-storing, both of which decrease the temporal heterogeneity of food resources. Both of these latter strategies are associated with increased hippocampal structure; for food-storing birds, this increase is a seasonal phenomenon. Thus not only behavior, but also learning ability and even brain structures in adult animals, may be phenotypically plastic in response to the changing demands of the environment.

Adaptation, Physiological↗
PubMed1985

Catecholaminergic and serotoninergic brain structures in European green frogs: an autoradiographical study.

Aminergic brain structures have been investigated by means of light microscopical autoradiography after injection of the tritiated catecholamines noradrenaline and dopamine and the indoleamine (or tryptamine) serotonin into the brain cavity of frogs of the Rana esculenta complex. These amines are fairly specifically taken up by catecholaminergic and serotoninergic neurons, respectively, which are located in structures like the catecholaminergic preoptic recess organ; the mixed catecholaminergic-serotoninergic paraventricular organ/nucleus infundibularis-complex and nucleus reticularis mesencephali; the telencephalic septal and striatal areas and the tectum opticum, which contain many catecholaminergic axon terminals; the habenular area, which contains serotoninergic axon terminals. The autoradiographical data on the location and the nature of these aminergic brain structures agree well with the mainly fluorescence microscopical and immunocytochemical data from the literature. The autoradiographical detection method can be combined at the light and the electron microscopical level with other histological, histochemical, or immunohistochemical techniques in one and the same preparation, and the results of the different treatments may eventually be made visible simultaneously.

Animals↗
PubMed2000

A geometric morphometric assessment of change in midline brain structural shape following a first episode of schizophrenia.

BACKGROUND: Previous reports indicate that brain structural abnormalities may be progressive in some patients with schizophrenia. Our study was designed to determine deviations in the shape of midline brain structures at the time of onset of symptoms of schizophrenia and 3-5 years later. METHODS: Eleven landmarks were located on the midsagittal magnetic resonance imagery brain scans of 55 patients with schizophrenia and 22 nonpsychiatric control individuals. Geometric morphometric methods were used for the extraction of shape variables from landmark coordinates. Permutation tests were used to test the effects of gender, diagnosis, time elapsed since illness onset, and age on brain shape. RESULTS: The diagnosis-by-time interaction and the effect of gender were significantly different from zero (p<.027 and p <.039, respectively). The effect of time was significant in patients (p <.002), but not in control subjects. Some anatomical abnormalities in mean patient brain morphology seem to be present both at the time of diagnosis and at follow-up. These are similar to anomalies reported by previous geometric morphometrics studies. CONCLUSIONS: Some previously identified brain abnormalities are detectable at the time of first hospitalization. The rapid change in midline brain morphology in patients with schizophrenia during the subsequent 3-5 years is consistent with either a neurodegenerative disease process or an effect of treatment with psychiatric drugs. There is a sexual dimorphism in brain morphology that might be reduced by schizophrenia.

Adult↗
PubMed2002

[Disturbance of the knowledge representation in patients with arteriovenous malformations of the deep brain structures].

One hundred eighty patients with arteriovenous malformations (AVM) of the deep brain structures (caudate nucleus, thalamus, cingulated gyrus, hippocampus and corpus callosus) have been examined. Disturbance of the premorbid knowledge representations (selective retrograde amnesia) was found in 31 subjects. All the patients, in dependence in what structure the AVM was situated, survival severe intraventricular haemorrhage with long period of unconsciousness. The majority of the patients have haemorrhage from right hemisphere AVM. Neuropsychological syndrome was identical in all the patients: representation of major historical data was damaged worst, sequence of events representation was less damaged. Actualization of autobiography and events aspects was not practically disturbed. Neuropsychological examination revealed a combine dysfunction of frontal, temporal (preferentially right hemisphere) lobes and diencephalous region. The author concluded that in patients with AVM of the deep brain structures selective retrograde amnesia was found after severe intraventricular haemorrhage on the background of combined dysfunction of medio-basal regions (preferentially, right hemisphere) and diencephalon region. After surgical removal of any structure, any development of "novel" memory disturbances, like selective retrograde amnesia, was not observed.

Adolescent↗
PubMed1975

Adherence of rabbit erythrocytes to guinea-pig brain structures. Evidence for antigenic correlation between guinea-pig thymus and brain?

Similar to thymocytes in the thymic cortex, certain brain structures, such as nerve tracts and nerve cells of the Ammon's horn, show an affinity to rabbit erythrocytes (RRBC) which is exemplified by the adherence of RRBC to frozen brain sections. The experimental conditions of this adherence reaction are identical with that previously found with guinea-pig thymus and lymph node sections. From the results it may be concluded that receptor substances similar in nature on thymocytes and brain are responsible for this adherence phenomenon.

Aging↗
PubMed1978

Acetylcholine concentrations and turnover in rat brain structures during anesthesia with halothane, enflurane, and ketamine.

Acetylcholine and choline concentrations in brain structures of rats during anesthesia with halothane (0.7-1.0 per cent inspired), enflurane (2.7-3.0 per cent, inspired) and ketamine (40 mg/kg, iv) were measured by gas chromatography. The turnover rate (biosynthesis) of acetylcholine in vivo was estimated by infusing phosphoryl(Me-14C)choline intravenously, determining specific activities of choline and acetylcholine, and applying principles of steady-state kinetics to compute the fractional rate constant of acetylcholine. Acetylcholine concentrations in brain structures did not change during anesthesia. Halothane decreased the acetylcholine turnover rates in all parts of the brain. Enflurane decreased the acetylcholine turnover rate in the cerebral cortex only, but not in the caudate nucleus, the hippocampus, and the hypothalamic and thalamic regions. During anesthesia with ketamine, acetylcholine turnover rates were reduced in the caudate nucleus and the hippocampus, but not in the cerebral cortex and the hypothalamic and thalamic regions. The results suggest that acetylcholine turnover rate and utilization are related to anesthetic induced electrophysiologic changes in cortical and subcortical structures.

Acetylcholine↗
PubMed1990

Demonstration with [14C]2-deoxyglucose of brain structures involved in the masticatory activity of the hedgehog (Erinaceus europaeus).

The different brain structures activated during mastication in the hedgehog were revealed using Sokoloff's 2-deoxy-D-[1-14C]glucose technique. Brain sections of animals having received an injection of 2-deoxy-D-[1-14C]glucose during mastication were compared with those of animals treated during calm waking. Only brain structures that presented a 20% increase in glucose consumption were considered. The greatest increases were observed in the bulbar parvocellular reticulum and the trigeminal spinal nucleus (+80%), followed by structures also involved in mastication such as the trigeminal motor nucleus (+73%) and the hypoglossal nucleus (+64%). Other activated areas, not directly involved in mastication, were for example, the area postrema (55%), the olfactory (44%) and visual cortex (41%). This study emphasizes the importance of the bulbar parvocellular reticulum during mastication.

Animals↗
PubMed2004

Brain structure variation in great apes, with attention to the mountain gorilla (Gorilla beringei beringei).

This report presents data regarding the brain structure of mountain gorillas (Gorilla beringei beringei) in comparison with other great apes. Magnetic resonance (MR) images of three mountain gorilla brains were obtained with a 3T scanner, and the volume of major neuroanatomical structures (neocortical gray matter, hippocampus, thalamus, striatum, and cerebellum) was measured. These data were included with our existing database that includes 23 chimpanzees, three western lowland gorillas, and six orangutans. We defined a multidimensional space by calculating the principal components (PCs) from the correlation matrix of brain structure fractions in the well-represented sample of chimpanzees. We then plotted data from all of the taxa in this space to examine phyletic variation in neural organization. Most of the variance in mountain gorillas, as well as other great apes, was contained within the chimpanzee range along the first two PCs, which accounted for 61.73% of the total variance. Thus, the majority of interspecific variation in brain structure observed among these ape taxa was no greater than the within-species variation seen in chimpanzees. The loadings on PCs indicated that the brain structure of great apes differs among taxa mostly in the relative sizes of the striatum, cerebellum, and hippocampus. These findings suggest possible functional differences among taxa in terms of neural adaptations for ecological and locomotor capacities. Importantly, these results fill a critical gap in current knowledge regarding great ape neuroanatomical diversity.

Animals↗
PubMed2004

Mapping structural brain alterations in obsessive-compulsive disorder.

BACKGROUND: Recent technical developments have made it feasible to comprehensively assess brain anatomy in psychiatric populations. OBJECTIVE: To describe the structural brain alterations detected in the magnetic resonance images of a large series of patients with obsessive-compulsive disorder (OCD) using imaging procedures that allow the evaluation of volume changes throughout the brain. DESIGN: Case-control study. SETTING: Referral OCD unit in a tertiary hospital. PARTICIPANTS: A consecutive sample of 72 outpatients with OCD and 72 age- and sex-matched control subjects. INTERVENTIONS: Three-dimensional sequences were obtained in all participants. A statistical parametric mapping approach was used to delineate possible anatomical alterations in the entire brain. To preserve volumetric information, voxel values were modulated by the Jacobian determinants (volume change measurement) derived from spatial normalization. MAIN OUTCOME MEASURES: Voxelwise brain volumes. RESULTS: The brains of patients with OCD showed reduced gray matter volume in the medial frontal gyrus, the medial orbitofrontal cortex, and the left insulo-opercular region. A relative increase in gray matter volume was observed bilaterally in the ventral part of the putamen and in the anterior cerebellum. All these brain alterations were abnormally correlated in patients with OCD, and age statistically significantly contributed to the relative enlargement observed in the striatal areas. Disease severity, the nature of symptoms, and comorbidities were not related to the changes described. Nevertheless, patients with prominent aggressive obsessions and checking compulsions showed reduced amygdala volume in the right hemisphere. CONCLUSIONS: The pattern of anatomical features depicted by this voxelwise approach is consistent with data from functional studies. The reported anatomical maps identified the specific parts of the frontostriatal system that were altered in patients with OCD and detected changes in anatomically connected distant regions. These data further define the structural brain alterations in OCD and may contribute to constraining the prevailing biological models of this psychiatric process.

Adolescent↗
PubMedDate not supplied

[Fluorothane pharmaco kinetics in brain structures and the permeability of the hemato-encephalic barrier in postnatal ontogeny].

Distribution of ftorotan in the brain structures (hemispheres, thalamus, cerebellum, limbic structures) and blood, and permeability of the blood brain barrier of the listed brain structures were studied by gas chromatography in postnatal ontogenesis (7, 17, 30, 60 and 90 days) of white rats during three stages of anesthesia -- initial, "surgical" and final ones. It has been established that the histohematic barrier is most permeable prior to 17-day age; the blood brain barrier is the least permeable in 7- and 17-day-old animals. Sorption of the brain tissue increases after 17 days and reaches maximum by day 90 of the postnatal development.

Animals↗
PubMed2004

The role of sub-cortical brain structures in emotion recognition.

PRIMARY OBJECTIVE: This study investigated the role of sub-cortical brain structures in emotion recognition. METHODS AND PROCEDURES: Fourteen patients (eight left, six right) with sub-cortical brain damage (SS) and 14 matched healthy volunteers (HV) were recruited. A brief neuropsychological battery was administered to measure working memory, visual inattention, Stroop effect and visual organization. A facial and prosodic emotion recognition battery previously developed was used. RESULTS: SS patients were generally impaired on emotion recognition, with the exception of facial emotion discrimination and tasks involving happy expressions, relative to HV. Preliminary analyses also showed no statistical difference between patients with left- and right-sub-cortical brain damage in terms of emotion recognition. CONCLUSIONS: The findings provide further support for the role of sub-cortical brain structures (and the damage thereof) as well as probable frontal-limbic neural networks in recognizing basic emotions.

Aged↗
PubMedDate not supplied

[Corticosterone receptor binding by various brain structures in extreme body states].

Studies on receptor binding of 3H-corticosterone in different brain structures of mature Wistar rats after a single x-irradiation at a dose of 12.9 mCoul/kg, short-term vertical vibration, glucocorticoid application, and surgical adrenalectomy showed a high sensitivity of all studied structures to the body level of glucocorticoids. Any of these influences caused redistribution of receptor binding of 3H-corticosterone in all brain structures, with a marked effect in the parietal cortex and mediobasal hypothalamus, which characterized the central mechanisms of regulation of the pituitary-adrenal system under extreme influences.

Adrenalectomy↗
PubMed1996

Effects of diazepam on fentanyl-induced epileptoid EEG activity and increase of multineuronal firing in limbic and mesencephalic brain structures.

Electroencephalographic and clinical signs of epileptoid activity have been associated with the administration of fentanyl during surgery in patients. These phenomena have been in turn related to changes in metabolic rate, oxygen consumption, and blood flow in specific brain structures both in humans and experimental animals. However, direct evidence showing changes in neuronal firing in specific brain regions during fentanyl-induced epileptoid activity has not been reported. Eight adult male cats with chronically implanted bipolar electrodes in the mesencephalic reticular formation, hippocampus, amygdala, and parieto-occipital cortex were included in the study. Different treatments, i.e., vehicle-fentanyl or diazepam-fentanyl, were administered to the experimental animals at 7-day intervals under neuromuscular blockade and assisted ventilation. Electroencephalographic (EEG) seizures, grouped and isolated spikes, and significant increases of multineuronal activity (MUA) were elicited by fentanyl, 50 micrograms/kg iv, in these brain structures. Both EEG and MUA changes reached their maximal values within 6 min of fentanyl administration, and then diminished as time elapsed. Diazepam, 100, 200, or 400 micrograms/kg, but not 50 micrograms/kg iv, significantly reduced or prevented the fentanyl-induced epileptoid EEG activity and MUA increases. The present results show that both fentanyl-induced epileptoid EEG activity as well as the concomitant increase in MUA of brain subcortical structures are part of the same epileptogenic phenomenon, mainly generated at limbic structures. In addition, the effects of diazepam against both epileptoid EEG activity and increase of MUA of brain subcortical structures support the use of benzodiazepines as premedicants for fentanyl anesthesia in order to prevent or to reduce epileptoid phenomena that can result from opioid administration during the anesthetic procedures.

Animals↗
PubMed2002

Genetic contributions to regional variability in human brain structure: methods and preliminary results.

Twin studies provide one approach for investigating and partitioning genetic and environmental contributions to phenotypic variability in human brain structure. Previous twin studies have found that cerebral volume, hemispheric volume, ventricular volume, and cortical gyral pattern variability were heritable. We investigated the contributions of genetic and environmental factors to both global (brain volume and lateral ventricular volume) and regional (parcellated gray matter) variability in brain structure. We examined MR images from 10 pairs of healthy monozygotic and 10 pairs of same-sex dizygotic twins. Regional gray matter volume was estimated by automated image segmentation, transformation to standard space, and parcellation using a digital atlas. Heritability was estimated by path analysis. Estimated heritability for brain volume variability was high (0.66; 95% confidence interval 0.17, 1.0) but the major effects on lateral ventricular volume variability were common and unique environmental factors. We constructed a map of regional brain heritability and found large genetic effects shared in common between several bilateral brain regions, particularly paralimbic structures and temporal-parietal neocortex. We tested three specific hypotheses with regard to the genetic control of brain variability: (i) that the strength of the genetic effect is related to gyral ontogenesis, (ii) that there is greater genetic control of left than of right hemisphere variability, and (iii) that random or fluctuating asymmetry in bilateral structures is not heritable. We found no evidence in support of the first two hypotheses, but our results were consistent with the third hypothesis. Finally, we used principal component (PC) analysis of the genetic correlation matrix, to identify systems of anatomically distributed gray matter regions which shared major genetic effects in common. Frontal and parietal neocortical areas loaded positively on the first PC; some paralimbic and limbic areas loaded negatively. Bilateral insula, some frontal regions, and temporal neocortical regions functionally specialized for audition and language loaded strongly on the second PC. We conclude that large samples are required for powerful investigation of genetic effects in imaging data from twins. However, these preliminary re. sults suggest that genetic effects on structure of the human brain are regionally variable and predominantly symmetric in paralimbic structures and lateral temporal cortex.

Algorithms↗
PubMed2001

Genetic deletion of angiotensin AT2 receptor leads to increased cell numbers in different brain structures of mice.

Angiotensin II (Ang II) is a potent vasoactive peptide and displays growth factor-like properties. Different high-affinity Ang II receptor subtypes (AT1A, AT1B and AT2) have been cloned. They are expressed in various brain structures. Additionally, it has been assumed that Mas could interact directly or indirectly with the renin-angiotensin system. The AT1 receptor mediates pressor and mitogenic effects of Ang II, whereas physiological function and signaling mechanisms of the AT2 receptor remain poorly understood. Recent reports have shown that Ang II could mediate apoptosis through AT2 receptors. Since the AT1A, AT2 and Mas knockout mice provide new tools for uncovering potential actions of Ang II, the cell number in different brain structures of male adult wild-type mice and mice deficient for AT1A, AT2 or Mas was evaluated to get more insight into the role of Ang II in central nervous system development. In nearly all investigated brain structures (cortex, hippocampus, amygdala, thalamus), the cell number was significantly higher in AT2-deficient mice in comparison to wild-type mice. To the contrary, in AT1A-deficient mice the cell number was significantly less than in controls in the lateral geniculate and the medial amygdaloid nucleus. However, cell numbers were not changed in Mas-knockout mice compared to their wild-types. These results show the contrary effects of both angiotensin receptors on cell growth and represent the first demonstration of their action on neuronal cell development evidenced in the adult mouse brain.

Angiotensin II↗