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1.

Objective

Neurobiological models of depression posit limbic hyperactivity that should normalize after successful treatment. For psychotherapy, though, brain changes in patients with depression show substantial variability. Two critical issues in relevant studies concern the use of unspecific stimulation experiments and relatively short treatment protocols. Therefore changes in brain reactions to individualized stimuli were studied in patients with depression after eight months of psychodynamic psychotherapy.

Methods

18 unmedicated patients with recurrent major depressive disorder were confronted with individualized and clinically derived content in a functional MRI experiment before (T1) and after eight months (T2) of psychodynamic therapy. A control group of 17 healthy subjects was also tested twice without intervention. The experimental stimuli were sentences describing each participant''s dysfunctional interpersonal relationship patterns derived from clinical interviews based on Operationalized Psychodynamic Diagnostics (OPD).

Results

At T1 patients showed enhanced activation compared to controls in several limbic and subcortical regions, including amygdala and basal ganglia, when confronted with OPD sentences. At T2 the differences in brain activity between patients and controls were no longer apparent. Concurrently, patients had improved significantly in depression scores.

Conclusions

Using ecologically valid stimuli, this study supports the model of limbic hyperactivity in depression that normalizes after treatment. Without a control group of untreated patients measured twice, though, changes in patients'' brain activity could also be attributed to other factors than psychodynamic therapy.  相似文献   

2.
The investigation was intended to study the role ofbaroreceptors ofhemodynamically isolated zone of vertebral arteries in regulation of peripheral veins tonus, arterial pressure and external respiration. Pressure decrease in this vascular reflexogenic zone led to reflex responses of increase in femoral vein tonus, elevation of blood pressure level and stimulation of external respiration. The opposite reflex responses of cardio-respiratory functional system to initial pressure activation of vertebral arteries baroreceptors are observed. Basing on generalization of our own findings and similar physiological and morphological researches of other authors, it is established that afferentation from the vertebral artery zone is a reflexogenic factor of somatic muscles' veins tonus regulation. These reflexes of capacity vessels tonic activity changes are part of cardio-respiratory responses of maintaining the tissue gaseous exchange.  相似文献   

3.
The administration of threecyclic antidepressant melipramine to Wistar rats (15 mg/kg, intraperitonaly, 2 h before of experiments) increases time of an "open field" centre leaving. Thus melipramine does not influence horizontal and vertical activity, and also the number of bolus. At the development of a passive avoidance conditioned reflex melipramine significantly slows down realization of a unconditional mink reflex by untrained rats, increasing the latency of call in a dark compartment of the chamber. After training significant deterioration of a reflex reproduction is observed. At research of a defensive conditioned reflex of active avoidance melipramine worsens both development and reproduction of a reflex. The comparative analysis of the literary data of imipramine action on uptake of serotonine and noradrenaline and the analysis of the literary data on a role of these systems in the processes of learning and memory allows to suggest, that the effect of melipramine is connected mainly to amplification activity of serotoninergic system of a brain. It is supposed, that acute administration of melipramine creates emotionally negative state, worsens processes of learning and memory, strengthening mainly activity of a brain serotoninergic system. It specifies that serotoninergic system of a brain is system of punishment. Its activation interferes with formation and consolidation of connections between conditional and unconditional irritation.  相似文献   

4.
Psychotic disorders due to a known medical illness or substance use are collectively termed secondary psychoses. In this paper, we first review the historic evolution of the concept of secondary versus primary psychosis and how this distinction supplanted the earlier misleading classification of psychoses into organic and functional. We then outline the clinical features and approach to the diagnosis of secondary psychotic disorders. Features such as atypical presentation, temporal relation to detectable medical cause, evidence of direct physiological causal relationship to the etiological agent, and the absence of evidence of a primary psychotic illness that may better explain the presentation suggest consideration of a secondary psychosis. Finally, we discuss how careful studies of secondary psychotic disorders can help elucidate the pathophysiology of primary, or idiopathic, psychotic disorders such as schizophrenia. We illustrate this issue through a discussion of three secondary psychotic disorders — psychoses associated with temporal lobe epilepsy, velocardiofacial syndrome, and N‐methyl D‐aspartate (NMDA) receptor encephalitis — that can, respectively, provide neuroanatomical, genetic, and neurochemical models of schizophrenia pathogenesis.  相似文献   

5.
The review presents data on functional changes in fish, amphibians and birds associated with otolith organ activity after exposure to weightlessness during spaceflight. These data are of importance both for solving some fundamental problems of vestibulology and for practice. In the latter case, lower vertebrates are considered as a convenient and, most importantly, adequate model to unravel the mechanisms of vestibular disorders in humans. Analysis of the experimental results shows that weightlessness exerts no substantial effect on the formation and functional state of the otolith system in embryos of fish, amphibians and birds developing during spaceflight. Moreover, they even promote faster embryonic development of fish and amphibians as shown for mammalian fetuses. The experiments show that both in lower and higher vertebrates weightlessness brings about similar functional and behavioral changes. For example, in fish hatchlings and amphibian tadpoles (without lordosis) the vestibulo-ocular reflex was more pronounced immediately after orbital spaceflight than in control. An analogous alteration in the otolith reflex was observed in most cosmonauts after short-time space missions. In adult terrestrial vertebrates, as well as in humans, immediately after landing there was found a drop in the level of activity and deterioration of the equilibrium function and motor coordination. Another interesting finding was an unusual looping behavior when fish and tadpoles swam in loops post landing. Presumably, unusual motor activity of animals, as well as illusions arising in cosmonauts and astronauts during the transition from 1 to 0 g, have the same background being associated with changes in the stimulation pattern of the otolith organs. Considering the similarity of vestibular responses, the use of animal models seems very promising as allowing different invasive techniques.  相似文献   

6.
The analysis of proteomic samples with affinity labels has been firmly established as a tool for the post-genomic researcher. Recent examples highlight the advantages of profiling functionally active members of specific protein families to identify therapeutically relevant protein targets that have escaped normal physiological regulation leading to increased or decreased activity. This dysregulation may result from any number of biological changes that modulate a protein's activity; for example, post-translational modifications of the protein or an imbalance between the protein and its endogenous inhibitor(s). By providing a direct measure of a protein's functional activity, affinity probe analysis identifies these changes and allows investigators to focus their research efforts upon those proteins that are most likely to be responsible for the biological changes under evaluation.  相似文献   

7.
8.
The role of vasopressin (arginine–vasopressin) in animal adaptation to the effect of high environmental temperatures as well as a possibility to prevent development of thermal stress by use of vasopressin was studied under conditions of chronic experiments in hedgehogs. The experiments were carried out on a model of feeding behavior with objective recording of motor and autonomous components of the higher nervous activity and body temperature as well as the basal gas exchange. It is established that exposure of hedgehogs to a heat chamber at 40°C for 35 min is accompanied by a disturbance of autonomous functions and suppression of conditional reflex activity of the brain. The body temperature and oxygen consumption rise considerably on the background of the heat exposure. A preliminary injection of vasopressin at low dosages was found to prevent functional disorders and disturbances of the higher nervous activity in the hedgehogs exposed to high temperatures and to promote a better adaptation to heat exposure. The question of vasopressin as a specific antipyretic agent and of its possible clinical use is discussed.  相似文献   

9.
Electrophysiological and pharmacological analysis of L-Dopa-induced dyskinesia and tardive dyskinesia (L.DD) due to neuroleptics was performed on 12 patients with Parkinson's disease and on 12 others with psychotic diseases. This analysis included the examination of spinal reflexes, monosynaptic H reflex, polysynaptic cutaneous reflex of the lower limb, muscular responses to passive movement [stretch reflex and shortening reaction (SR)] and the study of the motor response to a dopaminergic stimulus (I.V. injection of Piribedil (PBD), a dopamine agonist). There was no difference in EMG activity between L.DD and TD. Three EMG patterns can be distinguished: anarchic discharge pattern (ADA), tonic grouping discharge pattern (AST) and rhythmic burst pattern (ABR). PBD effects indicate a possible relationship between the EMG patterns and the sensitivity level of the motor dopamine receptors. During L-Dopa dyskinesia and tardive dyskinesia, the same changes in spinal reflexes were observed. Muscle tone tested by muscular responses to passive movement (shortening and myotatic reaction) was normal. Monosynaptic excitability explored by H/M ratio was within the normal range. In contrast, the polysynaptic nociceptive reflex was increased in every case. In Parkinsonian patients with L-Dopa dyskinesia, this pattern of the spinal reflexes was significantly different in comparison to the rigid phase. Intravenous infusion of PBD suppressed tremor and provoked the occurrence of dyskinetic activity in Parkinsonian patients with L-Dopa dyskinesia during the rigid phase. During the dyskinetic phase, as in tardive dyskinesia, PBD increases these phenomena and changes EMG activity in rhythmic pattern. It is suggested that L-Dopa dyskinesia and tardive dyskinesia can be determined by testing EMG activity, spinal reflexes and dopaminergic reactivity. There is evidence to suggest that the various types of involuntary abnormal movement represent a single entity, and that dopamine receptor supersensitivity may be involved.  相似文献   

10.
On the basis of contemporary knowledge on close functional connections between respiratory and cardiovascular afferents a computerized experimental device was developed by means of which central information processing can be studied in dependence on respiration phase and the level of baroreceptor activity. In all the examined parameters (time of motor reaction of two hands, latency of eye-lid reflex) the greatest changes were observed at maximum baroreceptor activity. These changes were clearly distinguished by direction during the phases of inhalation and exhalation. Such effect is probably based on the fact that the influence of cardiovascular afferents on the level of central activity is modulated in respiration rhythm through the mechanism of breath "gating" of postsynaptic STN structures.  相似文献   

11.
The peculiarities of neurone bioelectric activity of sensory thalamic nuclei under electroacupuncture (EAP) stimulation have been studied in acute experiments on cats. EAP stimulation has been established to change spontaneous and evoked activity of neurones of sensory thalamic nuclei, that testifies to the development of a new functional state. The functional state of the cortex, in particular the second somatosensory region has been shown to determine the nature of neurone activation of sensory thalamic nuclei during the EAP stimulation. Schemes of possible organization of functional pools realizing the mechanisms of inhibition of nociceptive signals on central neurones during EAP way of reflex stimulation are suggested.  相似文献   

12.
Mechanisms of the amygdala central nucleus (CNA) influence on gastric motor reflex activity were studied in electrophysiological and neuroanatomical experiments in Wistar rats. In the anaesthetized animals, electrical stimulation of the CNA affected spontaneous gastric motility and caused inhibitory as well as excitatory changes of vagus-induced gastric relaxation. The most significant and mainly inhibitory effects were observed under the stimulation of the medial CNA. Microinjection of the anterograde tracer Phaseolus vulgaris-leucoagglutimn (PHA-L) into the different divisions of the CNA revealed direct projections from its dorso-medial portion to the gastric related area of the dorsal vagal complex. Electrical stimulation of this amygdaloid area was found to change activity of the bulbar gastric related neurons. Inhibitory and excitatory changes of their vagus-induced responses under the amigdala stimulation were manifested as a general modulation of all phases of the reaction or a selective modulation of some of them. These mechanisms may underlie the amygdalo-fugal modulation of gastric motor reflex activity.  相似文献   

13.
As the H reflex remains unable to assess mechanical changes intrinsic to a muscle, the aim of this study was to modify the H reflex techniques and to characterize the neural and mechanical components of muscle spasticity, relating the two components to clinical observations. Thirty-four patients featuring either a spinal-cord lesion (n=15) or stroke (n=19) and 23 neurologically normal subjects were recruited. Soleus H reflex and maximal M response (M(max)) were measured with electromyography and mechanomyography (MMG). The motoneuronal excitability was represented with the adjusted ratio of the H reflex to the M(max) (H/M(max)) and the ratio of the paired H reflexes (H(2)/H(1)). Muscle mechanical properties were characterized by the amplitude and median frequency of maximal M response recorded with MMG (MMG(Mmax)). The results showed that spastic patients exhibited a larger H/M(max), H(2)/H(1) and amplitude of MMG(Mmax) than the control group. H/M(max) and amplitude of MMG(Mmax) accounted for 55.7% of the variance in the Modified Ashworth Scale, the clinical hypertonia assessment. The amplitude of MMG(Mmax) correlated with functional impairments, as assessed with the Barthel index and Fugl-Meyer motor-assessment scale. It was concluded that spastic hypertonia involved an atypical increase in motoneuronal excitability and muscle mechanical properties, while impairment of functional performance and daily activity was attributable primarily to altered mechanical properties of a spastic muscle.  相似文献   

14.
The dynamics of kallikrein-kinin system components in the lymph of thoracic duct and blood following fever reaction of various duration has been studied in the experiment on rabbits. The experiments have shown that in prolonged fever reaction there are qualitative disorders in kinin system components ratio indicative of break in the system of regulatory links, its exhaustion and transformation of the physiological reactions into the pathogenic ones. One may assume that changes in kallikrein-kinin system activity in body fluid are the links in the complex of pathogenic disorders in the organ and system functional activity during prolonged fever reaction.  相似文献   

15.
There is considerable interest in the development of novel platinum-based anticancer drugs that overcome the disadvantages associated with the widely used drug cisplatin, which are its inactivity against some types of tumors and its toxic side effects. In this study we show the suitability of normal Raman spectroscopy (NRS) and surface enhanced Raman spectroscopy (SERS), assisted by density functional theoretical (DFT) calculations, for the characterization of Pt complexes. The Pt complexes studied include the established drugs cisplatin and carboplatin, as well as five novel Pt complexes with anticancer activity. DFT calculations at the B3LYP/LanL2DZ level are a good prediction of the experimental NRS spectra of small and medium sized Pt complexes. The use of SERS allows the investigation of Pt complexes at physiological concentrations, and the binding strengths of the different ligands can be determined. The formation of positively charged hydrolysis products may be necessary for SERS activity. The exiting group in the hydrolysis reaction can be identified.  相似文献   

16.
A computer model of body mass and composition in relation to gross energy balance is constructed. The model is built using conventional empirical physiological formulae rather than statistical or analytical mathematical techniques. The model is applied to the Minnesota and other experiments and produces as good or better simulations of observed values of changes in body weight than reported for other formulae or models. Alternative physiological mechanisms concerning metabolic adaptions to starvation, changes in time activity budgets and the energy equivalents of weight loss offer equally good simulations of experimental results. The present analysis highlights the survival value of a basal metabolic depression during starvation and indicates an optimal body composition of 10% mobilizable fat for starvation survival for a 70 kg man. Proper quantification of the effects of the physiological mechanisms involved depends on new experimental data, however. Long term continuous monitoring of time activity budgets are a necessary part of such experiments.  相似文献   

17.
Linking environmental conditions to the modulators of individual fitness is necessary to predict long‐term population dynamics, viability, and resilience. Functional physiological, behavioral, and reproductive markers can provide this mechanistic insight into how individuals perceive physiological, psychological, chemical, and physical environmental challenges through physiological and behavioral responses that are fitness proxies. We propose a Functional Marginality framework where relative changes in allostatic load, reproductive health, and behavior can be scaled up to evidence and establish causation of macroecological processes such as local extirpation, colonization, population dynamics, and range dynamics. To fully exploit functional traits, we need to move beyond single biomarker studies to develop an integrative approach that models the interactions between extrinsic challenges, physiological, and behavioral pathways and their modulators. In addition to providing mechanistic markers of range dynamics, this approach can also serve as a valuable conservation tool for evaluating individual‐ and population‐level health, predicting responses to future environmental change and measuring the impact of interventions. We highlight specific studies that have used complementary biomarkers to link extrinsic challenges to population performance. These frameworks of integrated biomarkers have untapped potential to identify causes of decline, predict future changes, and mitigate against future biodiversity loss.  相似文献   

18.
Clinicians and patients would benefit if accurate methods of predicting and monitoring bone strength in-vivo were available. A group of 51 human femurs (age range 21-93; 23 females, 28 males) were evaluated for bone density and geometry using quantitative computed tomography (QCT) and dual energy X-ray absorptiometry (DXA). Regional bone density and dimensions obtained from QCT and DXA were used to develop statistical models to predict femoral strength ex vivo. The QCT data also formed the basis of a three-dimensional finite element (FE) models to predict structural stiffness. The femurs were separated into two groups; a model training set (n = 25) was used to develop statistical models to predict ultimate load, and a test set (n = 26) was used to validate these models. The main goal of this study was to test the ability of DXA, QCT and FE techniques to predict fracture load non-invasively, in a simple load configuration which produces predominantly femoral neck fractures. The load configuration simulated the single stance phase portion of normal gait; in 87% of the specimens, clinical appearing sub-capital fractures were produced. The training/test study design provided a tool to validate that the predictive models were reliable when used on specimens with "unknown" strength characteristics. The FE method explained at least 20% more of the variance in strength than the DXA models. Planned refinements of the FE technique are expected to further improve these results. Three-dimensional FE models are a promising method for predicting fracture load, and may be useful in monitoring strength changes in vivo.  相似文献   

19.
In the first half of the sixties, general notions were formulated concerning the functional role of the orienting reaction (OR) in adaptive activity, its elicitation and habituation. These notions included the following: a) The OR is elicited only by significant changes in a situation. This implies that OR elicitation is preceded by brain processes (usually unconscious) pertaining to the evaluation of the significance of changes according to an existing hierarchy of motivations, attitudes, and goals. Therefore, the OR is of an active (vs. reactive) nature, i.e., is inevitably determined by internal factors of brain activity. b) The OR is not a unitary reaction, but a complex polyfunctional activity, different aspects of which are reflected in different OR components which can be modified rather independently. c) The OR represents the processes of organizing new (non-standard) actions: sensory, motor, or intellectual. OR habituation is a manifestation of attenuation of the active control of an action, and an increase in its automation. Thus, the emphasis in understanding the OR has shifted from a predominantly "sensualistic" platform to a predominantly "actualistic" one. In recent experiments, the role of emotional processes in the elicitation and habituation of components of the OR has been analyzed. Complex relations between the GSR and anxiety were found in a study of patients with acute alcohol withdrawal syndrome treated with different psychopharmacological agents. The study of auditory evoked potential habituation in depressive patients has shown the emotional state influence on sensory aspects of the OR with the participation of the OR brain mechanisms in perceptual defense.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

20.
Isoelectric focusing of iron saturated serum has been established as a convenient method for showing transferrin glycan microheterogeneity. In a clinical setting, the method is used in the detection of cerebrospinal fluid leakage, the screening for surreptitious alcohol abuse and in the diagnosis of the carbohydrate deficient glycoprotein syndrome. In normal physiological states it can also be used as a tool to probe for changes in N-glycosylation.  相似文献   

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