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1.
In 21 subacute or chronic cats the influence of gallbladder distention on heart rate, respiratory movements, bio-electrical activity of the cerebral cortex and motor behavior were studied under normal conditions and after intraperitoneal administration of a ganglionic blocking agent. In control groups without administration of the drug, changes of heart and respiratory rates were observed during the mechanical stimulation of the gallbladder. These effects were independent of a sleeping or non-sleeping state of the animal. In some cases viscerovisceral reactions could be accompanied by an arousal reaction. After administration of the blocking agent in amounts ranging between 5–50 mg/kg body wt the viscerovisceral reactions were inhibited, whereas the behavioral arousal remained.  相似文献   

2.
In 12 chronic cats the effects of mechanical stimulation (distention) of the gallbladder on heart rate, respiratory movements and bioelectrical activity of the cerebral cortex were studied under normal conditions and after intraperitoneal administration of atropine. In the control group without atropine a decrease or an increase of heart rate and of respiratory movements occurred, depending on stimulation intensity. These changes were independent of an activated or inactivated EKG. Behavioral arousal was not seen in every cat. After administration of atropine in doses from 0.2 to 2.0 mg per kg body weight, the changes in heart rate, respiration and EKG were suppressed or completely disappeared.  相似文献   

3.
This study is to compare heart reactivity between normals and anxiety neurotic patients. Five male and five female patients with anxiety neurosis and four male and five female normal persons were submitted to classic delayed conditional reflexes with different probabilities of reinforcement (shock), to a defensive instrumental conditional reflex, and to a neutral nonreinforced stimulus. The basal heart frequency was higher in neurotics and in women than in normals and men. The conditional stimulus (CS) associated with a shock generally produced a bradycardia in normal individuals and in neurotic men, but a tachycardia in neurotic women (effects most pronounced in cases with 100% shock probability). The instrumental CS caused a tachycardia in all of the groups, with highest values in neurotic women. The neutral stimulus produced bradycardia in all persons. The aftereffect of the light stimulus depended on whether a shock was administered and on the CS. The differences between neurotics and normals are explained as caused by the heightened excitatory level of the CNS of the neurotic group, produced by the unspecific activating effect of chronic anxiety, and differences of plastic processes in both groups, resulting in different effects of phasic anxiety on the heart. Complex inhibitory-excitatory interactions of the sympathetic and the vagal system underlying the heart rate changes may be assumed. Possible mechanisms leading to sex differences are discussed.  相似文献   

4.
Blink reflexes to acoustic probes, heart rate, and subjective reports were studied during affective memory imagery. Thirty-six undergraduates memorized 6 pairs of neutral and fearful sentences. After learning each pair, they relaxed and listened to a series of uniform tones, one every 6 s. A change in tone pitch (higher or lower) cued recall of one of the two sentences. At the first cue tone, groups (n = 12) were under different instructions: (a) ignore the sentence and relax, (b) silently articulate the sentence, and (c) imagine the sentence content as a personal experience. At the second cue tone, all subjects performed the imagery task. Startle probes (50-ms, 95-dB white noise) were presented unpredictably during relaxation and recall trials. Probe blink reflexes were larger and cardiac rate faster at fear sentence recall than at neutral sentence recall or relaxation. For probe reflexes, this effect was greater for imagery than for nonsemantic recall tasks.  相似文献   

5.
A Pavlovian methodological counterpart to the use of druginduced changes in operant rates of responding was used to assess the temporal characteristics of d-tubocurarine chloride effects on the heart rate conditional reflex in rats. After a stable conditional reflex had been established, the base heart rate, as well as the unconditional and conditional reflex, was monitored during administration of the drug. A sizable behavioral effect was reflected in all three measures, including a temporary abolition of the conditional and unconditional reflexes. An interpretation of these results was discussed, and further development and application of this specific methodology was explored.  相似文献   

6.
Interaction between penile reflexes and copulation in male rats   总被引:1,自引:0,他引:1  
Intact, unanesthetized male rats were place in a supine position, with the penile sheath continuously retracted. Three forms of penile reflex were displayed: erections, cups, and flips. The reciprocal relation between copulation and the penile reflexes occurring in supine tests was explored in four experiments. In Experiment 1, sexual exhaustion depressed all penile reflexes, but the reflexes returned to baseline levels within 8 hr, long before copulatory potential. In Experiment 2, reflexes were depressed to exhaustion levels after fewer ejaculations than were required for sexual exhaustion, an indication that reflexes are more readily evoked during copulation than in supine tests. Experiment 3 determined that a rat's penile-reflex potential may be enhanced by placing the rat in a copulation-test cage, by allowing the male a few antecedent intromissions, or by allowing an antecedent ejaculation. The display of penile reflexes within 1 min after ejaculation suggests that the period of reduced sexual arousability following ejaculation is not due to reduced excitability in the spinal mechanisms controlling penile reflexes. In Experiment 4, 1 hr of penile-reflex elicitation had no effect on subsequent copulatory behavior. Thus, sexual stimulation may increase or decrease penile-reflex potential, but a reciprocal influence was not detectable.  相似文献   

7.

Results

During flexion of the hind leg to US or CS, as well as during spontaneous lifting of the leg, the blood flow in the appropriate femoral artery suddenly increases for 10–14 seconds, systemic blood pressure shows transient decrease, while heart rate and respiratory movements are accelerated. To perform one flexion and subsequent extension about 7 ml extra blood flow is necessary during UR and 5 ml during CR. During acute extinction of the CR the described vegetative changes become less and less, parallel with the gradual decrease of flexor movement of the hind leg. The sequence of extinction of the individual measured parameters was as follows: flexion, blood pressure, blood flow, heart rate, and lastly, respiration. In the mechanism of the vegetative changes accompanying the conditional hind leg flexion three main components are involved: (1) muscular-visceral reflexes originating from different receptors of the contracting muscles, (2) the emotional changes, and (3) the conditional component as a separate conditional reflex for each measured parameter. Principles underlying the formation of conditional reflexes are discussed under the headings ofschizokinesis, peripheral andcentral stimulations.Organ responsibility is the basis for the formation of the conditional reflex.  相似文献   

8.
As psychostimulants are widely abused, their neurochemical and behavioral effects have been extensively studied for many years. Our previous data demonstrate that paradoxical sleep deprivation (PSD) enhances drug-induced penile erection and ejaculation. PSD in association to drugs of abuse like cocaine potentiated genital reflexes in male rats. In this sense, the present study investigated if three substances abused by young people--such as Delta(9)-tetrahydrocannabinol (Delta(9)THC), alcohol and caffeine--had any significant effect on the genital reflexes in PSD rats. The results indicated that PSD induced erection in 50% of the rats and 20% ejaculated. In addition, there was no significant alteration in the number of animals exhibiting genital reflexes neither on the frequency of these behaviors when challenged with Delta(9)-THC or alcohol or caffeine after 96 h of PSD. These findings show that Delta(9)THC, alcohol and caffeine when administrated isolated did not produce alterations in genital reflexes in the PSD male rats.  相似文献   

9.
The aim of the study was to explore the effect of visualizing food images under different mood states and food restriction conditions on the emotional modulation of two defense reflexes (startle reflex and cardiac defense). 72 women at risk of suffering from bulimia nervosa were assigned to two groups: 1) a group under induced positive, neutral, or negative mood state and, 2) a 6-hour-food-deprived group or a non-deprived group. Second-by-second heart rate and electromyogram activity from the orbiculari oculi region were recorded after the auditory stimulus. The results showed that, while viewing food images, non-deprived women under negative mood state potentiated the cardiac defense response and the startle motor reflex. Results are discussed in the context of emotional eating theories and Peter Lang's motivational priming model.  相似文献   

10.
The use of neurological tests in various states of undernutrition has confirmed the presence of delays in reflex ontogeny. Glucocorticoid administration in conditions of normal nutrition produces diminished growth and alterations in brain development similar to those observed in malnutrition, but there is not enough evidence about its effect on reflex development. In addition, some facts lead us to think that the use of permissive doses of these hormones during gestation could alleviate some of the effects of protein malnutrition on the development of pups. In the present study the ages at which certain reflexes appeared in the offspring of Wistar rats (Rattus norvegicus) fed a 20% (N) or 10% (M) protein diet from a week before conception to the end of lactation were observed. Each dietary group was subdivided into two: mothers receiving a daily injection during gestation either of a 0.9% NaCl (S) solution or of a 0.5 mg/100 g weight hydrocortisone acetate (C) solution. Results showed that the NS group of pups generally presented earlier ages of appearance of the variables under study than the remaining groups. Pups of the NC group presented delays in the age of appearance of reflexes. Finally, protein malnutrition delayed the appearance of reflexes and this effect seemed to be attenuated by treatment with hydrocortisone. Thus, hydrocortisone administration in protein malnutrition conditions seems to be beneficial although the results are harmful when administered under normal nutritional conditions.  相似文献   

11.
The results of studies performed by the authors show that time measurements of proprioceptive muscular reflexes (triceps surae and tibialis posterior reflexes) may be considered a valuable addition to methods of topical diagnosis of radicular disturbances in the lumbosacral region. The reflexes were tested in twenty normal subjects. There were found an intraindividual constancy of the respective reflex time with a maximum deviation of 2 ms as well as a lateral variability up to 1.3 ms. Radicular compressions resulted in an increase in reflex time by 2 to 66 ms or failure of the reflex potential to be recorded. The pathological cases were compared with clinical and neurological studies, positive myelographies using radiopaque substances, and results of surgical operations. Compared with the results of surgical operations, changes in reflex time indicated damage to the reflex arc in ninety percent of the cases.  相似文献   

12.
John Locke (1632-1704) and Villaume (1746-1825) were already familiar with the method with which we, in our "individual therapy", treat neurotic patients. The question whether conditional reflexes and the elimination of their effects play an essential part in the procedure must be denied.  相似文献   

13.
Core affect and the psychological construction of emotion   总被引:19,自引:0,他引:19  
At the heart of emotion, mood, and any other emotionally charged event are states experienced as simply feeling good or bad, energized or enervated. These states--called core affect--influence reflexes, perception, cognition, and behavior and are influenced by many causes internal and external, but people have no direct access to these causal connections. Core affect can therefore be experienced as free-floating (mood) or can be attributed to some cause (and thereby begin an emotional episode). These basic processes spawn a broad framework that includes perception of the core-affect-altering properties of stimuli, motives, empathy, emotional meta-experience, and affect versus emotion regulation; it accounts for prototypical emotional episodes, such as fear and anger, as core affect attributed to something plus various nonemotional processes.  相似文献   

14.
Higher reflexes     
The term reflex is used in a broad sense. Reflexes having a drive component are denoted as higher. Four types of higher reflexes are distinguished: avoidance, escape approach and consummately. Each of these reflexes has a different drive component. The result of the reflex is a removal of the corresponding drive. For this purpose three different strategies are used. Complex higher reflexes are usually programmed and occur frequently in a chain form. A given function of an organism is performed by a system of reflexes controlled by one or more drives.  相似文献   

15.
Emotional reactions were assessed to pictorial stimuli presented in a continuous stream at rapid speeds that compromise conceptual memory and the processing of specific picture content. Blocks of unpleasant, neutral, or pleasant pictures were presented at the rate of either three pictures per second or seven pictures per second. Even with rapid presentation rates, startle reflexes, corrugator muscle activity, and skin conductance responses were heightened when viewing unpleasant pictures. These effects were stronger later in the aversive block, suggesting that cumulative exposure increasingly activates the defense system. The findings suggest that, despite conceptual masking inherent in rapid serial visual presentation, affective pictures prompt measurable emotional engagement.  相似文献   

16.
The acoustic startle and trigeminal blink reflexes share the same motor output. Since caffeine has been shown to augment the startle reflex, it was proposed that caffeine would also increase the trigeminal blink reflex. In 6 humans, the effects of caffeine (100 mg) on the trigeminal blink reflex were investigated. Reflex blinks were elicited by stimulation of the supraorbital branch of the trigeminal nerve. Following ingestion of caffeinated coffee, reflex blinks increased in amplitude and duration and occurred at a shorter latency than reflex blinks following ingestion of decaffeinated coffee. Since the blink reflex is a brainstem reflex, these results suggest that the psychomotor effects of caffeine facilitate brainstem processing.  相似文献   

17.
This study examined the effect of level of attention engagement on the modification of the blink reflex in young infants. Infants at 8, 14, 20, or 26 weeks of age were presented with interesting visual or auditory stimuli. At delays defined by changes in heart rate known to be associated with sustained attention or attention disengagement, blink reflexes were elicited by visual or auditory blink reflex stimuli. Blink amplitude varied according to the level of attention, and the match between the foreground and blink reflex stimulus. If the infant was attending to the foreground stimulus, a blink reflex stimulus in the same modality resulted in enhanced blink reflex magnitude. A blink reflex stimulus in the other modality resulted in an attenuated blink reflex magnitude. If attention was not engaged with the foreground stimulus, this modulation of the blink reflex did not occur. This ‘selective modality effect’ showed an increasing tendency to occur between 8 and 26 weeks of age. These results show that selective attention to modalities increases over this age range.  相似文献   

18.
Our interest in cardiovascular conditioning, particularly the fact that conditional tachycardia has been observed in many dogs after only one or two combinations of conditional and unconditional stimuli, led us to investigate conditioning using a single application of an unconditional stimulus. Initially we studied the effect of orienting stimuli (soft tones) on the heart rate in 9 dogs. After 30–100 presentations of the tones alone, each dog received on one occasion a 25-volt shock (sufficient to cause yelping and struggling) to a leg as unconditional stimulus immediately following a tone. Thereafter 30–100 additional tones were presented with no further shock. Little or no heart rate change occurred during the orienting tones (before shock). Three types of cardiac changes occurred during experimental sessions after the shock: 1) Increased heart rate during the tones in 5 dogs; 2) Generalized lowering of heart rate during all experimental sessions after shock in 4 dogs; 3) Electrocardiographic changes during tones in 3 of the dogs also showing the generalized decrease in heart rate. No motor flexion conditional reflexes developed. Tones an octave different in pitch from the one associated with the shock also caused approximately the same heart rate changes, indicating lack of differentiation. This one-trial cardiac conditioning persisted after the single conditioning trial for more than a month in 2 dogs and for at least 3 to 5 sessions in the other dogs.  相似文献   

19.
Locomotor avoidance conditioning and locomotor food conditioning in male albino rats demonstrated that locking of temporary connections is accomplished by coupling of phases of different synchronized periodic neural processes. Phase coupling was verified by the formation of parallel periodic courses of reaction times and motor reaction times in the process of elaboration of conditional avoidance reflexes, and by the curve of the corresponding correlation coefficients, which were calculated from the reaction times and motor reaction times in food conditioning measured every day during the period of stabilization. The authors hold the view that a locking mechanism based on the synchronization of periodic processes in conditioning is most compatible with efficient formation of conditional reflexes and can promote adaptation. Furthermore, it is assumed that information storage, too, occurs periodically, according to the principle of rotary storage.  相似文献   

20.
Stress exerts deleterious effects on the cardiovascular system. Left ventricular hypertrophy has been identified as a risk factor for heart disease. The effects of stress on other heart parameters, including heart size and heart shape, are not well-characterized. In addition, the extent to which males and females differ in stress effects on these measures has not been examined, but may help to further explain gender differences in heart disease morbidity and mortality. The present experiment examined effects of mild daily stress on heart morphology and blood volume (obtained by ex-sanguination at decapitation) in 39 male and 40 female rats of two strains. Following 14 days of stress exposure, rats were killed and blood volume was measured. Heart length, heart weight, left ventricle cavity width, right ventricle width, lateral wall thickness, anterior wall thickness, posterior wall thickness, and septal wall thickness were measured. In males, after controlling for body weight, stress decreased heart length and left ventricle cavity width and increased septal wall thickness. In females, after controlling for body weight, stress reduced total blood volume, but did not significantly affect other heart parameters. These findings suggest that stress exposure can alter heart morphology and blood volume and that there are sex differences in these effects.  相似文献   

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