SEARCH · PubMed Health

Results for “Conditioning, Operant”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 991 records · Page 55Linked to original sources

PubMed2001

[Dynamics of instrumental reflex changes following transection of the corticospinal tract and ablation of the cerebral cortex sensorimotor region in rats].

Unilateral transection of bulbar pyramid performed prior to ablation of the ipsilateral sensomotor cortex was shown to facilitate recovery of operant conditioning and compensatory processes in rats. There was no such corticofugal plasticity in ablation of the sensomotor cortex alone. The phenomenon may be explained by switching of descending influences on the cortico-rubrospinal system through participation of the loop: corticorubral projection--red nucleus--inferior olive--cerebellum--thalamus--cerebral cortex.

Animals↗

PubMed2001

On killing. II: The psychological cost of learning to kill.

Military and law enforcement studies reveal that interpersonal combat is a universal human phobia. Physiological responses include forebrain shutdown and sympathetic arousal. A resistance to killing exists in the midbrain of most healthy members of most species, becoming ascendant when the forebrain shuts down, and can prevent soldiers from performing in combat. The U.S. military has increased participation in killing activities from 20% in World War II to 95% in Vietnam by operantly conditioning responses. Conditioning is achieved through training that closely resembles battle situations and inadvertently occurs when children see violence as entertainment. The price of this conditioning is an increase in post-traumatic stress disorder which can be defrayed through debriefing, social acceptance, and prevention of atrocities. Similar techniques may be used to prevent PTSD in civilian populations involved in tragedies like school shootings.

Arousal↗

PubMed1975

Pharmacological properties of 6,7-tetramethylene-5-phenyl-1,2-dihydro-3H-thieno[2,3-e](1,4)-diazepin-2-one (QM-6008, thiadipone), a new psychotropic drug.

The pharmacological actions of 6,7-tetramethylene-5-phenyl-1,2,-dihydro-3H-thieno]2,3-e](1,4)-diazepin-2-one (QM-6008, thiadiapone), a new psychotropic drug, have been studied. QM-6008 shares many of the psychosedative effects in rodents of benzodiazepines. The electroencephalographic actions in rats and rabbits of QM-6008 and chlordiazepoxide are also rather similar. This new compounds is endowed with clear conflict attenuating properties in an approach-avoidance schedule and can be considered, in consequence, as a new potentially useful anxiolytic drug. In other operant conditioning procedures in rats--Variable Interval and Discriminated Avoidance--QM-6008 induces an increase in response rate which is not generally shared by chlordiazepoxide. The psychopharmacological data collected in the present work leal to classify this new thienodiazepine derviative within the fram of tranquilizers of the benxodaizapine type. The sedative effects of QM-6008 appear howerer to be less potent and the psychostimulatn effects more markde than those ofchlordiazeposide.

Aggression↗

PubMed2002

Rats fail to discriminate quinine from denatonium: implications for the neural coding of bitter-tasting compounds.

Recent molecular findings indicate that many different G-protein-coupled taste receptors that bind with "bitter-tasting" ligands are coexpressed in single taste receptor cells in taste buds, leading to the prediction that mammals can respond behaviorally to structurally diverse "bitter" tastants but cannot discriminate among them. However, recent in situ calcium-imaging findings imply that rat taste receptor cells are more narrowly tuned to respond to bitter-tasting compounds than had been predicted from molecular findings, suggesting that these animals can discriminate among these chemicals. Using an operant conditioning paradigm, we demonstrated that rats cannot discriminate between two structurally dissimilar bitter compounds, quinine hydrochloride and denatonium benzoate, despite the fact that these tastants are thought to stimulate different taste receptor cells. These rats were nonetheless able to show concentration-dependent avoidance responses to both compounds in brief-access tests and to discriminate among other taste stimuli, including quinine versus KCl, denatonium versus KCl, and NaCl versus KCl. Importantly, the concentrations were varied in the discrimination tests to render intensity an irrelevant cue. We conclude that denatonium and quinine produce a unitary taste sensation, leaving open the likely possibility that other compounds fall into this class. Although a broader array of compounds needs to be tested, our findings lend support to the hypothesis that there is only one qualitative type of bitterness. These results also highlight the need to confirm predictions about the downstream properties of the gustatory system, or any sensory system, based on upstream molecular and biophysical events.

Animals↗

PubMed1975

[Instrumental reconditioning at an ambient temperature of 35 +/- 1 degrees C after suppression of the reward in growing rat].

By shortening to 5 seconds the burst of "fresh air" delivered by one level-pressing in 6 or 3 20 minutes sessions of operant conditioning at the ambient temperature of 35 +/- 1 degrees C brings 7 and 3 growing rats up to the maximal value of instrumental acquisition in 2 and 1 sessions. The experiment is going on with 40 minutes sessions in which the first 15 minutes belongs to the reward suppression. In spite of this inhibitory factor there is through the stimulus presence reconditioning which leads to instrumental adaptation at the ambient hyperthermia of 38.5 +/- 0.5 degrees C. At this temperature the instrumental activity level is the same as at 35 +/- 1 degrees C, in 20 minutes and the rectal temperature is rising up to provide compensatory work (+ 2.39 degrees C. instead of + 1.34 degrees C. at 35 +/- degrees C.).

Age Factors↗

PubMed1977

Auditory reinforcement in profoundly retarded multiply handicapped children.

Profoundly retarded multiply handicapped children were placed in a situation where auditory stimulation was made contingent on a visually directed level-pulling response. Two experiments were performed. In the first, a technique for establishing an effective reinforcer from a range of possible reinforcing stimuli was evaluated. In the second experiment, a multiple schedule was used to compare the effectiveness of a reinforcer whose efficacy was established in Experiment 1 with a second auditory stimulus. The selection of auditory reinforcers and an evaluation of their relative potency was achieved using these techniques. The results show the feasibility of systematic measurement of operant-conditioning effects with very severely handicapped subjects in a laboratory situation. The information gained concerning the effectiveness of auditory reinforcers has implications for behavior-modification programs with these children.

Acoustic Stimulation↗

PubMed1978

[Proprioceptive feedback and temporal regulation in cats].

Temporal regulation in cats was studied using operant conditioning techniques; milk was delivered according to either a two-lever response duration schedule or a two-lever DRL schedule. After an equal number of experimental sessions, the subjects on the DRL schedule reached larger delay values than the subjects on the response duration schedule. Hypotheses concerning the intervention of proprioceptive feedback in the temporal regulation of motor behavior are discussed.

Animals↗

PubMed2004

[Determination of mercury in battery by microwave digestion cold atomic absorption spectrometry].

In this paper, a method of microwave digestion followed by cold atomic absorption spectrometry (CAAS) for the determination of mercury in battery was developed. Microwave digestion conditions and operational conditions of CAAS were optimized. The digestive solution was a mixture of hydrochloric acid-sulfuric acid (4:1, volume ratio) and the digestive time was 3 min at a microwave power of 1.0 MPa. The reaction medium was 0.5 mol x L(-1) sulfuric acid at room temperature. The characteristic concentration was 0.25 microg x L(-1). Five battery samples were determined, the recoveries were from 99.9% to 113%, and the relative standard deviations were from 4.85% to 11.9% (n = 6). The analytical results were satisfactory. The method is fast, simple, accurate and solvent-saving.

English Abstract↗

PubMed2006

A remote controlled multimode micro-stimulator for freely moving animals.

This paper presents a remote controlled multimode micro-stimulator based on the chip nRF24E1, which consists mainly of a micro-control unit (MCU) and a radio frequency (RF) transceiver. This micro-stimulator is very compact (18 mmx28 mm two layer printed circuit board) and light (5 g without battery), and can be carried on the back of a small animal to generate electrical stimuli according to the commands sent from a PC 10 meters away. The performance and effectiveness of the micro-stimulator were validated by in vitro experiments on the sciatic nerve (SN) of the frog, where action potentials (APs) as well as artifacts were observed when the SN was stimulated by the micro-stimulator. It was also shown by in vivo behavioral experiments on operant conditioned reflexes in rats which can be trained to obey auditory instruction cues by turning right or left to receive electrical stimulation ('virtual' reward) of the medial forebrain bundle (MFB) in a maze. The correct response for the rats to obey the instructions increased by three times and reached 93.5% in an average of 5 d. This micro-stimulator can not only be used for training small animals to become an 'animal robot', but also provide a new platform for behavioral and neurophysiological experiments.

Acoustic Stimulation↗

PubMed1975

Practical problems in the treatment of pain.

According to modern pain concepts, "pain" is the result of multifactorial influences. Planning of therapy therefore requires the diagnostic evaluation of a number of factors including delineation of an organic lesion, evaluation of the influence of pain on the individual's psychological development, situational anxiety, psychological coping style etc. The understanding and management of psychological factors is crucial in every pain syndrome as the idea the pain is either psychogenic or organic is outdated. For the treatment of mild pain salicylic acid is still unsurpassed. The rationale of its combination with a tranquillizer, and with codeine or benzomorphane for moderately severe pain, can be understood on the basis of modern pain concepts. Before strong narcotics are used a trial with combination of a phenothiazine with a tricyclic antidepressant drug is warranted. Methadone seems to have advantages over morphine for very distressing pain treated with narcotics. Biofeedback for pain due to muscle spasms, electrical stimulation of the dorsal column for intense chronic pain due to a well-delineated organic lesion, and operant conditioning applied by a well-trained team of physicians and staff are promising new treatments for pain. The place of acupuncture in future pain therapy cannot yet be judged. It must first be freed of cult-type opinions and evaluated further by studies meeting modern western standards of pain research.

Acupuncture Therapy↗

PubMed1989

Learned control of systolic blood pressure raising and lowering in rhesus monkeys.

Three male monkeys (Macaca mulatta) were operantly conditioned to raise and lower systolic blood pressure (SP). All animals were trained in three stages: first to lower, then to raise systolic pressure, and finally to alternate these two behaviors. All monkeys learned the task and performed reliably in all stages. Diastolic pressure (DP) usually paralleled systolic pressure but changed much less than SP. Heart rate (HR) always fell below baseline in lowering sessions, and in two of the three animals during raising sessions as well. These findings support our earlier results which showed that monkeys could learn to control heart rate. This animal model should permit detailed studies of the hemodynamic mechanisms mediating learned control of systolic pressure.

Animals↗

PubMed1979

Effects of solvents on schedule-controlled behavior.

Operant conditioning techniques have been shown to be sensitive to the acute effects of industrial solvents. In the first experiment, five rats trained in a multiple schedule with a fixed-ratio (FR) 10 component and a differential reinforcement of low rates (DRL) 20-sec component, with a time out 60-sec between reinforcement periods, were exposed to 0.25, 0.50, 1 and 2 ml of toluene in the experimental chamber. The effects were dose-dependent, with an increase in rate in the DRL component and a decrease in FR responding. A second experiment assessing the effects of chronic exposure to thinner in the acquisition of a timing behavior in rats showed an impairment in DRL learning after 4, 8 or 16 weeks of exposure to the solvent: however, rats having a resting period did not differ from control animals. Whereas this finding suggests a reversible impairment in the acquisition of a complex behavior, further research is needed to achieve more definitive conclusions.

Administration, Inhalation↗

PubMed1986

Enduring effects of prenatal diazepam on the behavior, EEG, and brain receptors of the adult cat progeny.

Pregnant cats were treated with a benzodiazepine receptor agonist, diazepam (DZ; Valium; average dose of 0.4 mg/kg/day, i.m.) between day 20 through day 53 of gestation in an attempt to alter the ontogenesis of the benzodiazepine receptors. As tested in fully developed one-year-old progenies, prenatal exposure to DZ resulted in a behavioral syndrome of hyperactivity, aggressiveness, behavioral signs of chronic anxiety, inability to habituate to novel environment, suppression or absence of the reward-induced alpha-like (7 to 11 Hz) electroencephalographic patterns during operantly conditioned behavior (bar pressing for 1 ml of milk reward), and deficits in the numbers of benzodiazepine receptors in the hypothalamus (-47%), fronto-orbital cortex (-33%) and postcentral cortex (-19%).

Agonistic Behavior↗

PubMed1988

Current psychological treatments for stress-related skin disorders.

Notable changes have been observed in the application of psychological therapies to medicine, including psychodermatology. This review article surveys current methods used by psychologists in the management of stress-related skin disorders, including hypnosis, relaxation training, biofeedback, operant conditioning, and cognitive-behavioral therapy. These techniques offer promise in the treatment of certain dermatologic conditions, but the limited amount of well-controlled and replicated studies of their use suggests that caution be taken in their application.

Behavior Therapy↗

PubMed1988

Control of sensory activation of granule cells in the fascia dentata by extrinsic afferents: septal and entorhinal inputs.

Three groups of rats were trained to perform a differential discrimination task in a 2-tone operant conditioning paradigm. One group received electrolytic lesions of the medial septal nuclei, another received electrolytic or knife cut lesions of the entorhinal cortex. These groups were compared with a normal control group. Recordings of granule cells in the fascia dentata were obtained in all animals during criterion performance of the behavioral task. Both lesions produced disruption of behavioral discrimination in the form of increased error and intertrial responding. Granule cell discharges to the tone stimuli were disrupted by each type of lesion. Septal lesions reduced the differential discharge tendency to CS+ and CS- and changed granule cell firing on all trials to statistically resemble firing on CS- trials in normal animals. Extensive lesions in the entorhinal cortex or knife cuts that severed the perforant path caused near elimination of the tone-evoked discharges to both the CS+ and CS-tones. Septal and entorhinal lesions caused marked changes in the sequential dependence of the granule cell discharge compared with intact animals. Results are discussed in terms of the control of the granule cell discharge by the remaining afferent pathways in each type of lesion condition.

Acoustic Stimulation↗

PubMed1987

Hearing in passerine and psittacine birds: a comparative study of absolute and masked auditory thresholds.

Operant conditioning and a psychophysical tracking procedure were used to measure auditory thresholds for pure tones in quiet and in noise for seven species of small birds--the budgerigar, canary, cockatiel, European starling, song sparrow, swamp sparrow, and the zebra finch. Audibility curves are roughly similar among the seven birds, with the maximum sensitivity between 2 and 5 kHz and poorer sensitivity outside this narrow region. Critical ratios (signal-to-noise ratio at masked threshold) were calculated from pure-tone thresholds in noise. Except for the budgerigar, the critical ratio functions of all birds increase at the rate of 3 dB/octave. This pattern is typical of that observed in most vertebrates. Critical ratios in the budgerigar, on the other hand, decrease gradually from 0.5 kHz to 2.8 kHz and increase dramatically above 2.8 kHz. The present research demonstrates that the critical ratio function for the budgerigar is not only different from other vertebrates but also different from other birds.

Animals↗

PubMedDate not supplied

Testing strategies in behavioral teratology: IV. Review and general conclusions.

Three laboratories collaborated to evaluate and compare different test concepts to be used for routine testing in behavioral teratology. Rat dams were treated orally with methylmercury starting two weeks prior to pairing until weaning of their offspring. In the first laboratory, the usual reproduction parameters were assessed in the dams, and all offspring (96-103 per group) were subjected to a routine developmental and behavioral test battery. After termination of the tests a random selection of these animals was further tested by multiparametric automated techniques in the other two laboratories. In one of these laboratories 12-13 males and females per group (one of each per litter) were tested in a visual discrimination reversal schedule, using nose-poking as operand. In the other laboratory the free behavioral of eight randomly selected males per dose group was studied in a wheel-shaped activity monitor with respect to locomotion magnitude and structure. In the same laboratory eight other males per group were trained in a discrete trial spatial alternation schedule, using lever press as operand. Both the developmental and behavioral testing battery as well as the automated techniques showed some significant effects in the offspring even at the low dose, where no reproduction effects had been noted. However, whereas the testing battery results were of unspecific nature, results of the automated techniques gave precise and specific information. In order to obtain optimal information, it is proposed to combine both approaches for routine testing. This combination could be achieved by using a balanced testing battery in young pups followed by an appropriate operant conditioning schedule in selected young adults.

Animals↗

PubMedDate not supplied

Comparison of the Collaborative Behavioral Teratology Study and Cincinnati Behavioral Teratology test batteries.

Comparison is made of the NCTR Collaborative Behavioral Teratology Study (CBTS) test battery with tests of the Cincinnati test battery using rat offspring derived from the same samples and sub-divided and evaluated in parallel. It was noted that in the two experiments, one using prenatal d-amphetamine and one prenatal methylmercury exposure, both test batteries were in general agreement, viz., d-amphetamine was largely negative with no major findings observed and methylmercury was positive with several major findings. The results obtained from the two test batteries differed, however, in the methylmercury experiments, undoubtedly as a reflection of the different tests used. Whereas the CBTS battery detected in each laboratory methylmercury-induced auditory startle facilitation, increased adult activity, and in all laboratories combined decreased correct responding and intertrial responding in operant conditioning, the Cincinnati battery found delayed righting and swimming ontogeny, decreased adolescent activity, and impaired complex water maze performance. It was noted that the CBTS battery emphasized startle and activity testing, while the Cincinnati battery emphasized reflex ontogeny. The CBTS battery convincingly demonstrated its detection sensitivity, intralaboratory and interlaboratory reliability, but since few positive control agents were evaluated relatively few data on criterion validity were obtained. The Cincinnati battery has relatively little data on its interlaboratory reliability, but a large amount of data on intralaboratory reliability, sensitivity, and through the use of many positive control agents in the past, considerable data establishing its criterion validity. All tests need all three characteristics, but validation is the most crucial task for future research on these and other test batteries.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗