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The association of chlorpromazine with Absinthium and Mace oils has been studied on rat's operant conditioning behaviour. Mace oil at the lowest doses showed a non competitive antagonism versus chlorpromazine; Absinthium oil didn't modify the effects of chlorpromazine.
Cardioacceleration produced by operant conditioning was associated with elevation of plasma renin activity. This study suggests that emotional stimuli, which produce cardioacceleration, may also cause increased renin secretion, thus providing a mechanism by which factors operating through the mind and sodium intake could summate in the production of hypertension.
Aerial respiration of the pond snail, Lymnaea stagnalis, can be operantly conditioned; however, the parameters necessary to produce long-term (LTM) or intermediate term memory (ITM) have not previously been investigated. We conducted training using procedures that varied in the duration of the training session, the number of training sessions per day or the amount of time between subsequent training sessions (SI). We found that by varying the duration and frequency of the training session learning could be differentially produced. Furthermore, the ability to form LTM was dependent not only on the duration of the training session was also the interval between training sessions, the SI. Thus it was possible to produce ITM, which persists for up to 3 hr, and not form LTM, which persists at least 18 hr. Learning, ITM, and LTM can be differentially produced by altering the SI, the duration of the training session, or the number of training sessions per day. These findings may allow us to begin to elucidate the underlying neural mechanisms of learning, ITM, and LTM.
The present investigation was designed to study the relationships between extraversion, d-amphetamine and modes of reinforcement in verbal operant conditioning. A factorial design involving two levels of extraversion (extraverts and introverts), two reinforcement conditions ('good' and 'electric shock') and three treatments (placebo and two doses, 7.5 and 12.5 mg, of d-amphetamine) with repeated measures on the last factor was used. Sixty postgraduate female students were individually subjected to Taffel's verbal conditioning procedure. The study supported the following conclusions: (1) under the placebo condition, the extraverted subjects condition better with the rewarding reinforcer while the introverted subjects condition better with the punishing reinforcer; (2) under the influence of d-amphetamine, the extraverted subjects condition better with the punishing reinforcer while the conditioning scores of introverted subjects decrease with the punishing reinforcer but are not influenced with the rewarding reinforcer.
OBJECTIVE: To study the association between hospitals' operating conditions and the risk of early readmission. The hypothesis was that high patient turnover might lead to a rise in the risk of readmission soon after discharge (within 30 days). METHOD: A multivariate model including hospital and patient variables was tested using Cox's regression analysis, adjusting for clustering effects. The material included data from 20 hospitals, with 5,520 patients in the final model. RESULTS: High patient turnover (annual discharges per bed) was significantly associated with an increased risk of readmission (hazard ratio (HR)= 3.37 (95% CI = 2.39-4.75)). In addition, being discharged from a ward with relatively low access to therapists increased the hazard further. CONCLUSION: High patient turnover at the discharging ward was found to increase the patients' hazard of early readmission. This observation supports the hypothesis of a link between the operation conditions of the hospitals and patient outcome on a short time-scale.
The present report presents evidence that operant conditioning processes may contribute to hypokinetic effects in rats induced by repeated haloperidol (HAL) treatments. Twenty-four male Sprague-Dawley rats were subdivided into three equal groups and given 9 daily injections of either 0.1 or 1.0 mg/kg HAL, i.p., or the lactic acid vehicle 1 h before testing of motoric behavior. The effects of the HAL were dependent upon dose and the test situation. In an open field, 1.0 HAL produced a complete akinesia whereas 0.1 HAL initially had no effect, but with repeated treatments the 0.1-HAL-treated rats became hypokinetic. When the animals were tested for their response to enter a dark compartment, the 2 doses had equivalent effects. Initially, HAL had no effect, but with repeated treatments, latencies to enter the dark compartment increased at the equivalent rates for the 0.1 and 1.0 HAL groups. When conditioned drug effects were assessed following withdrawal, only in drug environment situations which operant behavior occurred initially did hypokinesia persist. These results are relevant to understanding the delayed onset of action and antipsychotic effects of neuroleptic drugs.
Corticosterone was injected bilaterally into the dorsal hippocampus of BALB/c Mice immediately after the first extinction session of an operant conditioning in a Skinner box. Compared with the control animals the Mice that received 1 or 0.1 microgram corticosterone exhibited 24 hrs. later, faster extinction of this conditioning. With a 0.01 microgram dose of corticosterone in each hippocampus we obtained an accelerated extinction during the session. These data suggest that corticosterone modulates hippocampal mechanisms involved in memory processes.
The breakthrough behavior of Pb2+ in an ETS-10 fixed bed was experimentally examined at various operating conditions. Results showed that the adsorption amount of Pb2+ ions per unit mass of ETS-10 particles in a column is about 1.68 mmol/g under the experimental conditions. This amount was not markedly affected by the operating conditions because of the rapid adsorption rate of Pb2+ ions on ETS-10. In the presence of competitive metal ions, the amount of Pb2+ adsorbed on ETS-10 was slightly reduced. An overshoot of the effluent concentrations of competitive metal ions Cu2+ and Cd2+ was observed in the adsorption systems of binary and ternary solutions. This is ascribed to the replacement of pre-adsorbed Cu2+ and Cd2+ ions by Pb2+ ions. The ETS-10 column broken up by Pb2+ ions can be regenerated by using an EDTA-Na2 solution and the regenerated column can be reused.
The aeration systems of two full-scale, activated-sludge basins were compared during a period of three years, under the same operating conditions, using dynamic offgas testing. Only the material of the diffuser was different (membrane versus ceramic-tube diffusers). The investigation has shown that, although the membrane diffusers have higher initial standard-oxygen-transfer efficiency (alphaSOTE) and standard-aeration efficiency (alphaSAE), these decreased over time, while the alphaSAE of the ceramic diffusers started lower, but increased slightly over the whole period. A cost comparison makes clear how important it is to evaluate the aeration system under process conditions. The operating costs were the dominant factor (approximately 10x higher than capital costs), and operating costs were approximately 20% higher for membrane versus ceramic diffusers. The poor performance of the membrane-tube diffusers under process conditions could be explained on the basis of the actual alphaAE values in the basin, not the standardized values.
The prisoner's dilemma (PD) is the leading metaphor for the evolution of cooperative behavior in populations of selfish agents. Although cooperation in the iterated prisoner's dilemma (IPD) has been studied for over twenty years, most of this research has been focused on strategies that involve nonlearned behavior. Another approach is to suppose that players' selection of the preferred reply might be enforced in the same way as feeding animals track the best way to feed in changing nonstationary environments. Learning mechanisms such as operant conditioning enable animals to acquire relevant characteristics of their environment in order to get reinforcements and to avoid punishments. In this study, the role of operant conditioning in the learning of cooperation was evaluated in the PD. We found that operant mechanisms allow the learning of IPD play against other strategies. When random moves are allowed in the game, the operant learning model showed low sensitivity. On the basis of this evidence, it is suggested that operant learning might be involved in reciprocal altruism.
The design and operating conditions of an outdoor replicated stream system are described. The facility is composed of a long inlet stream, a header weir which diverts inflowing water to six artificial stream channels (each 45 m long and 40 cm wide), a settlement pond at the end of the channels, and an outlet stream which diverts the water back to an irrigation channel. Flow regulation is achieved by "V-notched" gates at the head of each stream and depth by a second set of gates at the end of each stream. Physicochemical conditions were monitored over a 260-day period and even though significant temporal variation was detected, little between-stream variation was observed for most parameters. Small, but significant, between-stream differences in dissolved oxygen and pH were detected but were attributed to sampling procedure rather than real between-stream differences. A relatively rich invertebrate fauna colonized the streams. Invertebrate densities increased rapidly after initiation of flow and stabilized after 38 days. Chironomoid midge larvae were numerically the most important taxa, although the proportion of total density contributed by this group changed significantly with time. Taxon richness, chironomid taxon richness, diversity, and eveness also increased with time until a stable point was reached after 90 days of flow. No significant between-stream difference in any of these parameters was detected suggesting that colonization dynamics were similar in each stream.
Eight epileptic patients with mixed seizures refractory to medical control participated in a double-blind crossover study to determine the effectiveness of operant conditioning of the EEG as an anticonvulsant procedure. Baseline levels of seizures were recorded for four months prior to the beginning of treatment. Participants then received false (noncontingent) feedback for two months followed by an ABA-patterned training program lasting a total of ten months. Subjects were assigned to three treatment groups based on different schedules of EEG feedback. They were first trained (A1 phase) either to suppress slow activity (3 to 8 Hz), to enhance 12- to 15-Hz activity, or to simultaneously suppress 3- to 8-Hz and enhance 11- to 19-Hz activity. This was followed by a B phase, in which patients were trained to enhance slow activity (3 to 8 Hz). In the final phase (A2), the initial training contingencies were reinstated. Neuropsychological tests were performed before and after training, and changes in EEG activity as determined by Fast Fourier spectral analyses were analyzed. Five of eight patients experienced a decrease in their mean monthly seizure rate at the completion of feedback training as compared with their initial baseline level.
Two baboons were prepared with arterial and venous catheters and their heart rate and blood pressure were monitored continuously thereafter. Following a 2 to 3 week interval during which baseline cardiovascular levels were determined, the animals were exposed to daily 12 hr conditioning sessions (alternating with 12-hr "rest" or "Conditioning Off" sessions) during which fool reward and shock-avoidance were programmed as contingent consequences of pre-specified increases in heart rate. Initially, the criterion heart rate was set at 10-15 bpm above the animal's pre-experimental resting baseline level, with progressive increases programmed to occur at a rate approximating 7 bpm per week over a period of 8-10 weeks. Within this 2-3 month interval, heart rate doubled, reaching levels maintained above 160 bpm for more than 95% of each daily 12-hour "Conditioning On" period. Propranolol selectively eliminated the conditioned heart rate increase but not the blood pressure elevation, indicating the contribution of sympathetic nervous activity to these operantly conditioned cardiovascular changes.
This study was designed to examine the changes in the modulation of small populations of cerebellar neurons during the acquisition of a complex, operantly conditioned forelimb task in cats. The experiments are based on the general postulate that, during the learning of a complex motor behavior, the cerebellum is important for generating a coordinated movement that meets the task's objectives, and that, as the cerebellum participates in this process, it acts to reinforce the effective motor pattern once it has been established. This specific study examines whether the changes in the modulation of cerebellar nuclear neurons during the learning of this task are consistent with this view. Cats were required to learn to move the manipulandum through a novel pattern of 2-3 consecutive straight grooves connected end to end in different spatial configurations, e.g., the letter L, an inverted L, and the letter C. Throughout the acquisition process, 6-12 single units were recorded simultaneously in the cerebellar nuclei, and the kinematics of the movement were evaluated using an Optotrak system. Cells were recorded from the two interposed nuclei and the dentate nucleus in these initial studies. Trials were sorted off-line based on the level of skill at which the required movement was performed. This was assessed using several objective criteria such as movement times, kinematic characteristics, and smoothness (number of peaks in the velocity profile). Event-related histograms then were constructed from each group of sorted trials. Changes in modulation related to a specific event were measured in successive histograms for each neuron.(ABSTRACT TRUNCATED AT 250 WORDS)
Empirical and theoretical reasons were given to investigate operant conditioning in a new, integrative approach within motor control physiology. Elements of inborn and learned behavior were presented in a framework specifying their stimuli and responses. The operant was redefined as a controlling discriminative stimulus, Sd, together with the response, R, it produces, on the basis of a previous literature of operant and instrumental research. Complex motor and neural activity were reviewed in accordance with partitioning of: responses, controlling stimulation, reinforcement, and functions of movement-produced stimulation. Schematics portrayed reinforcement principles through analysis of a fast pathway from Ia muscle spindle afferents to motor outflow. Methods were suggested to minimize operant units through selective reinforcement and establish them to defined end points of learning within composite, ongoing behavior. It was argued that operant neural mechanisms can be investigated efficiently only by starting with individual operants that are thoroughly characterized.
Monkeys are able to increase or decrease triceps surae H-reflex when reward depends on reflex amplitude. Operantly conditioned change occurs over weeks and produces persistent alterations in the lumbosacral spinal cord which should be technically accessible substrates of primate memory. Previous work monitored and conditioned triceps surae H-reflex in one leg. To determine whether H-reflex conditioning in one leg affects the control leg, the present study monitored H-reflexes in both legs while the reflex in one leg underwent HR increases or HR decreases conditioning. Under the HR increases mode, H-reflex increase was much greater in the HR increases leg than in the control leg. Under the HR decreases mode, H-reflex decrease was confined to the HR decreases leg. By showing that conditioning of one leg's H-reflex produces H-reflex asymmetry, the data further define the phenomenon and indicate that the other leg can serve as an internal control for physiologic and anatomic studies exploring the sites and mechanisms of the spinal cord memory substrates.
Bursts of high-frequency (HF, 80-90 Hz, 70-80 microV) oscillations in the electrical activity (EA, 1-200 Hz) of the dog neocortex were studied during operant conditioning. These bursts of HF oscillations appeared in the EA of interstimulus intervals at the generalization stage on a background of dominant oscillations of lower frequency and amplitude (10-40 microV). Use of a new strategy for primary analysis of EA production (specifically, a coefficient of inhomogeneity) allowed amplitude-frequency inhomogeneity of the EA to be estimated, with isolation of bursts of HF oscillations. Use of an original nonharmonic analysis, consisting of expansion of EA waves into a system of half-waves which were used to construct distribution maps, revealed the regional properties of bursts of HF oscillations. The results of these investigations supplement previous data obtained using other methodological approaches (Fourier transformation and spectral density factor analysis). The properties of bursts of HF oscillations observed here provide evidence for the differential involvement of cortical areas (even close-lying areas separated by distances of 3-5 mm) in the spatial-temporal organization of potentials typical of this conditioning paradigm.
A PDP-12 interface was designed, constructed, and tested for realtime imput and output of binary information. Within limits this interface can be used with any peripheral device which operates in the binary mode. In addition to its generality of application the interface features include ease of expansion and low cost. A description of its design and operation is give here is terms of a typical application: the control of behavioral equipment (i.e. "Skinner Boxes") for operant conditioning.