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Results for “Conditioning, Operant”

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PubMed1999

Forebrain serotonin depletion facilitates the acquisition and performance of a conditional visual discrimination task in rats.

Three experiments examined the effects of depleting forebrain 5-hydroxytryptamine (5-HT) on the acquisition and performance of an operant conditional discrimination in the visual modality. In the first experiment, rats with 5-HT lesions induced by infusing the neurotoxin 5,7-dihydroxytryptamine intracerebroventricularly acquired the conditional visual discrimination more rapidly than the sham-operated controls. Following acquisition, a series of manipulations of the task parameters tested the effects of the lesion on cognitive, sensory and motivational aspects of performance. In experiment two, the performance of rats that had acquired the task to asymptote before receiving lesions was assessed. The performance of this second group of serotonin-lesioned rats was similar to that of the pre-acquisition lesioned group following all but one manipulation of the task parameters. When the rate of stimulus presentations was increased, rats with forebrain 5-HT depletions were protected from the disruptive effects on performance seen in the sham-operated controls. This latter finding was also observed in a third experiment, in which the infusion of the 5-HT1A receptor partial agonist, 8-hydroxy-2-(di-n-propylamino)tetralin (8-OHDPAT), directly into the dorsal raphe nucleus improved the performance of unlesioned rats following an increase in the rate of stimulus presentations. The results are discussed in terms of the behavioural, neurochemical and neuroanatomical specificity of serotonin function in appetitive learning and the implications for general theories of the function of serotoninergic processes in cognition.

Animals↗

PubMed1983

A participant modeling procedure to train parents of developmentally disabled infants.

Most of the procedures employed in parent training programs for handicapped children have been based on an operant conditioning model in general and contingency management procedures in particular. The purpose of the present study was to investigate the efficacy of a participant modeling procedure in training parents to work with their developmentally disabled infants. Fourteen such parents received training in which a therapist initially modeled the activities with the infant and then guided the parent as she or he mastered the procedures. Five developmentally disabled infants received a more traditional early intervention program in which the therapist provided all child training. The results indicated that those infants whose parents were trained by the participant modeling procedure evidenced significantly more developmental gains than those infants receiving traditional child training. The results suggest that cognitive behavioral procedures, such as participant modeling, are an alternative to strict operant procedures in training parents of handicapped children.

Behavior Therapy↗

PubMed1962

The operant control of vocalization in the dog.

Control over the vocal responses of three dogs was established using operant-conditioning procedures. Several points of interest were observed in the data. First, fixed-ratio schedules of reinforcement generated a vocal response topography which was similar in detail to that of a "motor" bar-nosing response. Second, vocal responding was brought under the control of external visual stimuli as a result of differential reinforcement. Third, good stimulus control was maintained on a multiple schedule containing a vocal-response component and a bar-response component. Fourth, the stimulus control on the multiple schedule transferred with minimal disruption to a chain schedule requiring a sequence of 10 bar responses followed by 10 vocal responses. Fifth, because vocal and bar responses are not mutually exclusive, concurrent responding tended to develop on the chain schedule. These results were discussed with reference to the advisability of applying the terms operant and respondent to unconditioned behavior, and, particularly, to unconditioned verbal behavior.

Animals↗

PubMed1997

Perception of synthetic /ba/-/wa/ speech continuum by budgerigars (Melopsittacus undulatus).

Other than humans, extensive vocal learning has only been widely demonstrated in birds. Moreover, there are only a handful of avian species that are known to be good mimics of human speech. One such species is the budgerigar (Melopsittacus undulatus), which is a popular mimic of human speech and learns new vocalizations throughout adult life. Using operant conditioning procedures with a repeating background task, we tested budgerigars on the discrimination of tokens from two synthetic /ba/-/wa/ speech continua that differed in syllable, but not transition, duration. Budgerigars showed a significant improvement in discrimination performance on both continua near the phonetic boundary for humans. Budgerigars also showed a shift in the location of the phonetic boundary with a change in syllable length, similar to what has been described for humans and other primates. These results on a nonmammalian species provide support for the operation of a general, nonphonetic, auditory process as one mechanism which can lead to the well-known stimulus-length effect in humans.

Adult↗

PubMed2006

Foundation and practice of neurofeedback for the treatment of epilepsy.

This review provides an updated overview of the neurophysiological rationale, basic and clinical research literature, and current methods of practice pertaining to clinical neurofeedback. It is based on documented findings, rational theory, and the research and clinical experience of the authors. While considering general issues of physiology, learning principles, and methodology, it focuses on the treatment of epilepsy with sensorimotor rhythm (SMR) training, arguably the best established clinical application of EEG operant conditioning. The basic research literature provides ample data to support a very detailed model of the neural generation of SMR, as well as the most likely candidate mechanism underlying its efficacy in clinical treatment. Further, while more controlled clinical trials would be desirable, a respectable literature supports the clinical utility of this alternative treatment for epilepsy. However, the skilled practice of clinical neurofeedback requires a solid understanding of the neurophysiology underlying EEG oscillation, operant learning principles and mechanisms, as well as an in-depth appreciation of the ins and outs of the various hardware/software equipment options open to the practitioner. It is suggested that the best clinical practice includes the systematic mapping of quantitative multi-electrode EEG measures against a normative database before and after treatment to guide the choice of treatment strategy and document progress towards EEG normalization. We conclude that the research literature reviewed in this article justifies the assertion that neurofeedback treatment of epilepsy/seizure disorders constitutes a well-founded and viable alternative to anticonvulsant pharmacotherapy.

Animals↗

PubMed1977

Drug discrimination and generalization in pigeons.

In a three-key operant conditioning situation six pigeons were trained to select the response key which was associated with each of three drug treatment conditions: d-amphetamine (2 mg/kg), pentobarbital (5 mg/kg), and saline. Thus, the drug state served as a discriminative stimulus for food reinforcement. After 20 sessions of discrimination training in each of the three conditions, more than 90% of the responses were correctly emitted in the presence of the appropriate drug or saline stimulus. Acquisition of the discrimination progressed at approximately equal rates for the three treatments. Subsequent to discrimination training, generalization gradients were obtained for several doses of the training drugs and for dose ranges of cocaine, morphine, and methocarbamol. The pigeons responded to morphine by choosing the key paired with pentobarbital during training; further, cocaine administration resulted in choice of the amphetamine key. However, metocarbamol, over the doses used, produced responding more characteristic of saline than of the other training drugs. The data suggest that a three-key operant discrimination procedure using pigeons provides a sensitive method for investigating the stimulus properties of relatively low doses of behaviorally relevant drugs.

Animals↗

PubMed1977

Behavioral system and apparatus for tone-detection and choice reaction times in the cat.

An efficacious operant-conditioning procedure for psychophysical experiments with cats is described. The system features (a) restraint of the cat and the use of the liquid reinforcement delivery cup to control orientation with respect to the stimuli, (b) a minimum of apparatus between the cat and a free-field sound source, (c) two response pedals so that separate "Yes" and "No" responses are defined, (d) a discrete trial procedure with reaction time (RT) defined as the time from the onset of a trial until the occurrence of a response, and (e) an effective liquid reinforcer and simple delivery system. Operation of the system was demonstrated with the method of constant stimuli. Detectability was directly related, and median RT for correct "Yes" responses inversely related, to tone sound pressure.

Animals↗

PubMed1986

Integration of learned and naturally occurring flexor EMG in the human step cycle.

Human locomotion, as a behavioral system, is well suited for investigating the interplay of learning with innate biological mechanisms. The present work assembled, from previous findings, a test battery of operant conditioning to modify strong ongoing electromyographic (EMG) activity of the left tibialis anterior (TA), an ankle flexor muscle. An EMG segment 100-400 msec long had to occur within 700 msec, and (in different training regimens) with filtered amplitude both above and below different thresholds--all in response to a colored light that flashed at a designated time in the step cycle. Reinforcement was a high or low tone that indicated success or failure, respectively. All four subjects met training criteria (90% success rate) at a moderate amplitude, just as had been true previously for a relatively inactive knee extensor. Subject-specific limitations were found in operant control at higher and lower amplitudes. New learning was not disruptive, although ipsilateral swing duration increased, nor was it phase-dependent on any portion of the step cycle.

Conditioning, Operant↗

PubMed1998

Effects of nitric oxide synthase inhibitor NG-nitro-L-arginine methyl ester on spatial and cued leaning.

An investigation was made of the effects of the nitric oxide synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME) on the acquisition and retention of two operantly conditioned discrimination tasks. Twenty Long-Evans rats were conditioned to approach one of two spatial locations that was either held constant across trials (spatial task) or was associated with a visual cue (illuminated lamp) that was randomly assigned to one of the locations on each trial (cued task). Rats were assigned to one of two treatment groups in which they received intraperitoneal injections of either NG-nitro-L-arginine methyl ester or saline approximately 2 h before sessions on each day of training. Analysis was made of the trial-by-trial performance in order to identify the characteristics of learning under each condition. Assessment of learning acquisition was based on the number of trials required to reach a criterion of 80% correct responses, whereas retention was assessed by the number of trials to criterion on each day after the criterion was initially reached. Analysis indicated that treatment groups did not differ significantly on acquisition or retention of either the spatial or cued task. These results indicate that inhibition of nitric oxide synthase does not interfere with the learning or retention of basic operant tasks that involve simple spatial or visual analysis. Whereas results from biochemical and physiological investigations have suggested an impact of nitric oxide synthase on behavioural function, behavioural investigations indicate a limited impact of nitric oxide synthase inhibition on learning and memory. Although these results do not discount the role of nitric oxide synthase in a hippocampal mechanism, they illustrate that behavioural analysis should be made in the context of multiple interacting neural systems. Viewed with previous behavioural research on the effects of NG-nitro-L-arginine methyl ester, these results indicate that nitric oxide synthase inhibition results in impairment of certain forms of learning whereas other forms are preserved.

Animals↗

PubMedDate not supplied

[Conditioning of affect-induced breath-holding spells].

Breath holding spells often arise in the context of affectively dramatic conflict situations between mother and child. Assessment by psychopathological screening instruments, however, has not given empirical evidence of an increased psychiatric morbidity in these children. Therefore, in our study we did not concentrate on basic psychopathology but on behavioral variables that might be effective during the ongoing attack episode and, hereby, exert an influence on the risk of chronification (relapse rate). The main goal of this approach is to examine secondary reinforcement effects on the attack behavior according to the learning principle of operant conditioning. Our sample consisted of 28 children and ten siblings as control group. To control for effects of behavioral disorders in the sample, we applied the Marburger Verhaltensliste (MVL) on the level of the child, and the Familienfragebogen (FFBO-III) on the level of family adaptation. The main assessment instrument, however, was the Functional Behavior Analysis (FBA) in order to measure the trigger, reaction and consequence conditions in the course of given attack episodes. MVL and FFBO-III results confirm the lack of basic psychopathology in the patients and their families. The individualized FBA's can be transformed in a taxonomy of five distinct types. All the first three types are triggered by intensive conflict situations and show a high relapse rate (type 1) if the mother reacts in a rewarding manner with positive consequences for the child (reinforcement condition), a dramatically reduced rate (type 2) if the mother reacts neutral (extinction condition), or a heterogeneous pattern (type 3) if the mother reacts punishing (punishment condition). In type 4 (pallid type) and type 5 (triggered spontaneously), respectively, no responsiveness to conditioning effects can be recognized. With respect to parent counselling, a recommendation for a quiet and consequent reaction can be concluded, especially in the case of a preceding conflict situation. The empirical results are integrated into a hypothetical model on pathogenesis that delineates the interaction of neurophysiological and behavioral factors in the maintenance of breath-holding spells.

Apnea↗

PubMedDate not supplied

[The influence of BT-melanin on the recovery of conditioned instrumental reflexes in rats surviving after ablation of the sensorimotor cortex].

It has been shown the reinforcement of the corticofugal plasticity in adult rats after unilateral ablation of sensorimotor cortex accompanied by intramuscular injections of low concentrations of BT-melanin. In result the process of compensatory recovery in rats central nervous system is accelerated, confirmable by the rapid recovery of previously elaborated instrumental conditioned reflex in comparison with the control animals. It is assumed that the compensation of the motor deficit arised after the sensorimotor cortex ablation is ensured by the ability of two main motor systems of the brain (corticospinal and corticorubrospinal) to duplicate each other. This phenomenon of functional switching of descending influences has also been revealed in control group rats, not injected with BT-melanin. However the difference in time periods of operantly conditioned reflex recovery, for experimental and control groups, argues the apparent acceleration of this process, induced by the effects of BT-melanin. The obtained data considers the possibility of applied use of low concentrations of BT-melanin.

Animals↗

PubMedDate not supplied

Assessment of the high-frequency components of brain electrical activity using inhomogeneity indexes.

Inhomogeneity indexes were developed, and were found to be quite reliable indicators of the presence of short-term high-frequency bursts in the electrical activity of the dog brain, and were also sensitive discriminators of quasi-homogeneous fragments in terms of the level of "general activation." Studies demonstrated that the values of these coefficients reflect the individual features of animal brain electrical activity, as well as its dynamics during the development of conditioned operant feeding reflexes. At the same time, these indexes did not reveal any regional variations. Using the construction of an inhomogeneity spectrum as an example, an approach to identifying similar numerical characteristics, also based on traditional harmonic analysis (Fourier transformation), is discussed.

Animals↗

PubMed1976

[Behavior therapy in disorders of dietary behavior].

Behaviour therapies using conditioning principles have been successful in the treatment of some psychopatological eating behaviours. Such have been the cases for anorexia nervosae in adolescents and adults, refusal to eat in the young child and difficulties of swallowing. Some of these cases are described. Research has been done in different countries on the applications of these methods to the treatment of obesity caused by overeating which appears very frequently in our societies. Systematic and covert desensitization and operant conditioning using positive reinforcements are more frequently used in these behaviour modification procedures than aversive methods. More recently, researches on self-control (self-reward and self-punishment) have shown it as a very efficient tool for inducing weight loss. These methods using self-control have been applied to large populations: after a first, careful examination of the patient's eating behaviour, the program of reinforcement is established. It can be partially controlled by written instructions and letters. Results are already encouraging although they need to be followed up. But more research should be done on overeating behaviours, the way they appear and are maintained and on different programs of reinforcement for weight loss.

Adolescent↗

PubMed1985

A comparison of peripheral and central effects of CCK8 on water-reinforced operant responding.

Systemic administration of cholecystokinin-octapeptide (CCK8) suppresses operant responding in water deprived rats, but it is unclear whether this effect is centrally or peripherally mediated. Rats were trained to press a lever for water in an operant conditioning chamber under a variable-interval schedule of reinforcement. After response rate stabilized injections were administered, and response suppression was measured by comparing injection response rate to baseline rate. Intracerebroventricular injections of CCK8 reduced lever pressing at relatively high doses (20 and 50 micrograms/rat). But in a direct comparison, the same dose of CCK8 (20 micrograms/rat) given intraperitoneally reduced responding significantly more than when given into the lateral ventricle. The suppressive effects of CCK8 (30 and 300 micrograms/kg i.p.) were significantly reduced by complete abdominal vagotomy. The effects of CCK8 (30 micrograms/kg i.p.) were blocked by pretreatment with the specific competitive CCK8 antagonist dibutyryl cyclic GMP (70 and 140 mg/kg i.p.), but not by the acetylcholine antagonist atropine (0.1 to 10 mg/kg i.p.). These data suggest that suppression by CCK8 of operant lever pressing in water-deprived rats is primarily mediated by vagal afferent fibers.

Animals↗

PubMed1976

Effects of intraventricular glutamic acid on the acquisition, performance, and extinction of an operant response, and on general activity.

This study was designed to investigate the effects of intracerebral injections of glutamic acid on acquisition and extinction of a bar-press response, performance of that response, and behavior activity. Nineteen food-deprived rats bearing chronic ventricular cannulae were tested in operant conditioning chambers or in an open field. Just prior to each testing session each animal was injected intraventricularly with 10 mul of either normal or acidified saline solution (control groups), or 10 mul of 100 mMol glutamic acid solution. Acquisition of the bar-pressing response by the glutamic acid group was significantly retarded as compared to the control groups, and the responding of the glutamic acid group was suppressed during the beginning of the first few sessions of testing on a fixed-interval schedule and during extinction. Other behavioral measures, such as operant level, performance of the response on a continuous schedule, performance on fixed-interval and extinction schedules except during the start of the first few sessions, and behavioral activity, were either unaffected or only slightly affected. It is concluded that interference with the normal neurophysiological activity of glutamic acid in the central nervous system interferes with learning and suppresses behavioral output in certain situations.

Animals↗

PubMed1997

High-amplitude sucking and newborns: the quest for underlying mechanisms.

This study seeks to determine whether newborns are sensitive to an operant-conditioning task involving an unprepared relation between a response and a stimulus. The High-Amplitude Sucking procedure, which is based on such a relation by reinforcing nonnutritive sucking with auditory stimulation, was used. In order to verify that newborns learn the contingency between sucks and sounds in the HAS paradigm, three experiments were carried out. In Experiment 1, the effect of contingent versus noncontingent presentation of speech sounds on newborns' sucking activity was investigated during the minutes following a silent baseline. In contrast to what has been reported with 2-month-old infants in HAS, contingently stimulated newborns did not differ significantly from a nonstimulated control group. Experiment 2 showed that an increase in sucking rates could be obtained after a stimulus change, when sounds were presented contingently, but not when sounds were presented noncontingently. Experiment 3 demonstrated that newborns' sucking responses were reinforced by variation in the presented speech sounds. The results of these three experiments support the hypothesis that newborns tested under the HAS procedure are involved in an operant-learning situation. Implications for learning in neonates and possible differences with older infants are discussed.

Child, Preschool↗

PubMed1992

Responses of monkey dopamine neurons during learning of behavioral reactions.

1. Previous studies have shown that dopamine (DA) neurons respond to stimuli of behavioral significance, such as primary reward and conditioned stimuli predicting reward and eliciting behavioral reactions. The present study investigated how these responses develop and vary when the behavioral significance of stimuli changes during different stages of learning. Impulses from DA neurons were recorded with movable microelectrodes from areas A8, A9, and A10 in two awake monkeys during the successive acquisition of two behavioral tasks. Impulses of DA neurons were distinguished from other neurons by their long duration (1.8-5.0 ms) and low spontaneous frequency (0.5-7.0 imp/s). 2. In the first task, animals learned to reach in a small box in front of them when it opened visibly and audibly. Before conditioning, DA neurons were activated the first few times that the empty box opened and animals reacted with saccadic eye movements. Neuronal and behavioral responses disappeared on repeated stimulus presentation. Thus neuronal responses were related to the novelty of an unexpected stimulus eliciting orienting behavior. 3. Subsequently, the box contained a small morsel of apple in one out of six trials. Animals reacted with ocular saccades to nearly every box opening and reached out when the morsel was present. One-third of 49 neurons were phasically activated by every door opening. The response was stronger when food was present. Thus DA neurons responded simultaneously to the sight of primary food reward and to the conditioned stimulus associated with reward. 4. When the box contained a morsel of apple on every trial, animals regularly reacted with target-directed eye and arm movements, and the majority of 76 DA neurons responded to door opening. The same neurons lacked responses to a light not associated with task performance that was illuminated at the position of the food box in alternate sessions, thus demonstrating specificity for the behavioral significance of stimuli. 5. The second task employed the operant conditioning of a reaction time situation in which animals reached from a resting key toward a lever when a small light was illuminated. DA neurons lacked responses to the unconditioned light. During task acquisition lasting 2-3 days, one-half of 25 DA neurons were phasically activated when a drop of liquid reward was delivered for reinforcing the reaching movement. In contrast, neurons were not activated when reward was delivered at regular intervals (2.5-3.5 s) but a task was not performed.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

PubMed1978

Menstrual cycle influences on operant behavior of female rhesus monkeys.

Nine female rhesus monkeys were paired with males throughout 63 menstrual cycles. The females' motivation to approach males was studied with an operant conditioning paradigm that required the female to press a lever 250 times to gain access to the male. Sexual behavior was scored during standard 60-min tests that followed the attainment of access (17 pairs, 1,440 tests). In the overall data, mean times to access were shortest at mid-cycle and longest just before and after the onset of menstruation, and a model-fitting method showed that 45% of cycles from individual pairs were significantly correlated with a V-shaped model of the overall pattern. Male sexual activity was highest at mid-cycle and lowest in the last quarter of the cycle, but the changes in access times could not be attributed entirely to the rewarding effects of the ejaculations. In the combined data from five females (9 pairs, 33 cycles), high estradiol levels and low progesterone levels were statistically associated with short access times and short ejaculation times. The overall effect was for operant performance and sexual activity to be synchronized and maximized in the periovulatory period of the menstrual cycle.

Animals↗