bluuebunny/crossref_metadata_2025 huggingface dataset:
OBSERVING BEHAVIOR IN A COMPUTER GAME
Authors: Case David A. , Ploog Bertram O. , Fantino Edmund
Published: March 2006

Contingencies studied in lever‐pressing procedures were incorporated into a popular computer game, “Star Trek,” played by college students. One putative reinforcer, the opportunity to destroy Klingon invaders, was scheduled independently of responding according to a variable‐time schedule that alternated unpredictably with equal periods of Klingon unavailability (mixed variable time, extinction schedule of reinforcement). Two commands (“observing responses”) each produced stimuli that were either correlated or uncorrelated with the two components. In several variations of the basic game, an S‐, or bad news, was not as reinforcing as an S+, or good news. In addition, in other conditions for the same subjects observing responses were not maintained better by bad news than by an uninformative stimulus. In both choices, more observing tended to be maintained by an S— for response‐independent Klingons when its information could be (and was) used to advantage with respect to other types of reinforcement in the situation (Parts 1 and 2) than when the information could not be so used (Part 3). The findings favor the conditioned reinforcement hypothesis of observing behavior over the uncertainty‐reduction hypothesis. This extends research to a more natural setting and to multialternative concurrent schedules of events of seemingly intrinsic value.
DEVELOPMENT OF CONDITIONAL AND EQUIVALENCE RELATIONS WITHOUT DIFFERENTIAL CONSEQUENCES
Authors: Harrison Richard J. , Green Gina
Published: March 2006

Two experiments were conducted to establish conditional stimulus relations without differential consequences and to test for the emergence of other relations. In Experiment 1, 3 adults responded to match‐to‐sample displays in which sample‐comparison pairs were constant while the second comparison presented with each pair changed periodically across trials. No differential consequences followed any comparison selections. All subjects learned conditional relations between constant samples and comparisons, but results of tests for transitivity in those relations were equivocal. In Experiment 2, 4 children were given unreinforced training and testing similar to that provided to the adults in Experiment 1, with procedural refinements. One child learned conditional relations and demonstrated emergent relations that confirmed the development of two four‐member equivalence classes. Another child learned the conditional relations but did not demonstrate any emergent relations reliably. A 3rd child, after reinforced training on two conditional relations, learned four new conditional relations without differential consequences and demonstrated symmetry but not equivalence in the trained relations. The 4th child did not learn the conditional relations. These findings emphasize the importance of careful construction of tests for stimulus equivalence and suggest a need for critical analyses of the apparent emergence of untrained stimulus relations on unreinforced tests that has been observed in several stimulus equivalence studies.
CONDITIONAL DISCRIMINATION IN MENTALLY RETARDED ADULTS: THE DEVELOPMENT OF GENERALIZED SKILLS
Authors: Saunders Kathryn J. , Spradlin Joseph E.
Published: March 2006

The development of generalized conditional discrimination skills was examined in adults with retardation. Two subjects with histories of failure to acquire arbitrary matching under trial‐and‐error procedures were successful under procedures that trained one or more prerequisite skills. The successive discrimination between the sample stimuli was established by training the subjects to name the stimuli. The simultaneous discrimination between the comparison stimuli was established using either (a) standard simple discrimination training with reversals or (b) a procedure in which each of the two sample‐comparison relations in the conditional discrimination was presented in blocks of trials, with the size of the blocks decreasing gradually until sample presentation was randomized. The amount of prerequisite training required varied across subjects and across successive conditional discriminations. After acquiring either two or three conditional discriminations with component training, both subjects learned new conditional discriminations under trial‐and‐error procedures. In general, each successive conditional discrimination was acquired more rapidly. Tests showed that conditional responding had become a generalized skill. Symmetry was shown for almost all trained relations. Symmetry trial samples were ultimately named the same as the stimuli to which they were related in training.
EFFECTS OF RESPONSE VARIABILITY ON THE SENSITIVITY OF RULE‐GOVERNED BEHAVIOR
Authors: Joyce James H. , Chase Philip N.
Published: March 2006

Two experiments examined the relation between response variability and sensitivity to changes in reinforcement contingencies. In Experiment 1, two groups of college students were provided complete instructions regarding a button‐pressing task; the instructions stated “press the button 40 times for each point” (exchangeable for money). Two additional groups received incomplete instructions that omitted the pattern of responding required for reinforcement under the same schedule. Sensitivity was tested in one completely instructed and one incompletely instructed group after responding had met a stability criterion, and for the remaining two groups after a short exposure to the original schedule. The three groups of subjects whose responding was completely instructed or who had met the stability criterion showed little variability at the moment of change in the reinforcement schedule. The responding of these three groups also was insensitive to the contingency change. Incompletely instructed short‐exposure responding was more variable at the moment of schedule change and was sensitive to the new contingency in four of six cases. In Experiment 2, completely and incompletely instructed responding first met a stability criterion. This was followed by a test that showed no sensitivity to a contingency change. A strategic instruction was then presented that stated variable responding would work best. Five of 6 subjects showed increased variability after this instruction, and all 6 showed sensitivity to contingency change. The findings are discussed from a selectionist perspective that describes response acquisition as a process of variation, selection, and maintenance. From this perspective, sensitivity to contingency changes is described as a function of variables that produce response variability.
SKINNER'S VERBAL BEHAVIOR, CHOMSKY'S REVIEW, AND MENTALISM
Authors: Stemmer Nathan
Published: March 2006

Skinner's Verbal Behavior (1957) is a comprehensive treatise that deals with most aspects of verbal behavior. However, its treatment of the learning of grammatical behavior has been challenged repeatedly (e.g., Chomsky, 1959). The present paper will attempt to show that the learning of grammar and syntax can be dealt with adequately within a behavior‐analytic framework. There is no need to adopt mentalist (or cognitivist) positions or to add mentalist elements to behaviorist theories.
DELAYED AND CURRENT STIMULUS CONTROL IN SUCCESSIVE DISCRIMINATIONS
Authors: White K. Geoffrey
Published: March 2006

In a successive discrimination in which successively alternating red and green hues signaled component variable‐interval schedules, sensitivity of the ratio of responses in the two components to variation in the component reinforcer ratio decreased systematically during the course of the component. This decrease in stimulus control or discrimination over the course of the component was shown to be the result of delayed control of responding during the component by the stimulus transition between components. When the red‐green stimulus transition was altered by interpolating a white stimulus at the end of each 60‐s component, discrimination at the beginning of the component (measured by the power‐function exponent for sensitivity to reinforcement) was reduced. Conditions with the white stimulus inserted in other quarters of the component indicated that the current discriminative stimulus exerts control over responding throughout the component, whereas during about the first half of the component, response differentials are influenced by the transition between discriminative stimuli.
ADDITIONAL‐DELAY SCHEDULES: A CONTINUUM OF TEMPORAL CONTINGENCIES BY VARYING FOOD DELAY
Authors: Manabe Kazuchika
Published: March 2006

Pigeons performed on discrete‐trial, temporally defined schedules in which the food delay (D) was adjusted according to the latency of the key peck (X) and two schedule parameters (t and A). The schedule function was D = A(t ‐ X), where D is the experienced delay between a response and a reinforcer. The schedule parameter t is the maximum value below which the present contingencies occur. A is the additional delay to reinforcement for each second the response latency is shorter than the t value. When A = 0 s, the schedule is a continuous reinforcement schedule with immediate reinforcement. When A = 1 s, the schedule is a conjunctive fixed‐ratio 1 fixed‐time t‐s schedule. When A approaches infinity, the schedule becomes a differential reinforcement of long latency schedule. The latencies for subjects with t = 10 s and t = 30 s were observed with the present schedules having seven values for A between 0 s and 11 s. In addition, the latencies for subjects for which t = 30 s were observed at an A value of 31 s to 41 s. As the A value increased, the latencies approached the t value for subjects for which t = 10 s. The latencies for 30‐s‐t subjects did not approach t, even when the A value was 41 s. The latencies for 10‐s‐t subjects at 11‐s A value were longer than those under yoked conditions having exactly the same delays/interreinforcement intervals. These results demonstrated a continuum of latency related to the schedule continuum (value of A) at a small t value.
MULTIPLE DETERMINANTS OF THE EFFECTS OF REINFORCEMENT MAGNITUDE ON FREE‐OPERANT RESPONSE RATES
Authors: Reed Phil
Published: March 2006

Four experiments examined the effects of increasing the number of food pellets given to hungry rats for a lever‐press response. On a simple variable‐interval 60‐s schedule, increased number of pellets depressed response rates (Experiment 1). In Experiment 2, the decrease in response rate as a function of increased reinforcement magnitude was demonstrated on a variable‐interval 30‐s schedule, but enhanced rates of response were obtained with the same increase in reinforcement magnitude on a variable‐ratio 30 schedule. In Experiment 3, higher rates of responding were maintained by the component of a concurrent variable‐interval 60‐s variable‐interval 60‐s schedule associated with a higher reinforcement magnitude. In Experiment 4, higher rates of response were produced in the component of a multiple variable‐interval 60‐s variable‐interval 60‐s schedule associated with the higher reinforcement magnitude. It is suggested that on simple schedules greater reinforcer magnitudes shape the reinforced pattern of responding more effectively than do smaller reinforcement magnitudes. This effect is, however, overridden by another process, such a contrast, when two magnitudes are presented within a single session on two‐component schedules.
CONDITIONED REINFORCEMENT VALUE AND CHOICE
Authors: Preston Ray A. , Fantino Edmund
Published: March 2006

The delay‐reduction hypothesis of conditioned reinforcement states that the reinforcing value of a food‐associated stimulus is determined by the delay to primary reinforcement signaled by the onset of the stimulus relative to the average delay to primary reinforcement in the conditioning situation. In contrast, most contemporary models of conditioned reinforcement strength posit that the reinforcing strength of a stimulus is some simple function only of the delay to primary reinforcement in the presence of stimulus. The delay‐reduction hypothesis diverges from other conditioned reinforcement models in that it predicts that a fixed‐duration food‐paired stimulus will have different reinforcing values depending on the frequency of its presentation. In Experiment 1, pigeons' key pecks were reinforced according to concurrent‐chains schedules with variable‐interval 10‐second and variable‐interval 20‐second terminal‐link schedules. The initial‐link schedule preceding the shorter terminal link was always variable‐interval 60 seconds, and the initial‐link schedule requirement preceding the longer terminal link was varied between 1 second and 60 seconds across conditions. In Experiment 2, the initial‐link schedule preceding the longer of two terminal links was varied for each of three groups of pigeons. The terminal links of the concurrent chains for the three groups were variable‐interval 10 seconds and 20 seconds, variable‐interval 10 seconds and 30 seconds, and variable‐interval 30 seconds and 50 seconds. In both experiments, preference for the shorter terminal link was either a bitonic function or an inverse function of the initial‐link schedule preceding the longer terminal‐link schedule. Consistent with the predictions of the delay‐reduction hypothesis, the relative values of the terminal‐link stimuli changed as a function of the overall frequency of primary reinforcement. Vaughan's (1985) melioration model, which was shown to be formally similar to Squires and Fantino's (1971) delay‐reduction model, can be modified so as to predict these results without changing its underlying assumptions.
CONCURRENT SCHEDULES: EFFECTS OF TIME‐ AND RESPONSE‐ALLOCATION CONSTRAINTS
Authors: Davison Michael
Published: March 2006

Five pigeons were trained on concurrent variable‐interval schedules arranged on two keys. In Part 1 of the experiment, the subjects responded under no constraints, and the ratios of reinforcers obtainable were varied over five levels. In Part 2, the conditions of the experiment were changed such that the time spent responding on the left key before a subsequent changeover to the right key determined the minimum time that must be spent responding on the right key before a changeover to the left key could occur. When the left key provided a higher reinforcer rate than the right key, this procedure ensured that the time allocated to the two keys was approximately equal. The data showed that such a time‐allocation constraint only marginally constrained response allocation. In Part 3, the numbers of responses emitted on the left key before a changeover to the right key determined the minimum number of responses that had to be emitted on the right key before a changeover to the left key could occur. This response constraint completely constrained time allocation. These data are consistent with the view that response allocation is a fundamental process (and time allocation a derivative process), or that response and time allocation are independently controlled, in concurrent‐schedule performance.
CHOICE BY RATS FOR ENRICHED VERSUS STANDARD HOME CAGES: PLASTIC PIPES, WOOD PLATFORMS, WOOD CHIPS, AND PAPER TOWELS AS ENRICHMENT ITEMS
Authors: Bradshaw A. Lynn , Poling Alan
Published: March 2006

The purpose of the present study was to determine whether simple additions to the home cages of rats made those cages preferable to standard housing arrangements. Results indicated that most rats preferred cages with wood platforms, wood chips, and paper towels to otherwise identical cages without these items. Wood chips were not, however, practical with the cages used in the present study. Plastic pipes caused no problems but were not preferred by most animals. Both wood platforms and paper towels created no problems and appeared to be useful as enrichment items. The latter were preferred to the former in a direct comparison.
STIMULUS CONTROL OF PAVLOVIAN FACILITATION
Authors: Parker B. Kent , Serdikoff Sherry L. , Kaminski Barbara J. , Critchfield Thomas S.
Published: March 2006

Two experiments were conducted using an autoshaping procedure with pigeons to examine whether dimensional stimulus control by a Pavlovian facilitator parallels the control established following operant discrimination training. Facilitation training consisted of the presentation of a black vertical line on a white background as the B stimulus in a feature‐positive discrimination in which the A stimulus (white keylight) was followed by grain presentation only if preceded by B. In this way, B facilitates or sets the occasion for pecking at A. Subsequent testing for generalization along the line‐orientation dimension produced decremental gradients when the facilitation paradigm incorporated an explicit feature‐negative stimulus (B‐). These results parallel the decremental control obtained following operant discrimination training and suggest that Pavlovian facilitators and instrumental discriminative stimuli are functionally equivalent.
PREFERENCE FOR CONDITIONED REINFORCEMENT
Authors: Williams Ben A. , Dunn Roger
Published: March 2006

Pigeons were presented with a concurrent‐chains schedule in which both choice alternatives led to the same terminal‐link stimulus, which was followed by food. Superimposed on the food‐reinforced presentations of the terminal‐link stimulus was a second schedule of presentations of the same stimulus that were followed by no food. The absolute number of these no‐food stimulus presentations was held constant while their relative frequency assigned to one or the other choice alternative was systematically varied. Preference for a given choice alternative tracked the relative frequency of these stimulus presentations, thus demonstrating that they served as reinforcers. These results resolve conflicts in the literature regarding the effect of conditioned reinforcement on choice.
CHOICE WITH PROBABILISTIC REINFORCEMENT: EFFECTS OF DELAY AND CONDITIONED REINFORCERS
Authors: Mazur James E.
Published: March 2006

Two experiments measured pigeons' choices between probabilistic reinforcers and certain but delayed reinforcers. In Experiment 1, a peck on a red key led to a 5‐s delay and then a possible reinforcer (with a probability of .2). A peck on a green key led to a certain reinforcer after an adjusting delay. This delay was adjusted over trials so as to estimate an indifference point, or a duration at which the two alternatives were chosen about equally often. In all conditions, red houselights were present during the 5‐s delay on reinforced trials with the probabilistic alternative, but the houselight colors on nonreinforced trials differed across conditions. Subjects showed a stronger preference for the probabilistic alternative when the houselights were a different color (white or blue) during the delay on nonreinforced trials than when they were red on both reinforced and nonreinforced trials. These results supported the hypothesis that the value or effectiveness of a probabilistic reinforcer is inversely related to the cumulative time per reinforcer spent in the presence of stimuli associated with the probabilistic alternative. Experiment 2 tested some quantitative versions of this hypothesis by varying the delay for the probabilistic alternative (either 0 s or 2 s) and the probability of reinforcement (from .1 to 1.0). The results were best described by an equation that took into account both the cumulative durations of stimuli associated with the probabilistic reinforcer and the variability in these durations from one reinforcer to the next.
DEVELOPMENT AND CROSSMODAL TRANSFER OF CONTEXTUAL CONTROL OF EMERGENT STIMULUS RELATIONS
Authors: Lynch Deirdre C. , Green Gina
Published: March 2006

Six normally capable adults first learned three conditional relations in each of two prospective equivalence classes via match‐to‐sample training with figures as conditional (sample) and discriminative (comparison) stimuli. Then one trained conditional relation in each prospective class was brought under the control of contextual stimuli, two dictated nonsense syllables. Test performances indicated the emergence of untrained conditional relations, and therefore two equivalence classes, that were conditional on the contextual stimuli. These tests involved untrained combinations of contextual stimuli and stimuli in conditional relations, suggesting that the contextual stimuli functioned independently to control conditional relations rather than forming compound stimuli with samples and comparisons in training. Next, two novel figures were made equivalent to each of the original dictated contextual stimuli by match‐to‐sample training and testing. On subsequent tests, all subjects demonstrated transfer of conditional control of untrained conditional relations from the original auditory contextual stimuli to equivalent visual stimuli. These outcomes further supported the conclusion that the contextual stimuli exerted true conditional control over conditional relations in the equivalence classes and were not merely elements of compound stimuli.
A QUANTITATIVE INTERRESPONSE‐TIME ANALYSIS OF DRL PERFORMANCE DIFFERENTIATES SIMILAR EFFECTS OF THE ANTIDEPRESSANT DESIPRAMINE AND THE NOVEL ANXIOLYTIC GEPIRONE
Authors: Richards Jerry B. , Seiden Lewis S.
Published: March 2006

We describe an interresponse‐time analysis of performance on a differential‐reinforcement‐of‐low‐rate 72‐s schedule. This analysis compares the obtained interresponse‐time distribution of individual rats to a corresponding random interresponse‐time distribution. The random interresponse‐time distribution is a negative exponential probability function; it predicts the relative distribution of interresponse times if the rat emitted the same number of responses randomly (i.e., with a constant probability) with respect to time. The analysis provides quantitative measures of peak location and dispersion of the interresponse times toward random performance. In Experiment 1, an unexpected outcome of this analysis was that the rats would have obtained more reinforcers had they responded at the same rate but randomly. Based on the interresponse‐time analysis in Experiment 1, it was shown that rats trained on the differential‐reinforcement‐of‐low‐rate 72‐s schedule could increase the number of reinforcers obtained in two ways: first, by a coherent shift of the interresponse‐time distribution toward longer durations and, second, by dispersal of the interresponse times toward a random interresponse‐time distribution. Experiment 2 applied the analysis described in Experiment 1 to the effects of desipramine and gepirone. Both drugs decreased response rate and increased reinforcement rate, but their effects on the distribution of interresponse times were different. The increase in reinforcement rate observed with desipramine was accompanied by a coherent shift of the peak of the interresponse‐time distribution to the right. The increase in reinforcement rate observed with gepirone was accompanied by dispersal of the interresponse‐time distribution toward the random negative exponential prediction.
DISTINGUISHING BETWEEN HALOPERIDOL'S AND DECAMETHONIUM'S DISRUPTIVE EFFECTS ON OPERANT BEHAVIOR IN RATS: USE OF MEASUREMENTS THAT COMPLEMENT RESPONSE RATE
Authors: Fowler Stephen C. , Skjoldager Paul D. , Liao Ruey‐Ming , Chase J. Michael , Johnson Julie S.
Published: March 2006

The behavioral effects of haloperidol (0.04 to 0.16 mg/kg) and nonparalytic doses of decamethonium (0.2 to 0.8 mg/kg) were studied with operant methods that permitted the measurement of response rate, peak force of response, duration of response, and duration of the rat's head entry into the reinforcement dipper well. Type of operant response topography (forelimb press or forelimb grasp‐and‐pull) and peak force (low or high) required for reinforcement delivery were independent variables. The low‐force, press‐topography condition yielded qualitatively different profiles for the two drugs. Haloperidol increased peak force and duration of operant response, increased maximum head entry duration, and temporally dissociated forelimb and head entry behavior. Decamethonium decreased force and duration of operant response, did not appreciably affect maximum head entry duration, and did not influence the normal temporal coupling of forelimb and head entry responses. The haloperidol effects were seen as reflections of pseudo‐Parkinsonism, not muscle weakness, which appeared to be the primary source of decamethonium's behavioral effects.
FOOD‐PAIRED STIMULI AS CONDITIONED REINFORCERS: EFFECTS OF d‐AMPHETAMINE
Authors: Cohen Steven L. , Branch Marc N.
Published: March 2006

Seven pigeons were studied in two experiments in which key pecks were reinforced under a second‐order schedule wherein satisfaction of variable‐interval schedule requirements produced food or a brief stimulus. In the second part of each session, responses produced only the brief stimulus according to a variable‐interval schedule (food extinction). For the 4 pigeons in Experiment 1, the response key was red throughout the session. In separate phases, the brief stimulus was either paired with food, not paired with food, or not presented during extinction. d‐Amphetamine (0.3 to 10.0 mg/kg) dose‐dependently reduced food‐maintained responding during the first part of the session and, at intermediate dosages, increased responding during the extinction portion of the session. The magnitude of these increases, however, did not consistently depend on whether the brief stimulus was paired, not paired, or not presented. It was also true that under nondrug conditions, response rates during extinction did not differ reliably depending on pairing operations for the brief stimulus. In Experiment 2, 3 different pigeons responded under a procedure wherein the key was red in the component with food presentations and blue in the extinction component (i.e., multiple schedule). Again, d‐amphetamine produced dose‐related decreases in responding during the first part of a session and increases in responding in the second part of the session. These increases, however, were related to the pairing operations; larger increases were observed when the brief stimulus was paired with food than when it was not or when it was not presented at all. Under nondrug conditions, the paired brief stimulus controlled higher response rates during extinction than did a nonpaired stimulus or no stimulus. These findings suggest that d‐amphetamine can enhance the efficacy of conditioned reinforcers, and that this effect may be more robust if conditioned reinforcers occur in the context of a signaled period of extinction.
EFFECTS OF d‐AMPHETAMINE ON RESPONDING UNDER SECOND‐ORDER SCHEDULES OF REINFORCEMENT WITH PAIRED AND NONPAIRED BRIEF STIMULI
Authors: Cohen Steven L.
Published: March 2006

Three pigeons were studied under a multiple schedule in which pecks in each component were reinforced according to a variable‐interval 120‐s second‐order schedule with fixed‐interval 60‐s units. In the first component of the multiple schedule, the completion of a fixed interval produced either food or a 4‐s change in key color plus houselight illumination. In the second component an identical schedule was in effect, but the stimulus was a 0.3‐s change in key color. Both long and short brief stimuli were not paired with food presentations in Conditions 1 and 3 and were paired with food in Condition 2. There were no consistent differences in response patterns under paired and nonpaired brief‐stimulus conditions when the stimulus was a 4‐s change in key color accompanied by houselight illumination. However, pairing the 0.3‐s key‐color change with food presentations resulted in higher indices of curvature and lower response rates in the early segments of the fixed interval than when the stimulus was not paired with food presentations. Low doses of d‐amphetamine (0.3 and 1 mg/kg) produced small and inconsistent increases in overall response rates, and higher doses (3 and 10 mg/kg) decreased overall response rates. d‐Amphetamine altered response patterns within fixed intervals by decreasing the indices of curvature and increasing response rates in the early segments of the fixed interval. Response rates and patterns under paired and nonpaired brief‐stimulus conditions were not differentially affected by d‐amphetamine. Thus, evidence for the enhancement of the conditioned reinforcement effects of psychomotor stimulant drugs was not found with the second‐order schedules used in the present study.
DRUG DISCRIMINATION USING A CONDITIONED TASTE‐AVERSION PARADIGM IN RHESUS MONKEYS
Authors: Glowa John R. , Jeffreys Ronald D. , Riley Anthony L.
Published: March 2006

The development of drug discrimination was assessed in rhesus monkeys using the conditioned taste‐aversion paradigm. Monkeys were initially trained to respond under a fixed‐ratio 30‐response schedule of food‐pellet delivery to assess the rate‐decreasing effects of alprazolam (0.03 to 3 mg/kg, i.m., 60 min presession). Alprazolam decreased responding at doses greater than 0.1 mg/kg. Discriminative stimulus effects of alprazolam were then assessed by giving 0.03 mg/kg before sessions in which 1.8 mEq/kg lithium chloride was given immediately after the session (alprazolam/lithium session). On intervening days, saline was given before and after the session (saline/saline session). Rates of responding decreased over successive alprazolam/lithium sessions and also during the saline/saline session that immediately followed an alprazolam/lithium session. During subsequent saline/saline sessions, rates of responding returned to levels near baseline rates within two to four sessions. The discriminative stimulus effects of alprazolam were then assessed by giving 0.1 mg/kg before sessions in which 1 mg/kg d‐amphetamine was given immediately after the session (alprazolam/d‐amphetamine session). Rates of responding decreased during subsequent alprazolam/d‐amphetamine sessions in drug‐experienced monkeys, but did not decrease during intervening saline/saline sessions. These findings demonstrate that drug stimuli associated with postsession drug injections can rapidly develop control over behavior and suggest that similar methods be explored in the assessment of drug discrimination.
MODIFYING DRUG‐REINFORCED BEHAVIOR BY ALTERING THE ECONOMIC CONDITIONS OF THE DRUG AND A NONDRUG REINFORCER
Authors: Carroll Marilyn E. , Carmona Gilberto G. , May Susan A.
Published: March 2006

Six rhesus monkeys were trained to self‐administer orally delivered phencyclidine (0.25 mg/mL) and saccharin (0.03% wt/vol) under concurrent fixed‐ratio 16 schedules. In Condition 1 the fixed‐ratio requirement for phencyclidine was changed from 16 to 4, 8, 16, 32, 64, 128 and 16 while the fixed‐ratio requirement for saccharin deliveries remained constant at 16. In Condition 2 the fixed‐ratio value for saccharin was systematically altered while the fixed‐ratio requirement for phencyclidine remained at 16, and in Condition 3 the fixed‐ratio requirements for both phencyclidine and saccharin were altered simultaneously. Water was then substituted for saccharin, and the series of fixed‐ratio manipulations was replicated. The phencyclidine concentration was reduced to 0.125 mg/mL and Conditions 1 and 3 were repeated. When the fixed‐ratio requirement for phencyclidine was increased and the fixed‐ratio requirement for saccharin or water remained fixed at 16, phencyclidine deliveries decreased when saccharin (vs. water) was concurrently available. The magnitude of the decrease ranged from 20% to 90% (of the concurrent water condition) as the fixed‐ratio requirement for phencyclidine increased from 4 to 128. When the fixed‐ratio requirement for phencyclidine remained at 16 and the fixed‐ratio requirements for concurrent saccharin or water varied between 4 and 128, phencyclidine deliveries decreased by 30% to 40% due to the concurrent availability of saccharin (vs. water). This decrease occurred only at the three lowest fixed‐ratio values when saccharin intake was relatively high. When the fixed‐ratio requirements for both phencyclidine and concurrent saccharin or water were varied simultaneously, phencyclidine deliveries were reduced from 20% to 45% when saccharin (vs. water) was concurrently present. There was little effect of reducing the phencyclidine concentration when the data were analyzed in terms of unit price (responses per milligram). Thus, changes in the fixed‐ratio requirement or drug concentration were functionally similar, and unit price of phencyclidine was the variable that was influenced by the presence of concurrent saccharin. These data indicate that drug‐reinforced behavior is substantially reduced when the environment is enriched with an alternative nondrug reinforcer. The economic context in which these substances are presented is an important determinant of drug‐reinforced behavior.
BEHAVIORAL ECONOMICS OF DRUG SELF‐ADMINISTRATION AND DRUG ABUSE POLICY
Authors: Hursh Steven R.
Published: March 2006

The concepts of behavioral economics have proven useful for understanding the environmental control of overall levels of responding for a variety of commodities, including reinforcement by drug self‐administration. These general concepts are summarized for application to the analysis of drug‐reinforced behavior and proposed as the basis for future applications. This behavioral agenda includes the assessment of abuse liability, the assay of drug‐reinforcer interactions, the design of drug abuse interventions, and the formulation of drug abuse public policy. These separate domains of investigation are described as part of an overall strategy for designing model projects to control drug use and testing public policy initiatives.
AN ECONOMIC ANALYSIS OF “DEMAND” FOR FOOD IN BABOONS
Authors: Foltin Richard W.
Published: March 2006

Responding of 6 adult male baboons (Papio c. anubis) was maintained under a fixed‐ratio schedule of food reinforcement during daily 22‐hr experimental sessions. Completion of the ratio requirement resulted in the delivery of a single 1‐g food pellet; supplemental feeding was limited to a daily fruit ration. Ratio values were increased on Mondays, Wednesdays, and Fridays according to the following schedule: 2, 4, 8, 16, 32, 64, 96, 128. Responding under each ratio value was examined four times. Under the Fixed‐Ratio 2 conditions, food intake ranged between 300 and 600 g. Ratios were increased for each baboon until food intake decreased to about 100 g (20% to 30% of Fixed‐Ratio 2 intake). Increasing the response cost increased total time responding and total daily responding in all baboons, but this increase in responding was not sufficient to maintain stable food intake. Baboons responded between 90 and 180 min per day. The highest running response rates were observed under the Fixed‐Ratio 2 and Fixed‐Ratio 4 schedules. Running rate was similar across the larger ratio values (greater than Fixed‐Ratio 8) but was lower than that observed under the Fixed‐Ratio 2 and Fixed‐Ratio 4 schedules. Similar results were observed the four times that each fixed‐ratio value was tested. Intake as a function of cost was analyzed by fitting data to the nonlinear equation proposed by Hursh, Raslear, Shurtleff, Bauman, and Simmons (1988) for “demand” functions. Demand for food was inelastic over most of the ratio values until food intake decreased to 15% to 55% of baseline. The results indicate that demand functions are appropriate for the study of food intake in baboons, but also caution that intake at the cost when demand shifts from inelastic to elastic and its relationship to maximal intake should also be included in analyses of demand for a commodity.
STIMULUS EQUIVALENCE AND ARBITRARILY APPLICABLE RELATIONAL RESPONDING
Authors: Steele David , Hayes Steven C.
Published: March 2006

Subjects' responses to nonarbitrary stimulus relations of sameness, oppositeness, or difference were brought under contextual control. In the presence of the SAME context, selecting the same comparison as the sample was reinforced. In the presence of the OPPOSITE context, selecting a comparison as far from the sample as possible on the physical dimension defined by the set of comparisons was reinforced. Given the DIFFERENT context, selecting any comparison other than the sample was reinforced. Subjects were then exposed to arbitrary matching‐to‐sample training in the presence of these same contextual cues. Some subjects received training using the SAME and OPPOSITE contexts, others received SAME and DIFFERENT, and others received SAME, OPPOSITE, and DIFFERENT. The stimulus networks established allowed testing for a wide variety of derived relations. In two experiments it was shown that derived performances were consistent with relational responding brought to bear by the contextual cues. In contexts relevant to the relation of sameness, stimulus equivalence emerged. Other kinds of relational networks emerged in the other contexts. Arbitrarily applicable relational responding may give rise to a very wide variety of derived stimulus relations. The kinds of performances seen in stimulus equivalence do not appear to be unique.
RESPONSE PATTERNS AND CARDIOVASCULAR EFFECTS DURING RESPONSE SEQUENCE ACQUISITION BY HUMANS
Authors: Kelly Thomas H. , Fischman Marian W. , Foltin Richard W. , Brady Joseph V.
Published: March 2006

The effects of temporal delays imposed between successive responses and of vitamin C administration were examined on the acquisition of response sequences and on cardiovascular reactivity during sequence acquisition. Thirteen adult subjects (6 female, 7 male), in good health, gave written consent prior to participating in 12 weekly 45‐min sessions. Points, exchanged for money after each session, were presented when subjects completed 15‐response sequences on a touch‐sensitive three‐response keypad. A position counter increased from 0 to 14 as subjects emitted correct responses in the sequence. Four novel 15‐response sequences were presented each session. No delays were imposed between successive responses during the acquisition of one sequence; delays were imposed immediately following each response during the acquisition of a second sequence, thereby delaying response feedback; delays were imposed following feedback during acquisition of a third sequence, resulting in the removal of the stimulus correlated with sequence position; and, as a control condition, delays were imposed following feedback, but stimuli correlated with sequence position were reinstated prior to the next response during acquisition of a fourth sequence. Subjects were exposed to one of two delay durations (0.2 and 0.5 or 0.5 and 1.0 s) each session, and delay durations alternated every session. During Weeks 5 to 8, subjects received 3 grams of vitamin C per day, whereas during Weeks 1 to 4 and 9 to 12, subjects received placebo under single‐blind conditions. All subjects acquired the sequences, as evidenced by decreasing percentages of incorrect responses across trials. When temporal delays were imposed between successive responses during sequence acquisition, acquisition efficiency was enhanced. Examination of response latencies suggested that the status of preceding responses (i.e., correct or incorrect) rather than the status of the position counter influenced subsequent responding. Cardiovascular effects were inversely related to the length of the temporal delay. Neither cardiovascular reactivity or sequence acquisition were related to vitamin C administration.
GENERALIZATION PEAK SHIFT FOR AUTOSHAPED AND OPERANT KEY PECKS
Authors: Weiss Stanley J. , Weissman Richard D.
Published: March 2006

Pigeons acquired discriminated key pecking between 528‐ and 540‐nm stimuli by either a response—reinforcer (operant group) or a stimulus—reinforcer (autoshaped group) contingency, with other training‐schedule parameters comparable over groups. For the birds in the operant group, key pecks intermittently produced grain in the presence of one hue on the key (positive stimulus) but not in the other (negative stimulus). For the birds in the autoshaped group, pecking emerged when grain was intermittently presented independently of key pecking during one key color but was not presented during the other key color. Two independent contingency assays, peck‐location comparisons and elimination of differences in reinforcement rate, confirmed the effectiveness of the two training procedures in establishing operant or respondent control of key pecking. After reaching a 10:1, or better, discrimination ratio between key pecks during the two key colors, the birds received a wavelength generalization test. Criterion baseline key‐peck rates were comparable for operant and autoshaped groups prior to testing. On the generalization test, performed in extinction, all birds pecked most at a stimulus removed from the positive training stimulus in the direction away from the negative stimulus. In testing, autoshaped “peak” rates (24.5 to 64.9 pecks per minute) were from 33% to 80% higher than rates in the presence of the training stimuli. Respondent peak shift rarely has been reported heretofore, and never this consistently and robustly. These results further confirm the similarity of perceptual processing in classical and operant learning. They are discussed in terms of Spence's gradient‐interaction theory and Weiss' (1978) two‐process model of stimulus control.
TIME‐PLACE LEARNING BY PIGEONS, COLUMBA LIVIA
Authors: Wilkie Donald M. , Willson Robert J.
Published: March 2006

In each of two experiments, 2 pigeons received discrimination training in which food reinforcement for key pecking was conditional upon both spatial and temporal cues. In Experiment 1, food was available for periods of 30 s at each of three locations (pecking keys) during trials that lasted 90 s. In Experiment 2, food was available for periods of 15 min at each of four locations (pecking keys) during a 60‐min trial. In both experiments, pigeons' key pecking was jointly controlled by the spatial and temporal cues. These data, and other recent experiments, suggest that animals learn relationships between temporal and spatial cues that predict stable patterns of food availability.
BEHAVIORAL CONTRAST: PAVLOVIAN EFFECTS AND ANTICIPATORY CONTRAST
Authors: Hassin‐Herman Alison D. , Hemmes Nancy S. , Brown Bruce L.
Published: March 2006

Two sources of behavioral contrast have been identified previously: Pavlovian stimulus‐reinforcer relations and component sequence effects (anticipatory contrast). This study sought to isolate these sources of control procedurally in a four‐ply multiple schedule composed of two fixed two‐component sequences. Different cues were associated with the first component of each sequence, and contrast effects were studied in these target components. In Experiment 1, differential cuing of Component 2 between sequences and availability of reinforcement during target components were varied across three groups of pigeons; the stimulus‐reinforcer relation between target‐component cues and schedule of reinforcement in Component 2 was varied within subjects. Control by the Pavlovian relation was demonstrated under all conditions, and anticipatory contrast was not observed. In Experiment 2, target‐component duration was systematically varied in the three groups of Experiment 1. Control by the Pavlovian relation was reliably obtained only when target‐component behavior was unreinforced, and diminished with increases in component duration. Anticipatory contrast emerged in the two groups for which target‐component reinforcement was available. These and other data indicate that Pavlovian effects in multiple schedules may be obscured when the requisite conditions for anticipatory contrast are present.
APPLICATION OF HERRNSTEIN'S HYPERBOLA TO TIME ALLOCATION OF NATURALISTIC HUMAN BEHAVIOR MAINTAINED BY NATURALISTIC SOCIAL REINFORCEMENT
Authors: Beardsley Scott D. , McDowell J. J
Published: March 2006

Five college students talked to an experimenter about various topics. Time spent looking at the experimenter was reinforced by verbal statements of praise and interest on five variable‐interval schedules. Herrnstein's hyperbola provided a good description of the time‐allocation data for 4 of the 5 subjects, and accounted for 95% of the variance of the median time‐allocation data. The hyperbola provided a significantly better description of the data than a two‐parameter ramp function with similar differential properties. Estimates of the asymptote, k, of the hyperbola varied among subjects from about 2 to about 15 seconds of eye contact per minute. These estimates were much smaller than the constant 60 seconds of eye contact per minute required by Herrnstein's matching theory. These results support the conclusion that Herrnstein's hyperbola describes naturalistic human behavior maintained by naturalistic social reinforcement as well as it describes the behavior of humans and nonhumans in typical laboratory preparations. The results also indicate that the hyperbolic form of the time‐allocation version of Herrnstein's equation is accurate, but that the constant k requirement of matching theory may not hold.
FIXED‐INTERVAL PERFORMANCE AND SELF‐CONTROL IN CHILDREN
Authors: Darcheville J. C. , Rivière V. , Wearden J. H.
Published: March 2006

Operant responses of 16 children (mean age 6 years and 1 month) were reinforced according to different fixed‐interval schedules (with interreinforcer intervals of 20, 30, or 40 s) in which the reinforcers were either 20‐s or 40‐s presentations of a cartoon. In another procedure, they received training on a self‐control paradigm in which both reinforcer delay (0.5 s or 40 s) and reinforcer duration (20 s or 40 s of cartoons) varied, and subjects were offered a choice between various combinations of delay and duration. Individual differences in behavior under the self‐control procedure were precisely mirrored by individual differences under the fixed‐interval schedule. Children who chose the smaller immediate reinforcer on the self‐control procedure (impulsive) produced short postreinforcement pauses and high response rates in the fixed‐interval conditions, and both measures changed little with changes in fixed‐interval value. Conversely, children who chose the larger delayed reinforcer in the self‐control condition (the self‐controlled subjects) exhibited lower response rates and long postreinforcement pauses, which changed systematically with changes in the interval, in their fixed‐interval performances.
REAL‐TIME DETECTION OF ORIENTATION DURING NEGATIVE BEHAVIORAL CONTRAST WITH KEY PECKING AND A TURNING RESPONSE
Authors: Manabe Kazuchika
Published: March 2006

We developed a video system for real‐time detection of a pigeon's orientation and for reinforcement of a “turning response.” Using this system, negative behavioral contrast was found across key‐peck and turning responses. In addition, turning away from the pecking key was detected by the system just after presentation of the negative discriminative stimulus on the key. The results suggest that avoidance of the discriminative stimulus in the constant component, which has been regarded as a causal factor for negative contrast (additivity theory), is not the primary factor for negative behavioral contrast of pigeons' key pecking, but may account for negative local contrast.
AN INTEGRATIVE MODEL FOR THE STUDY OF BEHAVIORAL MOMENTUM
Authors: Nevin John A.
Published: March 2006

Behavioral momentum is the product of response rate and resistance to change. The data on relative resistance to change are summarized for pigeons responding on single‐key two‐component multiple schedules, in the initial links of two‐key multiple chained schedules, and in equivalent components of two‐key serial schedules. For single‐key procedures, the ratio of resistance to change in two schedule components is shown to depend on the ratio of reinforcer rates obtained in the presence of the component stimuli. For two‐key procedures, the ratio of resistance to change in equivalent components is shown to depend on the ratio of reinforcer rates correlated with key locations. A model based on stimulus‐reinforcer contingencies that combines the reinforcer rates in schedule components summed over key locations and reinforcer rates correlated with key locations summed over components, each expressed relative to the session average reinforcer rate, gives a good account of the data. An extension of the relative law of effect for multiple schedules fails to provide a complete account of resistance to change, but both approaches are needed for a comprehensive understanding of behavioral momentum.