bluuebunny/crossref_metadata_2025 huggingface dataset:
CODING RESPONSES AND THE GENERALIZATION OF MATCHING TO SAMPLE IN CHILDREN
Authors: Lowenkron Barry
Published: March 2006

Two experiments studied the conditions of stimulus control necessary for the generalization of relational matching to sample. Matching required the selection of comparison shapes rotated 90° clockwise from the orientation of the corresponding sample. In Experiment 1, five children were taught to: (a) code the orientations of samples, (b) transform sample codings to account for the 90° rotation, and (c) repeat the transformed sample coding response to a comparison. High levels of generalization occurred with a set of novel stimuli for which stable sample‐coding responses were initially available. In another novel set, where stable sample‐coding responses were not initially available, low levels of generalized matching were recorded. Matching performance improved after stable coding responses were trained. In Experiment 2, two children and three adults were trained in a form of the matching task that produced poor generalization despite the presence of stable sample‐coding responses. Retraining to modify the stimulus control exerted by these coding responses produced an immediate improvement in generalized matching to sample. Results suggest that the generalization of matching is dependent on the structure of stimulus control that the component responses exert on each other.
MELIORATION AND MAXIMIZATION OF REINFORCEMENT MINUS COSTS OF BEHAVIOR
Authors: Boelens Harrie
Published: March 2006

Eight pigeons were exposed to independent concurrent schedules. Concurrent variable‐interval 60‐second variable‐interval 60‐second schedules were presented to one group of four subjects. Following baseline training, a limited hold was added to one of the schedules and the duration of the hold was decreased in successive conditions. Concurrent variable‐interval 120‐second variable‐interval 40‐second schedules were presented to another group of four subjects. These subjects were first exposed to decreasing durations of a limited hold in the variable‐interval 40‐second component. After replication of the baseline, a limited hold in the variable‐interval 120‐second component was decreased in duration. The initial durations of the holds were determined from the subjects' responding in the baseline conditions. A duration was chosen such that approximately 25% of the scheduled reinforcers would be canceled if responding remained unchanged.

Approximate matching of time proportions and reinforcement proportions was observed when the limited hold was added to the variable‐interval 60‐second schedule and when the limited hold was added to the variable‐interval 40‐second schedule. Time proportions were less extreme than reinforcement proportions when the limited hold operated in a variable‐interval 120‐second schedule. Overall reinforcement rates tended to decrease with continued training in concurrent schedules with a limited hold. Absolute deviations from time matching also decreased. The results provide evidence against the principle of reinforcement maximization, and support Herrnstein and Vaughan's (1980) melioration hypothesis.
PREFERENCE IN PIGEONS GIVEN A CHOICE BETWEEN SEQUENCES OF FIXED‐RATIO SCHEDULES: EFFECTS OF RATIO VALUES AND DURATION OF FOOD DELIVERY
Authors: Hall‐Johnson Earl , Poling Alan
Published: March 2006

Pigeons were exposed to schedules that consisted of two sequential fixed ratios, the completion of each followed by food delivery. When each alternative provided two food deliveries per 100 responses, the schedule with the shorter initial fixed‐ratio value was consistendy preferred. Subsequent attempts were made to shift this established preference by (1) increasing the ratio requirement in the second fixed ratio of the preferred schedule; (2) increasing the duration of food delivery in the second fixed ratio of the nonpreferred schedule; (3) decreasing the duration of food delivery in the first fixed ratio of the preferred schedule; and (4) shortening the second fixed ratio of the nonpreferred schedule. Preference shifted from the schedule with the shorter initial fixed ratio only when the duration of food delivery associated with the first fixed ratio of that schedule was too brief to allow eating. Under all other conditions, pigeons strongly preferred the schedule with the shorter initial fixed ratio even when, overall, that schedule yielded briefer access to food or required more responses to obtain equivalent access.
THE DOUBLE‐ALTERNATIVE, DOUBLE‐START EXPERIMENTAL APPARATUS: A NEW PROCEDURE FOR MEASURING PREFERENCE
Authors: Biederman G. B. , Furedy J. J. , Heighington G. A.
Published: March 2006

A new experimental chamber is described that permits rats to demonstrate behavioral preference for one of two conditions by running towards a goal chamber by one of two routes that are correlated with the different conditions. In a preliminary study, rats chose a route correlated with relatively lower shock, demonstrating the sensitivity of the apparatus. We also report evidence using this device that, of 10 rats tested, all preferred unsignaled rather than signaled, inescapable, unavoidable shock.
STIMULUS EQUIVALENCE AND TRANSITIVE ASSOCIATIONS: A METHODOLOGICAL ANALYSIS
Authors: Fields Lanny , Verhave Thom , Fath Stephen
Published: March 2006

When a number of two‐stimulus relations are established through training within a set of stimuli, other two‐stimulus relations often emerge in the same set without direct training. These, termed “transitive stimulus relations,” have been demonstrated with a variety of visual and auditory stimuli. The phenomenon has served as a behavioral model for explaining the emergence of rudimentary comprehension and reading skills, and the development of generative syntactic repertoires. This article considers the range of relations that can arise between a given number of stimuli in a class, the number of directly established two‐stimulus relations necessary for the emergence of transitive relations, the forms that training sets of stimuli can take, and the number of transitive two‐stimulus relations that can be induced without direct training. The procedures needed to establish and assess transitive stimulus control, the possible interactions between the training and testing procedures, and the constraints these interactions place upon the analysis of transitive stimulus control are also examined. The present analysis indicates that in a transitivity test, choice among such stimuli may be controlled by (1) the relation between the sample and the positive comparison stimulus (transitive stimulus control), (2) the relation between the sample and the negative comparison stimulus (S‐ rule control), and (3) possible discriminative properties that may inadvertently be established in the positive and negative comparison stimuli (valence control). Methods are described for distinguishing these three forms of stimulus control.
OPERANT CONDITIONING OF AUTOGROOMING IN VERVET MONKEYS (Cercopithecus aethiops)
Authors: Iversen Iver H. , Ragnarsdottir G. Adda , Randrup Kirsten I.
Published: March 2006

Vervet monkeys received food reinforcement contingent on autogrooming. Experiment 1 reinforced grooming on a schedule of increasing intermittency and grooming increased in frequency and duration; with only pauses reinforced, grooming decreased in frequency and duration. Experiment 2 demonstrated differentiation of operant autogrooming; in each session a different single form of grooming was reinforced (for example, grooming the tail only), and that form increased in frequency while other forms became less frequent. In Experiment 3 scratching was succesfully conditioned with a method that selectively reinforced variety in behavior; reinforcement was contingent on a shift in scratching form. In Experiment 4, with no contingencies on grooming, a prefood stimulus did not increase autogrooming whether or not grooming had previously resulted in contingent reinforcement. The form of conditioned autogrooming resembled the form of unconditioned autogrooming. The discussion suggests how reinforcement principles can account for changes in the topography of operant behavior.
TRANSFER OF MATCHING‐TO‐FIGURE SAMPLES IN THE PIGEON
Authors: Pisagreta Richard , Redwood Edward , Witt Kevin
Published: March 2006

Three pigeons were trained on a modified six‐key matching‐to‐sample procedure. The third peck on the figure‐sample key (which presented a bird, hand, face, beetle, rabbit, fish, flower, or red hue, as the sample) lighted only one comparison key. Every three additional pecks on the sample lighted another comparison key, up to a maximum of five keys. Pecks on keys of matching figures produced grain. Pecks on nonmatching keys (mismatches) turned off all lights on the comparison keys and repeated the trial. Three figures were used during acquisition. The birds learned to peck each sample until the matching comparison stimulus appeared on one of three comparison stimulus keys, and then to peck that key. Later, five novel stimuli, employed as both sample and comparison stimuli, and two additional matching keys were added. Each bird showed matching transfer to the novel samples. The data suggest that the birds may have learned the concept of figure matching rather than a series of two‐component chains or discrete five‐key discriminations.
INTERREINFORCEMENT TIME, WORK TIME, AND THE POSTREINFORCEMENT PAUSE
Authors: Rider David P. , Kametani Nora N.
Published: March 2006

Six rats were trained with food deliveries contingent upon their pressing a lever and holding it down for fixed, cumulative durations. Hold requirements were varied from 7.5 seconds to 120 seconds. Lever holding was maintained reliably at hold requirements as long as 30 seconds to 105 seconds for different rats. At longer hold requirements, lever holding was erratic and tended to occur only early in sessions. At shorter and intermediate requirements, the patterns of lever holding resembled those of responding under fixed‐ratio schedules for discrete responses, with breaks in responding immediately after reinforcement alternating with relatively continuous lever holding until the next reinforcement. At longer hold requirements, postpause lever holding frequently was interrupted with additional pauses. The duration of postreinforcement pauses increased linearly with the scheduled hold requirement. However, for five of six rats, the hold requirement, which represents the actual time spent lever holding per reinforcer, accounted for somewhat less variance in pause duration than did interreinforcement time.
CHOICE AND TRANSFORMED INTERREINFORCEMENT INTERVALS
Authors: Moore Jay
Published: March 2006

Pigeons chose between two aperiodic, time‐based schedules of reinforcement. The arithmetic mean interreinforcement interval of the first schedule was short, but the harmonic mean was long, whereas the arithmetic mean interreinforcement interval of the second schedule was long, but the harmonic mean was short. The pigeons preferred the schedule with the shorter harmonic mean in a concurrent‐chains procedure when a terminal link ended after the first scheduled reinforcer had been gained on a terminal‐link entry, but reversed their preferences, such that they preferred the schedule with the shorter arithmetic mean, when the terminal links ended after a fixed duration of exposure to the schedule. Moreover, the pigeons preferred the schedule with the shorter arithmetic mean in a two‐key concurrent variable‐interval variable‐interval procedure, as well as in a concurrent variable‐time variable‐time, changeover‐key procedure. The data suggest that an aggregate property of a schedule may not yield valid information about the responding that schedule will maintain as a choice alternative.
PENTOBARBITAL SELF‐ADMINISTRATION IN RHESUS MONKEYS: DRUG CONCENTRATION AND FIXED‐RATIO SIZE INTERACTIONS
Authors: Lemaire Gregory A. , Meisch Richard A.
Published: March 2006

Performances of three rhesus monkeys were reinforced by the oral delivery of pentobarbital and studied as functions of fixed‐ratio size and drug concentration. Pentobarbital solutions and water were concurrently available on identical reinforcement schedules from separate liquid‐delivery systems during 3‐hour sessions. Under a fixed‐ratio 16 schedule of drug availability, a descending series of drug concentrations was tested (4, 2, 1, 0.5, 0.25, 0.125, and 0.0625 mg/ml, followed by a retest at 4 mg/ml). Partial concentration series beginning with the highest concentration were repeated with fixed‐ratios of 32 and 64, with a fixed‐ratio 128 for two monkeys, and with fixed‐ratio 256 for one. At each fixed‐ratio value, response rate and number of drug deliveries were inverted U‐shaped functions of pentobarbital concentration. Drug intake (mg/kg/session) increased directly with drug concentration. As the fixed‐ratio size was increased, the number of liquid deliveries decreased. For each drug concentration, when the numbers of drug deliveries at fixed‐ratios of 32, 64, and 128 responses were plotted as percentages of those obtained at fixed‐ratio 16, the following orderly relationship emerged: the higher the drug concentration, the less that drug deliveries were decreased by increases in fixed‐ratio size. This relationship indicates an increase in reinforcing efficacy with increases in pentobarbital concentration.
MELIORATION AND SELF‐EXPERIMENTATION
Authors: Neuringer Allen
Published: March 2006

Operant researchers rarely use the arena of applied psychology to motivate or to judge their research. Absence of tests by application weakens the field of basic operant research. Early in their development, the physical and biological sciences emphasized meliorative aspects of research. Improvement of human life was a major goal of these young sciences. This paper argues that if basic operant researchers analogously invoked a melioration criterion, the operant field might avoid its tendency toward ingrowth and instead generate a broadly influential science. Operant researchers could incorporate melioration by (a) creating animal models to study applied problems; (b) confronting questions raised by applied analysts and testing hypotheses in applied settings; or (c) performing self‐experiments — that is, using experimental methods and behavioral techniques to study and change the experimenter's behavior.
THE OPERANT‐RESPONDENT DISTINCTION: FUTURE DIRECTIONS
Authors: Pear Joseph J. , Eldridge Gloria D.
Published: March 2006

The operant‐respondent distinction has provided a major organizing framework for the data generated through the experimental analysis of behavior. Problems have been encountered, however, in using it as an explanatory concept for such phenomena as avoidance and conditioned suppression. Data now exist that do not fit neatly into the framework. Moreover, the discovery of autoshaping has highlighted difficulties in isolating the two types of behavior and conditioning. Despite these problems, the operant‐respondent framework remains the most successful paradigm currently available for organizing behavioral data. Research and theoretical efforts should therefore probably be directed to modifying the framework to account for disparate data.
RATE DEPENDENCY, BEHAVIORAL MECHANISMS, AND BEHAVIORAL PHARMACOLOGY
Authors: Branch Marc N.
Published: March 2006

Behavioral pharmacology has become increasingly independent of the experimental analysis of behavior. At its beginning, behavioral pharmacology was closely related to the experimental analysis of behavior, with developments in each field aiding the other. Early attempts to systematize data in behavioral pharmacology culminated with the development of the rate‐dependency concept, but as this principle was found to have more limited generality than originally was hoped, a theoretical void developed. This circumstance was followed by increased reliance on pharmacological theory as a basis for experimentation and interpretation, with an attendant decrease in emphasis on environmental variables and behavioral interpretations. Lack of interplay between behavioral pharmacology and the experimental analysis of behavior is detrimental to both disciplines because each could contribute significantly to the other. The current trend might be reversed if more research were directed at elucidating behavioral mechanisms of drug action.
SHOCK INTENSITY AND SIGNALED AVOIDANCE RESPONDING
Authors: de Souza Deisy das Graças , de Moraes Antonio Bento Alves , Todorov João Claudio
Published: March 2006

Five rats were submitted to a signaled free‐operant avoidance contingency. Throughout the experiment, shock intensity was varied from 0.1 to 8.0 mA, with shock duration constant at 200 milleseconds. Results indicate: (a) an all‐or‐none effect of shock intensity on response and shock rates, on percentage of shocks avoided, and on frequency of occurrence of responding during the preshock stimulus; and (b) no systematic effect of shock intensity on stimulus control, measured either by the percentage of stimulus presentations accompanied by a response or by the percentage of responses that occurred during those preshock stimuli. Such results indicate that for each subject there is a minimum shock intensity necessary to establish and maintain avoidance responding; intensities higher than this minimum value have little or no effect on responding (with an upper limit for those strong intensities with a general disruptive effect on behavior).
CONCURRENT PHENCYCLIDINE AND SACCHARIN ACCESS: PRESENTATION OF AN ALTERNATIVE REINFORCER REDUCES DRUG INTAKE
Authors: Carroll Marilyn E.
Published: March 2006

Six monkeys self‐administered orally delivered phencyclidine (“angel dust”) and saccharin under concurrent fixed‐ratio 16 schedules during daily three‐hour sessions. Liquid deliveries were contingent upon lip‐contact responses on solenoid‐operated drinking spouts. Three saccharin concentrations (0.003%, 0.03% and 0.3%, wt/vol) were tested in a nonsystematic order. For each saccharin concentration, the following series of phencyclidine concentrations (mg/ml) was presented: 0.25, 0.5, 1, 0.25 (retest), 0.125, 0.0625, 0.0312, 0.25 (retest) and 0 (water with stimuli signaling phencyclidine). As the saccharin concentration increased, the number of drug deliveries decreased, and the peaks of the concentration‐response functions were shifted to the right. The lowest saccharin concentration (0.003%, wt/vol) maintained responding in excess of phencyclidine levels in only one monkey. The two higher saccharin concentrations maintained behavior far in excess of phencyclidine, but saccharin deliveries decreased in some monkeys as phencyclidine concentration and intake (mg/kg) increased. The time course and patterns of phencyclidine‐reinforced responding were also altered when saccharin was concurrently available. The results are discussed in terms of strategies to reduce drug‐reinforced behavior, preference between different reinforcers, and measures of reinforcing efficacy.
EFFECTS OF UNINSTRUCTED VERBAL BEHAVIOR ON NONVERBAL RESPONDING: CONTINGENCY DESCRIPTIONS VERSUS PERFORMANCE DESCRIPTIONS
Authors: Matthews Byron A. , Catania A. Charles , Shimoff Eliot
Published: March 2006

Undergraduates' button presses occasionally made available points that were exchangeable for money. Lights over left and right buttons were respectively correlated with multiple random‐ratio random‐interval components. During interruptions of the multiple schedule, students filled out sentence‐completion guess sheets. When shaping of these guesses produced performance descriptions (e.g., “press slowly” for the left button and “press fast” for the right), button‐pressing rates typically were consistent with the verbal behavior even when rates were opposite to those ordinarily maintained by the respective schedules. When shaping instead produced contingency descriptions (e.g., the button works “after a random number of presses” or “a random time since it worked before”), pressing rates were inconsistently related to the descriptions; for some students descriptions of ratio contingencies generated higher corresponding pressing rates than were produced by descriptions of interval contingencies, but for others contingency descriptions and pressing rates were unrelated.
THE ROLE OF VERBAL BEHAVIOR IN HUMAN LEARNING: II DEVELOPMENTAL DIFFERENCES
Authors: Bentall R. P. , Lowe C. Fergus , Beasty Allan
Published: March 2006

When children in four different age ranges operated a response device, reinforcers were presented according to fixed‐interval schedules ranging in value from 10 to 70 seconds. Only the behavior of the subjects in the youngest of the four groups, the preverbal infants, resembled that of other animal species. The children in age ranges 5 to 6 ½ and 7 ½ to 9 years exhibited either the low‐rate or high‐rate response patterns typical of human adults. Those who showed the low‐rate pattern reported a time‐based formulation of the contingencies and some of them were observed to occasionally count out the interval before responding. The performance of children aged 2 ½ to 4 years differed from that of both infants and older children, though containing some patterning elements similar to those produced by the older and younger subjects. The predominant response pattern of the infants consisted of a pause after reinforcement followed by an accelerated rate of responding that terminated when the next reinforcer was delivered. Analysis of postreinforcement‐pause duration and response rate showed that infant performance, but not that of the older children, consistently exhibited the same kinds of schedule sensitivity observed in animal behavior. The evidence supports the suggestion that the development of verbal behavior greatly alters human operant performance and may account for many of the differences found between human and animal learning.
SIX‐MEMBER STIMULUS CLASSES GENERATED BY CONDITIONAL‐DISCRIMINATION PROCEDURES
Authors: Sidman Murray , Kirk Barbara , Willson‐Morris Martha
Published: March 2006

In conditional‐discrimination procedures with three sets of stimuli, A, B, and C, three stimuli per set (A1A2A3, B1B2B3, and ClC2C3), subjects (children and adults) learned to select Set‐B and Set‐C comparisons conditionally upon Set‐A samples (AlBI, AIC1, A2B2, A2C2, A3B3, A3C3). If the conditional‐discrimination procedures also generated equivalence relations, three 3‐member stimulus classes would be demonstrable, AlBICI, A2B2C2, and A3B3C3. In addition to these three sets, the present experiments used three other sets of stimuli‐D, E, and F. The subjects learned to select Set‐E and Set‐F comparisons conditionally upon Set‐D samples (D1EI, D1FI, D2E2, D2F2, D3E3, D3F3). This established a second group of three 3‐member stimulus classes, D1ElF1, D2E2F2, and D3E3F3. In all, two groups of three 3‐member classes were established by teaching subjects 12 conditional discriminations. The two groups of 3‐member classes were then combined (successfully for 5 of 8 subjects) into a single group of three 6‐member classes by teaching the subjects three more conditional relations (E1C1, E2C2, and E3C3). With three other children, enlarging the classes one member at a time also produced 6‐member classes. As a consequence of class formation, 60 untrained conditional relations emerged from 15 that had been explicitly taught. Six of the subjects also proved capable of naming the stimuli consistently in accord with their class membership, but two subjects demonstrated class formation even in the absence of consistent naming.
VARIATION IN HERRNSTEIN'S ro AS A FUNCTION OF ALTERNATIVE REINFORCEMENT RATE
Authors: Dougan James D. , McSweeney Frances K.
Published: March 2006

In a test of Herrnstein's (1970, 1974) equation for simple schedules, 15 pigeons pecked a key that produced food delivered according to variable‐interval schedules. One group of birds was water deprived, and food‐reinforced key pecking occurred in the presence of free water. Two other groups were not water deprived; water was present for one and absent for the other. As predicted by Herrnstein, the parameter ro was significantly higher in the water‐deprived group than in the two nondeprived groups. Contrary to Herrnstein's interpretation of ro, the rate of drinking varied across schedules. Herrnstein's interpretation can be salvaged by considering ro to be an average. However, if ro is an average, the equation is not a good explanation of behavior because this average is not valid until all schedules have been sampled. In addition, low percentages of variance accounted for suggest that Herrnstein's equation may be of limited usefulness even as a descriptive model for these situations.
THE ROLES OF STIMULUS CONTROL AND REINFORCEMENT FREQUENCY IN MODULATING THE BEHAVIORAL EFFECTS OF d‐AMPHETAMINE IN THE RAT
Authors: Rees David C. , Wood Ronald W. , Laties Victor G.
Published: March 2006

The behavioral effects of d‐amphetamine have been shown to be modulated by stimulus control, with less impairment of performance occurring when control is great. When the fixed‐consecutive‐number schedule is used (on which at least a specified consecutive number of responses must be made on one operandum before a single response on another will produce a reinforcer), response rate tends to be invariant but reinforcement frequency is not. This study asks whether the differences in reinforcement frequency that usually accompany changes in stimulus control could themselves be responsible for the performance differences. Two versions of the fixed‐consecutive‐number schedule of reinforcement were combined into a multiple schedule within which stimulus control was varied but differences in reinforcement frequency were minimized by omitting some reinforcer deliveries during the component that usually had the higher reinforcement frequency. In one component, a compound discriminative stimulus was added with the eighth consecutive response on the first lever; a single response on the second lever was then reinforced. In the other component, no such stimulus was presented. With no added stimulus, large decreases occurred in the number of runs satisfying the minimum requirement for reinforcement at doses of drug that produced only minimal changes when an added stimulus controlled behavior. Thus, increased stimulus control diminishes the behavioral changes produced by d‐amphetamine even when the possible contribution by baseline reinforcement rate is minimized.
AN INFRARED SYSTEM FOR THE DETECTION OF A PIGEON'S PECKS AT ALPHANUMERIC CHARACTERS ON A TV SCREEN: THE DEPENDENCY OF LETTER DETECTION ON THE PREDICTABILITY OF ONE LETTER BY ANOTHER
Authors: Clauson H. D. , Izatt E. J. , Shimp C. P.
Published: March 2006

Three pigeons pecked at letters of the alphabet and at the symbol “?” displayed on a computer‐driven cathode ray screen. A 4 by 4 matrix of infrared emitting and detecting diodes and associated circuitry identified the location of a pigeon's responses to the screen. Responses at the target letter T were probabilistically reinforced with food whenever T appeared in a string of three letters in the middle of the screen. Responses at the symbol “?” appearing below this string were probabilistically reinforced whenever T did not appear. The letter F anywhere in the three‐character string either strongly predicted the occurrence of the target letter T, in two conditions, or predicted its nonoccurrence, in a third. This manipulation of the frequency with which the familiar letter F predicted T was shown to change the function relating probability of a correct peck at the symbol “?” to the number of Fs in the string. This effect may be interpreted as an instance of the phenomenon where an organism's acquired knowledge changes what it sees.
CONTROL OF RESPONDING BY THE LOCATION OF SOUND: ROLE OF BINAURAL CUES
Authors: Burlile C. J. , Feldman M. L. , Craig C. , Harrison J. M.
Published: March 2006

In auditory localization experiments, where the subject observes from a fixed position, both relative sound intensity and arrival time at the two ears determine the extent of localization performance. The present experiment investigated the role of binaural cues in a different context, the sound‐position discrimination task, where the subject is free to move and interact with the sound source. The role of binaural cues was investigated in rats by producing an interaural imbalance through unilateral removal of the middle auditory ossicle (incus) prior to discrimination training. Discrete trial go‐right/go‐left sound‐position discrimination of unilaterally incudectomised rats was then compared with that of normal rats and of rats with the incus of both sides removed. While bilateral incus removal affected binaural intensity and arrival times, the symmetry of sound input between the two ears was preserved. Percentage of correct responses and videotaped observations of sound approach and exploration showed that the unilateral rats failed to localize the sounding speaker. Rats with symmetrical binaural input (normal and bilaterally incudectomised rats) accurately discriminated sound position for the duration of the experiment. Previously reported monaural localization based upon following the intensity gradient to the sound source was not observed in the unilaterally incudectomised rats of the present experiment. It is concluded that sound‐position discrimination depends upon the use of binaural cues.
INTERRESPONSE‐TIME ANALYSIS OF STIMULUS CONTROL IN MULTIPLE SCHEDULES
Authors: White K. Geoffrey
Published: March 2006

Interresponse‐time distributions were recorded in two components of multiple variable‐interval schedules that were varied over several conditions. Values of the exponent for power functions relating ratios of interresponse times emitted per opportunity to ratios of reinforcers obtained in the two components varied with interresponse‐time class interval. The exponent (sensitivity to reinforcement) afforded a measure of stimulus control exerted by the discriminative stimuli. Exponents were near zero for short interresponse times, consistent with previous conclusions that responses following short interresponse times are controlled by response‐produced or proprioceptive stimuli. Values of exponents increased with longer interresponse times, indicating strong control by exteroceptive stimuli over responses following interresponse times of approximately one second or longer.
PROBABILITY AND DELAY OF REINFORCEMENT AS FACTORS IN DISCRETE‐TRIAL CHOICE
Authors: Mazur James E.
Published: March 2006

Pigeons chose between two alternatives that differed in the probability of reinforcement and the delay to reinforcement. A peck on the red key always produced a delay of 5 s and then a possible reinforcer. The probability of reinforcement for responding on this key varied from .05 to 1.0 in different conditions. A response on the green key produced a delay of adjustable duration and then a possible reinforcer, with the probability of reinforcement ranging from .25 to 1.0 in different conditions. The green‐key delay was increased or decreased many times per session, depending on a subject's previous choices. The purpose of these adjustments was to estimate an indifference point, or a delay that resulted in a subject's choosing each alternative about equally often. In conditions where the probability of reinforcement was five times higher on the green key, the green‐key delay averaged about 12 s at the indifference point. In conditions where the probability of reinforcement was twice as high on the green key, the green‐key delay at the indifference point was about 8 s with high probabilities and about 6 s with low probabilities. An analysis based on these results and those from studies on delay of reinforcement suggests that pigeons' choices are relatively insensitive to variations in the probability of reinforcement between .2 and 1.0, but quite sensitive to variations in probability between .2 and 0.
THE ROLE OF OBSERVING AND ATTENTION IN ESTABLISHING STIMULUS CONTROL
Authors: Dinsmoor James A.
Published: March 2006

Early theorists (Skinner, Spence) interpreted discrimination learning in terms of the strengthening of the response to one stimulus and its weakening to the other. But this analysis does not account for the increasing independence of the two performances as training continues or for increases in control by dimensions of a stimulus other than the one used in training. Correlation of stimuli with different densities of reinforcement produces an increase in the behavior necessary to observe them, and greater observing of and attending to the relevant stimuli may account for the increase in control by these stimuli. The observing analysis also encompasses errorless training, and the selective nature of observing explains the feature‐positive effect and the relatively shallow gradients of generalization generated by negative discriminative stimuli. The effectiveness of the observing analysis in handling these special cases adds to the converging lines of evidence supporting its integrative power and thus its validity.
THE FUNCTIONAL INDEPENDENCE OF MANDS AND TACTS
Authors: Lamarre Jennifer , Holland James G.
Published: March 2006

This study demonstrates functional independence in the acquisition of mands and tacts. Some subjects first learned to mand the experimenter's placement of objects with the prepositional phrases “On the left” and “On the right.” They were regularly tested for collateral appearance of tacts with these same phrases. Other subjects learned to tact the location of objects with these prepositional phrases and were regularly tested for collateral appearance of mands. All subjects were next trained in the repertoire that had not been trained in the first condition (either tact or mand). After all subjects had learned both to mand and to tact correctly, another assessment of mand‐tact independence was undertaken. Mands (tacts) were reversed and testing assessed collateral reversal of tacts (mands). The results demonstrated that tacts and mands, even when incorporating identical response forms, were functionally independent during acquisition. Subsequent modification of one repertoire (by reversal training) produced collateral reversal in three of nine subjects.
MATCHING AND MAXIMIZING WITH VARIABLE‐TIME SCHEDULES
Authors: DeCarlo Lawrence T.
Published: March 2006

Pigeons were offered choices between a variable‐time schedule that arranged reinforcers throughout the session and a variable‐time schedule that arranged reinforcers only when the pigeon was spending time on it. The subjects could maximize the overall rate of reinforcement in this situation by biasing their time allocation towards the latter schedule. This arrangement provides an alternative to concurrent variable‐interval variable‐ratio schedules for testing whether animals maximize overall rates or match relative rates, and has the advantage of being free of the asymmetrical response requirements present with those schedules. The results were contrary to those predicted by maximizing: The bias it predicts did not appear.
LEVELS OF AGGREGATION: RELATIVE TIME ALLOCATION IN CONCURRENT‐SCHEDULE PERFORMANCE
Authors: Real Pamela G. , Dreyfus Leon R.
Published: March 2006

The proportion of time allocated to one component of a concurrent variable‐interval variable‐interval schedule was computed for groups of interchangeover times (aggregates) within several intact time series. Variability in obtained proportions decreased as the number of interchangeover times within each aggregate increased; however, modal proportions failed to correspond to overall relative time allocation computed over the course of an entire experimental session, even at the largest aggregate size. The aggregated time series showed periodicities at small aggregate sizes and general trends in local preference at larger aggregate sizes. It is suggested that overall relative time allocation represents a molar extreme in the aggregation of behavior that may not accurately reflect central tendency in the allocation of time to available alternatives within the context of ongoing behavior.
COMPONENT PROBABILITY AND COMPONENT REINFORCER RATE AS BIASERS OF FREE‐OPERANT DETECTION
Authors: Davison Michael , McCarthy Dianne , Jensen Chris
Published: March 2006

Six pigeons were trained on multiple schedules whose components were concurrent variable‐interval extinction and concurrent extinction variable‐interval schedules. In Experiments 1a and 1b the stimuli signaling the components were two different light intensities, and in Experiments 2a and 2b they were two identical intensities. The components of the multiple schedule changed probabilistically after each reinforcer. In Experiments 1a and 2a, the probability of presenting the components was varied over five conditions and a replication. In Experiments 1b and 2b, the component probability was .5 and the component reinforcer rates were varied systematically over five conditions and a replication. The data, analyzed according to the Davison‐Tustin behavioral detection model, confirmed that the discriminability of the stimuli signaling the components was high when the stimuli were different, and low when the stimuli were the same. Discriminability, measured by log d, was unaffected by component probability variation and by component reinforcerrate variation. When discriminability was high, bias, or the response allocation between the two keys, was more strongly affected by variation of reinforcer rate within components than by variation of component probability, but the reverse was found when discriminability was low. The results suggest that free‐operant detection performance is controlled by the rates of reinforcers in periods of time in which stimuli signal differential contingencies. These periods comprise the components when the component stimuli are discriminable, and comprise the total session when the components are indiscriminable. An extension of the Davison‐Tustin behavioral detection model that incorporates these results is presented.
AMOUNT CONSUMED VARIES AS A FUNCTION OF FEEDER DESIGN
Authors: Epstein Robert
Published: March 2006

Studies of pigeon behavior in which magazine‐cycle duration is varied suggest that many researchers assume that feeders of different designs dispense food at roughly the same rate. However, Epstein (1981) showed that, with a commonly used feeder, the amount of grain a pigeon consumes is a negatively accelerated function of magazine‐cycle duration. The present experiment shows that, with a different commonly used feeder, amount consumed is roughly a linear function of magazine‐cycle duration. At a duration of 60 seconds, the second feeder dispenses roughly 10 times as much food as the first. Thus, reports of studies in which magazine‐cycle duration is varied should identify the design of the feeder employed, and in some cases, authors should consider determining the feeding functions for those feeders.
HANDLING TIME AND CHOICE IN PIGEONS
Authors: Shettleworth Sara J.
Published: March 2006

According to optimal foraging theory, animals should prefer food items with the highest ratios of energy intake to handling time. When single items have negligible handling times, one large item should be preferred to a collection of small ones of equivalent total weight. However, when pigeons were offered such a choice on equal concurrent variable‐interval schedules in a shuttlebox, they preferred the side offering many small items per reinforcement to that offering one or a few relatively large items. This preference was still evident on concurrent fixed‐cumulative‐duration schedules in which choosing the alternative with longer handling time substantially lowered the rate of food intake.
CONTROL OF MYOELECTRICAL RESPONSES THROUGH REINFORCEMENT
Authors: Laurenti‐Lions Lila , Gallego Jorge , Chambille Bernard , Vardon Guy , Jacquemin Charles
Published: March 2006

A classic experiment by Hefferline, Keenan, and Harford (1959) showed that small thumb‐twitches, imperceptible to the subject, can be controlled by the consequences of terminating and/or postponing aversive noise. These findings were further investigated in three experiments reported here. Experiment 1 replicated the original study. Experiment 2 was a control study in which stimulus changes were presented as in Experiment 1, but independently of the responses. Under these conditions the response rate varied over a large range with no systematic relation to experimental events. The increments in response rate reported by Hefferline et al. were within the present range of variation, suggesting that conditioning in the earlier study may have reflected a consistency in the direction of change rather than an increase in rate beyond the baseline range. In the present experiment, however, the rate increase was absolute. In Experiment 3, analog rather than binary changes in stimulus conditions were used as reinforcement. Under these conditions, the rates of subjects whose responses were conditioned fell from 78% (in the previous experiment) to 31%.
EFFECTS OF NUTRITIONAL AND MECHANICAL PROPERTIES OF FOOD ON RUMINATIVE BEHAVIOR
Authors: Rast Jim , Johnston James M. , Allen Julia Ellinger , Drum Cheryl
Published: March 2006

Previous studies have identified a reliable relation between the quantity of food ingested and ruminating in profoundly retarded individuals and have established some parametric characteristics of this relation. The present study investigated three different properties of food that may influence this relation. Experiment 1 examined the role of stomach distention produced by including in the subject's diet wheat bran in amounts equivalent to and exceeding the calculated amount of crude fiber in the starch‐satiation diet reported by Rast, Johnston, Drum, and Conrin (1981) and Rast, Johnston, and Drum (1984). There was a decrease in ruminating, although this decrease was smaller and more gradual than in the starch‐satiation condition. Experiment 2 showed that increasing calories without increasing food volume resulted in a gradual and moderate decrease in ruminating. Experiment 3 replicated and extended the first two experiments by varying both caloric intake and stomach distention as well as oropharyngeal and esophageal stimulation in a different sequence of conditions. All variables exerted some control over responding. However, the large and immediate effects of the starch‐satiation procedure occurred only when subjects were permitted to consume unlimited quantities.
THE QUANTAL NATURE OF CONTROLLING STIMULUS‐RESPONSE RELATIONS AS MEASURED IN TESTS OF STIMULUS GENERALIZATION1
Authors: Bickel Warren K. , Etzel Barbara C.
Published: March 2006

This paper is a selective review of research that addresses the validity of two interpretations of stimulus generalization. One interpretation, referred to as the descriptive stimulus‐control interpretation, proposes that during stimulus generalization a continuous relation exists between stimulus and response dimensions. The other interpretation, referred to as the quantal interpretation, proposes that a stimulus‐response relation functions as a unit that may or may not occur. From the latter viewpoint, the continuity typically obtained during generalization tests is deemed to be artifactual and to result from averaging across multiple controlling stimulus‐response relations. Studies examining the contribution of these multiple relations to generalization gradients are reviewed. With few exceptions, the quantal interpretation appears to better characterize the results of these studies. Implications for peak shift, selection of analytical level, and identification of the behavioral unit are discussed, as well as factors that may determine the acceptability of the quantal interpretation.
LOCAL TEMPORAL PATTERNING OF OPERANT BEHAVIOR IN HUMANS
Authors: Wearden John H. , Shimp Charles P.
Published: March 2006

Button pressing by 44 college students intermittently produced points and the words “GOOD” or “POOR” on a computer screen. The events were arranged according to a paced random‐interval 10‐s schedule in which the target interresponse‐time categories were 1 to 3, 3 to 5, or 6 to 12 s. The degree to which instructions specified certain aspects of the contingency (e.g., whether response spacing was critical) was also varied, and in some conditions the experimenter prompted specifically paced responses during the first 2 min of the session. The procedures shaped the local patterning of behavior of some subjects in less than 30 min of exposure to the contingencies. Most subjects who, in a postexperimental questionnaire, accurately identified the schedule contingencies also responded more accurately than those whose verbal descriptions were inaccurate or imprecise.
SOME PARAMETERS OF BEHAVIORAL CONTRAST AND ALLOCATION OF INTERIM BEHAVIOR IN RATS
Authors: Dougan James D. , McSweeney Frances K. , Farmer Valeri A.
Published: March 2006

Two experiments examined the effects of baseline reinforcement rate and component duration on behavioral contrast and on re‐allocation of interim behavior in rats. Positive behavioral contrast occurred during multiple variable‐interval 10‐second extinction (VI 10 EXT) after a multiple VI 10 VI 10 baseline condition, but not during multiple VI 60 EXT following multiple VI 60 VI 60 baseline. Component duration had no significant effect on contrast. These results differed from those found in studies of pigeons' key pecking. Contrast was accompanied by an increased rate of drinking in the changed component, but drinking in the constant component did not decrease. These results are not consistent with the competition theory of contrast, but are consistent with the predictions based on the matching law. However, no current theory seems to account for all instances of behavioral contrast.
PERFORMANCE IN CONTINUOUSLY AVAILABLE MULTIPLE SCHEDULES
Authors: Elliffe Douglas , Davison Michael
Published: March 2006

Three pigeons were given continuous access in their home cages to food reinforcement on two‐component multiple variable‐interval variable‐interval schedules. The reinforcer rates in the two components were varied over seven experimental conditions, and a partial replication over five conditions was arranged one year later. When component reinforcer rates were unequal, ratios of component response rates were more extreme than ratios of obtained component reinforcer rates, a result which in a generalized‐matching analysis is termed overmatching. This finding contrasts sharply with results obtained when multiple schedules are arranged in shorter sessions, in which performance is characterized by undermatching when subjects are deprived of food, and by matching, or equality between component response‐ and reinforcer‐rate ratios, when deprivation is minimal. More molecular data obtained in two subsequent conditions suggested that this finding did not reflect local fluctuations or asymmetries in deprivation. Theories of multiple‐schedule performance that predict that matching cannot be exceeded are disconfirmed by the present results.