The development of derived stimulus relations through training in arbitrary-matching sequences

Five-year-old children were taught three-stage sequences of arbitrary matching: A-C, B-C, A-D; A-C, B-D, B-C; or A-C, A-D, B-C. Each stage refers to a sample-comparison relation between stimuli. Unreinforced test probes revealed untrained arbitrary matches (B-D, A-D, and B-D, respectively), derivable by substitution of stimuli with a common sample or comparison function. Additional probes revealed further untrained sample-comparison relations derivable by substitution and identity, including the commuted relations D-B, D-A, and D-B, respectively. These processes may have relevance to conceptual and verbal behavior.     

Reaction times of younger and older men and temporal contingencies of reinforcement

Influences of extended training and temporal contingencies on reaction time were studied in relation to developmental differences. Older and younger men were trained on a chained schedule in which completion of a variable interval produced a terminal link in which reaction time was measured. The reaction-time procedure involved a conditional discrimination with matching to sample in one component and oddity matching in the other. During baseline training, no time limit was placed on the response to the discrimination choice stimuli. Subsequently, increasingly severe time limits were imposed over a series of sessions. Older and younger men showed increased speeds (decreased reaction times) when temporal contingencies were imposed, and these changes were maintained during post-training baseline sessions when there was unlimited time in which to respond. The younger men generally responded faster than the older ones, and age differences were not appreciably reduced during the course of the experiment. The results indicated the feasibility of studying reaction time in human subjects using operant procedures analogous to those developed for the study of nonverbal organisms.     

A more powerful method for testing for agreement between a judge and a known standard

We assume that a judge's task is to categorize each ofN subjects into one ofr known classes. The design of primary interest is employed if the judge is presented withs groups, each containingr subjects, such that each group of sizer consists of exactly one subject of each of ther types. The probability distribution for the total number of correct choices is developed and used to test the null hypothesis that the judge is guessing in favor of the alternative that he or she is operating at a better than chance level. The power of the procedure is shown to be superior to two other procedures which appear in the literature.The authors are grateful for the suggestions of the referees and for computer funding provided by the Northeast Regional Data Center at the University of Florida.     

The effects of hand and direction parameter preknowledge on choice reaction times

The two studies undertaken investigated how reaction times are affected by preknowledge concerning hand and direction parameters, and the order in which these data are disclosed. In the first experiment, preknowledge was manipulated by selecting 2-CRT pairs which had either a common hand or direction component. Reaction signal information content (as defined by the number of unknown response parameters) was controlled, but no parameter differences emerged. When parameter order was manipulated by sequential precuing, the ‘hand then direction’ order conferred a significant advantage. Motor preparation and response selection explanations for this effect are considered. Various difficulties with the paradigms used are discussed, including those of distinguishing between response selection and motor programming contributions, controlling and inferring the strategies adopted by subjects, and defining task difficulty. The prospects for independently fostering either response identification or motor preparation by means of an appropriate selection of precues are also discussed.     

CONDITIONAL DISCRIMINATION VS. MATCHING TO SAMPLE: AN EXPANSION OF THE TESTING PARADIGM

A subject's performance under a conditional-discrimination procedure defines conditional relations between stimuli: “If A1, then B1; if A2, then B2.” The procedure may also generate matching to sample. If so, the stimuli will be related not only by conditionality, but by equivalence: A1 and B1 will become equivalent members of one stimulus class, A2 and B2 of another. One paradigm for testing whether a conditional-discrimination procedure has generated equivalence relations uses three sets of stimuli, A, B, and C, three stimuli per set. Subjects learn to select Set-B and Set-C comparisons conditionally upon Set-A samples. Having been explicitly taught six sample-comparison relations, A1B1, A1C1, A2B2, A2C2, A3B3, and A3C3, subjects prove immediately capable of matching the B- and C-stimuli; six new relations emerge (B1C1, B2C2, B3C3, C1B1, C2B2, C3B3). The 12 stimulus relations, six taught and six emergent, define the existence of three three-member stimulus classes, A1B1C1, A2B2C2, and A3B3C3. This paradigm was expanded by introducing three more stimuli (Set D), and teaching eight children not only the AB and AC relations but DC relations also—selecting Set-C comparisons conditionally upon Set-D samples. Six of the children proved immediately capable of matching the B- and D-stimuli to each other. By selecting appropriate Set-B comparisons conditionally upon Set-D samples, and Set-D comparisons conditionally upon Set-B samples, they demonstrated the existence of three four-member stimulus classes, A1B1C1D1, A2B2C2D2, and A3B3C3D3. These larger classes were confirmed by the subjects' success with the prerequisite lower-level conditional relations; they were also able to select Set-D comparisons conditionally upon samples from Sets A and C, and to do the BC and CB matching that defined the original three-member classes. Adding the three DC relations therefore generated 12 more, three each in BD, DB, AD, and CD. Enlarging each class by one member brought about a disproportionate increase in the number of emergent relations. Ancillary oral naming tests suggested that the subject's application of the same name to each stimulus was neither necessary nor sufficient to establish classes of equivalent stimuli.     

A multi-element analysis of the effect of teacher aides in an "open"-style classroom

Open classrooms with few rules, individualized instruction, and informal class organization present new problems for the application of behavior principles. The effects of three types of teacher aides on student achievement and on-task behavior were studied. Each was compared with a standard no-aide condition. Subjects were 54 third graders in two "open"-style classrooms. The three types of aide, helping adult, disciplinary adult, and helping fifth-grade aide, were compared in a multi-element design with a no-aide control. The helping-adult aide significantly affected the academic output of the class, when compared with the no-aide condition. All aide conditions produced more academic work and on-task behavior than did the standard no-aide condition.     

A comparison of frequency, interval, and time-sampling methods of data collection

Data representing high, medium, and low response rates in constant and nonconstant patterns were generated by electromechanical equipment to determine whether the same data collected by time-sampling, interval recording, and frequency recording would be represented similarly by each method. Results indicated: (1) that time-sampling provided an extremely inaccurate estimate of responding, and (2) that interval recording accurately represented responding of low and medium rates, but grossly underestimated high-rate responding.     

MODIFICATION OF THE EXCESSIVE INAPPROPRIATE CLASSROOM BEHAVIOR OF TWO ELEMENTARY SCHOOL STUDENTS USING HOME-BASED CONSEQUENCES AND DAILY REPORT-CARD PROCEDURES1

Two experiments investigated home-based reinforcement contingencies to control excessive behavior in normal classrooms. Subjects were, respectively, a 12-yr-old fifth-grade boy and a 9-yr-old fourth-grade boy, each in a separate classroom and with a different teacher. Following baseline observations in which observers recorded several categories of student behavior and teacher-student interaction, separate conferences were held including parents of the two children, the principal, teachers, and experimenters. A daily report-card procedure was agreed on, stipulating a one-day suspension from school following three successive “undesirable” daily report cards as well as the supervision of home-based privileges and other reinforcers usually contingent on satisfactory daily reports. Measurements of daily rates of teacher attention indicated no important change in this variable throughout the various experimental conditions. The daily report procedure significantly reduced disruptive classroom behavior. In a second experiment, a teacher-operated timer cued her own time-sample observations. Reliability measures revealed that the teacher could accurately measure the child's behavior while she was teaching the class. The procedure was ultimately successfully expanded to the teacher's total contact hours each day.     

Alexithymia as a potential source of symptom over‐reporting: An exploratory study in forensic patients and non‐forensic participants

The traditional interpretation of symptom over‐reporting is that it indicates malingering. We explored a different perspective, namely that over‐reporting of eccentric symptoms is related to deficits in articulating internal experiences (i.e., alexithymia). Given that alexithymia has been linked to sleep problems and that fatigue may fuel inattentive responding to symptom lists, we administered measures of alexithymia (TAS ‐20) and symptom over‐reporting (SIMS ), but also sleep quality (SLEEP ‐50) to forensic psychiatric outpatients (n = 40) and non‐forensic participants (n = 40). Forensic patients scored significantly higher on all three indices than non‐forensic participants. In the total sample as well as in subsamples, over‐reporting correlated positively and significantly with alexithymia, with r s being in the 0.50–0.65 range. Sleep problems were also related to over‐reporting, but in the full sample and in the forensic subsample, alexithymia predicted variance in over‐reporting over and above sleep problems. Although our study is cross‐sectional in nature, its results indicate that alexithymia as a potential source of over‐reporting merits systematic research.