Establishing Functional Classes In A Chimpanzee (Pan troglodytes) With A Two-item Sequential-Responding Procedure

A 9-year-old female chimpanzee was trained on a two-item sequential-responding task. Attempts were made with successive-reversal training to establish functional classes. In Experiment 1, the subject was exposed to between-session successive-reversal training in which one of two pairs of stimuli was reversed, and transfer of reversal responding to the other pair was tested with nonreinforcement probe trials. She did not show transfer during the course of reversals. Stimulus control established in the original training was maintained on nonreinforcement probe trials. In Experiment 2, within-session reversals were introduced. She showed transfer from the initially reversed pair to the other. The results were consistent with Vaughan's (1988) results with pigeons on successive discriminations, which indicated the formation of functional classes. In Experiment 3, crossover and wild-card tests were conducted to clarify the stimulus control of sequential responding. The results suggested that the sequential responding was controlled only by the first stimulus of each pair. To establish control by both first and second stimuli, trial-unique stimuli or wild cards were substituted for one of the items of the lists in Experiment 4. Further transfer tests, in which stimuli for the two new pairs appeared, were also given to the subject. She successfully responded to these two merged lists and reversed the order as the result of reversal training.     

Instructions as discriminative stimuli

Four undergraduates were exposed to a fixed-ratio schedule under an instruction to respond slowly and to a differential-reinforcement-of-low-rate 5-s schedule under an instruction to respond rapidly. Following this, a fixed-interval schedule was in effect under those same two sets of instructions. For 3 of 4 subjects, response rates were higher with the instruction to respond slowly than with the instruction to respond rapidly during the fixed-interval schedule. For the remaining subject, low-rate responding with the instruction to respond rapidly continued during the first 17 reinforcements of the fixed-interval schedule. Such control by instructions was not observed for other subjects exposed only to a fixed-interval schedule, with or without instructions. The results demonstrate that the effect of instructions can be altered by contingencies and suggest that instructions can function as discriminative stimuli.     

Classification of vowels and consonants by individuals with moderate mental retardation: development of arbitrary relations via match-to-sample training with compound stimuli.

This study explored whether an identity-matching-based stimulus equivalence procedure could be used to teach vowel and consonant stimulus classes to 2 adolescent females with moderate mental retardation. Delayed match-to-sample trials presented a compound sample stimulus consisting of printed letters and a spoken word (“vowel” or “consonant”). The correct comparison stimulus matched only one of the letters in the compound sample. Subsequently, test trials assessed whether arbitrary relations had formed among the individual stimuli from each compound sample and whether stimuli from different compound samples had merged into larger stimulus classes. Both participants acquired five-member classes of vowel and consonant stimuli, which subsequently generalized to vocal classification and to identification in the context of four-letter words. Follow-up tests showed that the generalized performances remained intact after 6 weeks. These procedures suggest an economical approach to stimulus class development.     

AUDITORY SUCCESSIVE CONDITIONAL DISCRIMINATION AND AUDITORY STIMULUS EQUIVALENCE CLASSES

This paper describes an experimental demonstration of stimulus equivalence classes consisting entirely of auditory stimuli. Stimuli were digitized arbitrary syllables (e.g., “cug,” “vek”) presented via microcomputer. Training and testing were conducted with a two-choice auditory successive conditional discrimination procedure. On each trial, auditory samples and comparisons were presented successively. As each comparison was presented, a response location (a rectangle) appeared on the computer screen. After all stimuli for a trial were presented, subjects selected one of the response locations. Six subjects acquired the conditional discrimination baseline, 4 subjects demonstrated the formation of three-member auditory equivalence classes resulting from sample-S+ relations, and 1 subject demonstrated equivalence classes resulting from sample-S— relations. Four subjects received additional training and subsequently demonstrated expansion of the three-member classes to four members each.     

Chronic pain relief after receiving affective touch: A single case report

Affective touch is gentle slow stroking of the skin, which can reduce experimentally induced pain. Our participant, suffering from Parkinson's Disease and chronic pain, received 1 week of non-affective touch and 1 week of affective touch as part of a larger study. Interestingly, after 2 days of receiving affective touch, the participant started to feel less pain. After 7 days, the burning painful sensations fully disappeared. This suggest that affective touch may reduce chronic pain in clinical populations.     

Touch by Intrusive and Withdrawn Mothers with Depressive Symptoms

Interaction behaviours of 88 adolescent mothers with depressive symptoms and their 3-month-old infants were videotaped and coded for different types of touch. The ‘depressed’ mothers were classified as intrusive, withdrawm or good by one observer and another observer coded rough tickling, poking, tugging and pulling as negative touch behaviours and gentle stroking and rubbing as positive touch behaviours. The mothers with depressive symptoms were more likely to touch their infants in a negative way and more likely to be classified as intrusive.     

Behavioral momentum in computer-presented discriminations in individuals with severe mental retardation

Behavioral momentum was examined in 2 individuals with severe mental retardation via within-subject manipulations of obtained reinforcer rates. Subjects performed self-paced discrimination problems presented on a touch screen computer monitor. Two different problems, Tasks A and B, alternated in blocks of 15 trials on a multiple schedule. Reinforcers were snack foods. The reinforcement schedule for Task A was continuous (fixed-ratio 1) and the schedule for Task B was continuous in some conditions and variable ratio in other conditions. Behavioral momentum was assessed in test sessions by prefeeding, presenting response-independent food, and making available alternatives to the tasks. When the obtained reinforcer rate for Task A was at least twice that for Task B, resistance to change was greater for Task A. When both reinforcer rates and response rates were a pproximately equal for the two tasks, resistance to change was approximately equal. These results are consistent with behavioral momentum effects. They extend previous findings with humans by examining momentum in self-initiated discrete-trial discrimination tasks with ratio schedules, and by isolating relative reinforcer rates as a controlling variable via within-subject manipulations.     

Is touch a valid therapeutic intervention? Early returns from a qualitative study of therapists' views

Findings are reported from six semi‐structured interviews with experienced psychotherapists, focusing on the reasons for using touch and the sort of touch used. They suggest that there is a distinction being made by therapists between ‘social space’ and ‘therapeutic space’, and a different view of touch taken if it is judged by the therapist to be ‘out of the therapeutic environment’. Whether or not touch was initiated by the therapist or the client would also appear to influence its further discussion by the therapist, either in processing it with the client or in supervision. What also emerged from the interviews was the finding that an exploration of touch in supervision was unusual. The implications for practice, supervision and training are discussed as areas for further exploration in the main survey, which will be conducted in the second year of the research.     

Investigating Maternal Touch and Infants' Self‐Regulatory Behaviours during a Modified Face‐to‐Face Still‐Face with Touch Procedure

Maternal touch and infants' self‐regulatory behaviours were examined during a modified Still‐Face with Touch (SF + T) procedure. Mothers and their 5½‐month‐old infants participated in one period of Normal interaction followed by three SF + T periods. Maternal functions of touch, and infants' self‐regulatory behaviour, affect, and attention were evaluated. Contrary to a typical SF procedure, the amount of smiling remained high while fretting remained low. High levels of maternal touching and variations in the functions of maternal touch were observed across periods. Playful touch remained high while there was an increase in nurturing touch and a decrease in attention‐getting touch from the Normal to all SF + T periods. Similar amounts of self‐regulatory behaviours were observed across periods with the exception of a decrease in bidirectional exchanges during the SF + T periods. Finally, across periods, maternal touch and infants' self‐regulatory behaviours were found to be temporally organized with infants' affect and attention. Examining how mothers use touch when other forms of communication are absent increased our understanding of the role of touch in infants' emotion regulation. Copyright © 2014 John Wiley & Sons, Ltd.