Staying Together: A Bidirectional Delay–Coupled Approach to Joint Action

To understand how individuals adapt to and anticipate each other in joint tasks, we employ a bidirectional delay–coupled dynamical system that allows for mutual adaptation and anticipation. In delay–coupled systems, anticipation is achieved when one system compares its own time‐delayed behavior, which implicitly includes past information about the other system’s behavior, with the other system’s instantaneous behavior. Applied to joint music performance, the model allows each system to adapt its behavior to the dynamics of the other. Model predictions of asynchrony between two simultaneously produced musical voices were compared with duet pianists’ behavior; each partner performed one voice while auditory feedback perturbations occurred at unpredictable times during live performance. As the model predicted, when auditory feedback from one musical voice was removed, the asynchrony changed: The pianist’s voice that was removed anticipated (preceded) the actions of their partner. When the auditory feedback returned and both musicians could hear each other, they rapidly returned to baseline levels of asynchrony. To understand how the pianists anticipated each other, their performances were fitted by the model to examine change in model parameters (coupling strength, time‐delay). When auditory feedback for one or both voices was removed, the fits showed the expected decrease in coupling strength and time‐delay between the systems. When feedback about the voice(s) returned, the coupling strength and time‐delay returned to baseline. These findings support the idea that when people perform actions together, they do so as a coupled bidirectional anticipatory system.     

Complex Communication Dynamics: Exploring the Structure of an Academic Talk

Communication is a multimodal phenomenon. The cognitive mechanisms supporting it are still understudied. We explored a natural dataset of academic lectures to determine how communication modalities are used and coordinated during the presentation of complex information. Using automated and semi‐automated techniques, we extracted and analyzed, from the videos of 30 speakers, measures capturing the dynamics of their body movement, their slide change rate, and various aspects of their speech (speech rate, articulation rate, fundamental frequency, and intensity). There were consistent but statistically subtle patterns in the use of speech rate, articulation rate, intensity, and body motion across the presentation. Principal component analysis also revealed patterns of system‐like covariation among modalities. These findings, although tentative, do suggest that the cognitive system is integrating body, slides, and speech in a coordinated manner during natural language use. Further research is needed to clarify the specific coordination patterns that occur between the different modalities.     

ACQUISITION AND FUNCTIONAL ANALYSIS OF MANDING WITH AUTISTIC STUDENTS

Three autistic students were trained to request a specific object from an adult “supplier” with the sentence, “Give me —” and to deliver that object to another adult, the “director.” Subsequently, the degree to which the object offered by the supplier controlled the “Give me —” verbal response was assessed by delivering to the student an object other than the one requested. Despite knowing the names of all objects used in the experiment, students accepted and delivered to the director any object offered by the supplier regardless of its match with the requested object. After training to say “That's not it. Give me —” when nonrequested objects were offered, students responded differentially to requested and nonrequested objects, suggesting control of the “Give me —” response by the requested object, a characteristic of a mand. These results generalized across settings and objects. Results are discussed in terms of the training technique to establish manding and the functional analysis of the resulting verbal behavior.     

COVARIATION WITHIN FUNCTIONAL RESPONSE CLASSES: IMPLICATIONS FOR TREATMENT OF SEVERE PROBLEM BEHAVIOR

Two studies examined the effects of a reductive treatment versus instruction-based treatments on the generalized reduction of problem behaviors. Each study involved a detailed analysis of multiple problem behaviors performed by school-aged youth with severe intellectual disabilities. The analysis examined the contrasting effects of one of two different positive intervention procedures (teaching a positive alternative behavior or providing additional teacher assistance during instruction) versus blocking and/or verbally reprimanding a problem behavior. The focus of each analysis was on the covariation of multiple problem behaviors within functional response classes. Results of the investigation indicated that when only one member of the response class was blocked, a collateral increase was observed in one or more different problem behaviors from the same response class. Alternatively, when 1 participant was taught a functionally equivalent mand response, all problem behaviors in the response class were reduced. Problem behaviors also were reduced for the remaining participant by presenting antecedent teacher assistance. Implications of the research extend to analysis of covariation within response classes and to procedures that result in generalized reduction of problem behaviors within a response class.     

AN ANALYSIS OF MAINTENANCE FOLLOWING FUNCTIONAL COMMUNICATION TRAINING

The multiple and long-term effects of functional communication training relative to a common reductive procedure (time-out from positive reinforcement) were evaluated. Twelve children participated in a functional analysis of their challenging behaviors (Study 1), which implicated adult attention as a maintaining variable. The children were then matched for chronological age, mental age, and language age and assigned to two groups. One group received functional communication training as an intervention for their challenging behavior, and the second group received time-out as a contrast. Both interventions were initially successful (Study 2), but durable results were achieved only with the group that received functional communication training across different stimulus conditions (Study 3). Students whose challenging behaviors were previously reduced with time-out resumed these behaviors in the presence of naive teachers unaware of the children's intervention history. The value of teaching communicative responses to promote maintenance is discussed as it relates to the concept of functional equivalence.     

Evaluating young children''s cognitive capacities through computer versus hand drawings

Young normal and handicapped children, aged 3 to 6 years, were taught to draw a scene of a house, garden and a sky with a computer drawing program that uses icons and is operated by a mouse. The drawings were rated by a team of experts on a 7-category scale. The children's computer- and hand-produced drawings were compared with one another and with results on cognitive, visual and fine motor tests. The computer drawing program made it possible for the children to accurately draw closed shapes, to get instant feedback on the adequacy of the drawing, and to make corrections with ease. It was hypothesized that these features would compensate for the young children's limitations in such cognitive skills, as memory, concentration, planning and accomplishment, as well as their weak motor skills. In addition, it was hypothesized that traditional cognitive ratings of hand drawings may underestimate young children's intellectual ability, because drawing by hand demands motor skills and memory, concentration and planning skills that are more developed than that actually shown by young children. To test the latter hypothesis, the children completed a training program in using a computer to make drawings. The results show that cognitive processes such as planning, analysis and synthesis can be investigated by means of a computer drawing program in a way not possible using traditional pencil and paper drawings. It can be said that the method used here made it possible to measure cognitive abilities "under the floor" of what is ordinarily possible by means of traditionally hand drawings.     

TOWARD A NEW RELATION BETWEEN HUMANITY AND NATURE: RECONSTRUCTING T'IEN-JEN-HO-I

Abstract. The traditional Chinese idea of t'ien-jen-ho-i (Heaven and humanity in union) implies that humanity has to live in harmony with nature. As science and technology progress, however, the idea appears increasingly outmoded, and it becomes fashionable to talk about overcoming nature. Ironically, though, the further science reaches the more clearly are its limitations exposed. The exploitation of nature not only endangers many life forms on earth but threatens the very existence of the human species. I propose that a reconstruction of the traditional Chinese idea of T'ien-jen-ho-i will help us envisage a new and salutary relation between humanity and nature.     

Functional classes and equivalence relations

Three adult subjects were taught a set of two-choice simultaneous discriminations, with three positive and three negative stimuli; all possible combinations of positive and negative stimuli yielded nine different pairs. The discriminations were repeatedly reversed and rereversed, the former positive stimuli becoming negative and the former negative stimuli becoming positive. With all subjects, a reversal of the contingencies for one pair of stimuli became sufficient to change their responses to all of the other pairs. The reversals had produced functional stimulus classes. Then, all subjects showed conditional discriminations emerging between members of a functional class; given a sample from one class and comparisons from both classes, they selected the comparison that was in the same class as the sample. Next, 2 of the subjects showed that the within-class conditional relations possessed the symmetric and transitive properties of equivalence relations; after having been taught to relate new stimuli to existing class members, the subjects then matched other class members to the new stimuli. Subsequent tests of two-choice discriminations showed that the conditional discriminations had transferred functional class membership to the new stimuli. The 3rd subject, who did not show equivalence relations among functional class members, was also found to have lost the within-class conditional relations after the equivalence tests.     

The choice of constraints in correspondence analysis

A discussion of alternative constraint systems has been lacking in the literature on correspondence analysis and related techniques. This paper reiterates earlier results that an explicit choice of constraints has to be made which can have important effects on the resulting scores. The paper also presents new results on dealing with missing data and probabilistic category assignment.I am most grateful to the following for their helpful comments. Arto Demirjian, Michael Greenacre, Michael Healy, Shizuhiko Nishisato, Roderick Mcdonald, and several anonymous referees.