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.     

Context-dependent variation in social stereotyping 1: The effects of intergroup relations as mediated by social change and frame of reference

During the 1990-1991 Persian Gulf conflict an experiment was conducted with Australian university students (N = 200) to investigate whether the social stereotyping of Americans varied with social contextual manipulations related to the hostilities. The study, conducted in two phases at the start and end of the conflict, examined how the assignment of standard stereotypical traits to Americans was affected (a) by the large-scale social change constituted by the war and (b) by variation in the frame of reference provided by relevant comparison groups. The elicited stereotypes were sensitive to both of these contextual variables, demonstrating significant variation and fluidity. Overall, stereotypes of Americans were relatively negative. They were significantly more negative (a) at the end of the war than at the beginning in the restricted frame (when Australia and Britain were comparison groups) and (b) in the first phase of the conflict when the frame was extended to include Iraq as a comparison group. The findings were in line with expectations derived from self-categorization theory (Turner, 1985) that the social categorization of self and other into ingroup and outgroup is inherently variable, comparative and context-dependent. They question the long-held view of stereotypes as fixed, rigid and resistant to change.     

The psychological present

The present paper compares behavior-analytic and cognitive treatments of the concept of psychological history with regard to its role in current action. Both treatments take the position that the past bears some responsibility for the present, and are thereby obligated to find a means of actualizing the past in the present. Both do so by arguing that the past is brought to bear in the present via the organism. Although the arguments of the two positions differ on this issue, neither provides a complete account. An unconventional treatment of psychological history is proposed, the logic of which is exemplified in anthropological, biological, and psychological perspectives. The unconventional treatment in psychological perspective holds that (a) the organism's interaction with its environment, not the organism itself, changes with experience; and (b) the past interactions of an organism exist as, and only as, the present interactions of that organism. This solution to the problem of psychological history provides obligations and opportunities for analysis that are not available when the more conventional positions of cognitivism and behavior analysis are adopted.     

Parallel discrimination of subjective contours defined by offset gratings

Recent physiological studies (von der Heydt & Peterhans, 1989) suggest that the orientation of subjective contours is encoded very early in the visual system (V2 in monkey). This result is seemingly at odds with existing psychophysical data which suggest that the detection of subjective contours involves selective attention. It is argued that certain subjective contours are registered in a reflexive (bottom-up) manner by the visual system but that selective attention may be needed to gain access to this representation. To assess this suggestion, a visual-search task was used in which subjects were to detect the presence of a horizontal (vertical) subjective contour (defined by offset gratings) in a variable number of vertical (horizontal) subjective contours (also defined by offset gratings). When there were no competing organizations within the display, detection was indeed independent of the number of nontarget distractors, that is, selective attention was unnecessary. In a second experiment, we found that a curved form (a crescent defined by subjective contours) was easier to detect in a background of vertical bars (also defined by subjective contours) than vice versa, namely, a search asymmetry paralleling those found by Treisman and Gormican (1988). A final experiment showed that when the horizontal and vertical bars of the first experiment formed textured regions, they could be discriminated at very brief display durations (30–120 msec), However, when the line terminations aligned along the subjective contour were tapered rather than abrupt, discrimination dropped off with the degree of tapering. The latter result is consistent with the assumption that the registration of subjective contours in V2 involves the integration of responses from aligned, end-stopped cells found in VI (von der Heydt & Peterhans, 1989).     

Mentalism, behavior-behavior relations, and a behavior-analytic view of the purposes of science

In a behavioral view, the purposes of science are primarily prediction and control. To the extent that a scientist embraces both of these as a unified and generally applicable criterion for science, certain philosophical and theoretical practices are counterproductive, including mentalism in both its metaphysical and metatheoretical forms. It is possible and often worthwhile to recast some mentalistic talk into an issue of behavior-behavior relations. When behavior-behavior relations are approached non-mechanistically, however, analysis cannot stop at the level of the relations themselves. Several analytic concepts common in the behavioral community share some of the dangers of mentalism if not employed properly, including such concepts as self-reinforcement, response-produced stimulation, and self-rules.     

Generalization of treatment effects in training public speakers

Three studies compared the efficacy of various treatments for public-speaking incompetence. These effects were evaluated for the target behavior as well as for generalization effects across situations (conversations), settings (different sizes and types of audiences) and time (6-month follow-up). The first study showed that Self-instructional Training, either alone or in combination with other procedures, produced little or no benefits. The second study demonstrated the superiority of a Skills Training program over flooding therapy, while the final study failed to detect any enhancement of treatment benefits for the addition of home-practice to the Skills Training. In the first two studies generalization occurred across the three dimensions (settings, situations and time), while in the final study it was shown that the program was effective for a clinical population as well as recruited volunteers.     

Trading relations in the perception of speech by 5-year-old children

Five-year-old children were tested for perceptual trading relations between a temporal cue (silence duration) and a spectral cue (F₁ onset frequency) for the “say-stay” distinction. Identification functions were obtained for two synthetic “say-stay” continua, each containing systematic variations in the amount of silence following the /s/ noise. In one continuum, the vocalic portion had a lower F₁ onset than in the other continuum. Children showed a smaller trading relation than has been found with adults. They did not differ from adults, however, in their perception of an “ay-day” continuum formed by varying F₁ onset frequency only. The results of a discrimination task in which the two acoustic cues were made to “cooperate” or “conflict” phonetically supported the notion of perceptual equivalence of the temporal and spectral cues along a single phonetic dimension. The results indicate that young children, like adults, perceptually integrate multiple cues to a speech contrast in a phonetically relevant manner, but that they may not give the same perceptual weights to the various cues as do adults.