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Functional responses describe how the proportion of prey consumed by a predator changes as prey density changes. For predators consuming a single prey species, functional responses are determined by two parameters: attack rate and handling time. These parameters may be influenced by morphological and behavioral differences in prey stemming from interspecific or environmentally-driven processes. Here we investigate how interspecific morphological differences and changes in movement rate impact a predator’s functional response. Using a flatworm predator (Stenostomum virginianum) consuming either Paramecium aurelia or P. multimicronucleatum we show that movement rate changes significantly with temperature, leading to changes in attack rate. We also show how body size affects the amount of time predators require to handle prey. We fit a mechanistic functional response model to demonstrate how changes in attack rate and handling time affect overall rates of predation. Our results demonstrate that S. virginianum attack rates are greater for P. aurelia than P. multimicronucleatum. In addition, higher temperature increases S. virginianum attack rates on both species, and reduces the time needed to handle P. aurelia. These differences in predation rate appear related to prey species’ traits, and the temperature-mediated changes in these traits, highlighting the complex processes that underpin predator–prey interactions.

On 11 March 2020, the World Health Organization officially declared COVID-19 a pandemic. The new physical distancing rules have had many consequences, some of which are felt throughout the justice system. Courts across the world limited their operations. Nonetheless, given that justice delayed is justice denied, many jurisdictions have turned to technologies for urgent matters. This paper offers an evidence-based comment and caution for lawyers and judges who could be inclined, for concerns such as cost and time saving, to permanently step aside from in-person trials. Using nonverbal communication research, in conjunction with American and Canadian legal principles, we argue that such a decision could harm the integrity of the justice system.

Recent theoretical and experimental work suggests a frictionless-frictional transition with increasing inter-particle pressure explains the extreme solid-like response of discontinuous shear thickening suspensions. However, analysis of macroscopic discontinuous shear thickening flow in geometries other than the standard rheometry tools remain scarce. Here we use a Hele-Shaw cell geometry to visualise gas-driven invasion patterns in discontinuous shear thickening cornstarch suspensions. We plot quantitative results from pattern analysis in a volume fraction-pressure phase diagram and explain them in context of rheological measurements. We observe three distinct pattern morphologies: viscous fingering, dendritic fracturing, and system-wide fracturing, which correspond to the same packing fraction ranges as weak shear thickening, discontinuous shear thickening, and shear-jammed regimes. The microscopic mechanisms underlying the discontinuous shear thickening transition in dense granular systems are still under debate. Here, the authors explore this transition by characterizing the shape of invasion patterns in Hele-Shaw cell experiments with confined cornstarch suspensions.

This article discusses a new systems model of dyadic nonverbal interaction. The model builds on earlier theories by integrating partners’ parallel sending and receiving nonverbal processes into a broader, dynamic ecological system. It does so in two ways. First, it moves the level of description beyond the individual level to the coordination of both partners’ contributions to the interaction. Second, it recognizes that the relationships between (a) individuals’ characteristics and processes and (b) the social ecology of the interaction setting are reciprocal and best analyzed at the systems level. Thus, the systems model attempts to describe and explain the dynamic interplay among individual, dyadic, and environmental processes in nonverbal interactions. The potential utility and the limitations of the systems model are discussed and the implications for future research considered. Although the systems model is focused explicitly on face-to-face nonverbal communication, it has considerable relevance for digital communication. Specifically, this model provides a useful framework for examining the social effects of mobile device use and as a template for studying human–robot interactions.

Mobile communication technology plays an increasingly pervasive role in everyday life. This study examined one aspect of this role, specifically, the effects of mobile device use on the micro-interactions of pedestrians as they approached and passed a confederate. Over 400 participants were observed in a 2 (group: mobile device vs. control) × 3 [condition: look-only (L); look and smile (LS); look, smile, and greeting (LSG)] factorial design study measuring participants’ looks, smiles, nods, and greetings toward the confederates. Log-linear analyses of the dependent measures provided qualified support for the predicted decreased responsiveness from mobile device users. Specifically, a group by condition interaction on smiles showed that significantly fewer mobile device users than controls smiled at the confederates in the LSG condition. In addition, a group by sex of participant interaction on greetings indicated that significantly fewer female mobile device users offered greetings than males and females in the other conditions. The processes potentially mediating these effects are discussed and the broader influence of mobile devices on the micro-interactions of pedestrians is considered.

This article offers a brief, selective review of some important trends and issues in nonverbal research over the last 50 years. Although the volume and range of research have increased dramatically over that period, an adequate integration of this extensive body of work is lacking. In response to this concern, the article proposes that nonverbal communication might be framed in terms of an adaptive and efficient system of managing our social worlds. Several basic characteristics of this system are outlined and their utility in organizing and facilitating research is discussed.

An integrated, computer-based system was developed to record participants’ continuous judgment changes on a revised form of the Interpersonal Perception Task (IPT-15). Consistent with the considerable research on “thin slice” judgments, the mean latency for greater than chance accuracy confidence was just 16 s (median = 10 s) for the ten one-part scenes on the IPT. There was also a clear and strong linear trend for increasing accuracy confidence across the first 25 s of the ten one-part scenes. For the five-two-part scenes, where comparative judgments were required (e.g., which statement is truthful, which is a lie?), no clear pattern of increasing accuracy confidence was found, with mean scores hovering near chance. The utility of the new system for analyzing the time course of social judgments is discussed and the potential reasons for the contrasting results for the one-part and two-part scenes were examined.

The definition of the nerve cell types of the myenteric plexus of the mouse small intestine has become important, as more researchers turn to the use of mice with genetic mutations to analyze roles of specific genes and their products in enteric nervous system function and to investigate animal models of disease. We have used a suite of antibodies to define neurons by their shapes, sizes, and neurochemistry in the myenteric plexus. Anti-Hu antibodies were used to reveal all nerve cells, and the major subpopulations were defined in relation to the Hu-positive neurons. Morphological Type II neurons, revealed by anti-neurofilament and anti-calcitonin gene-related peptide antibodies, represented 26% of neurons. The axons of the Type II neurons projected through the circular muscle and submucosa to the mucosa. The cell bodies were immunoreactive for choline acetyltransferase (ChAT), and their terminals were immunoreactive for vesicular acetylcholine transporter (VAChT). Nitric oxide synthase (NOS) occurred in 29% of nerve cells. Most were also immunoreactive for vasoactive intestinal peptide, but they were not tachykinin (TK)-immunoreactive, and only 10% were ChAT-immunoreactive. Numerous NOS terminals occurred in the circular muscle. We deduced that 90% of NOS neurons were inhibitory motor neurons to the muscle (26% of all neurons) and 10% (3% of all neurons) were interneurons. Calretinin immunoreactivity was found in a high proportion of neurons (52%). Many of these had TK immunoreactivity. Small calretinin neurons were identified as excitatory neurons to the longitudinal muscle (about 20% of neurons, with ChAT/calretinin/+/- TK chemical coding). Excitatory neurons to the circular muscle (about 10% of neurons) had the same coding. Calretinin immunoreactivity also occurred in a proportion of Type II neurons. Thus, over 90% of neurons in the myenteric plexus of the mouse small intestine can be currently identified by their neurochemistry and shape.

This study examined the microinteractions of pedestrians in Japan and in the United States as they walked past a confederate. Specifically, the effects of culture, condition (avoid, look-only, and look plus smile) and sex of confederate on glances, smiles, nods, and greetings by passing pedestrians were examined in a field study on over 1000 participants. The hypotheses of (1) lower responsiveness in Japanese pedestrians than in American pedestrians and (2) increased responsiveness as a function of condition were supported in a series of log-linear analyses of pedestrian glances, smiles, nods, and greetings. Both of these main effects were, however, qualified by Culture X Condition interactions on smiles, nods, and greetings, with the large condition effects present in the American pedestrians, but absent in the Japanese pedestrians. The results are discussed in terms of the functions of glances, smiles, nods, and greetings in these brief encounters and how differing cultural norms affect Japanese and American responsiveness. Finally, the limitations of this study and the broader utility of this research paradigm are discussed.

The Sigma-1 receptor (S1R) is known to play a protective role in the central nervous system including the retina. A major barrier for understanding the underlying mechanism is an ambiguity of S1R subcellular localizations. We thus conducted the first electron microscopy (EM) study of S1R subcellular distribution in the mouse retina. Immuno-EM imaging showed previously under-appreciated S1R presence in photoreceptor cells. Unlike in other cell types in previous reports, in photoreceptor cells S1R was found in the nuclear envelope but not localized in the endoplasmic reticulum (ER), raising a possibility of S1R-mediated modulatory mechanisms different than conventionally thought. While in bipolar cells S1R was detected only in the nuclear envelope, in ganglion cells S1R was identified predominantly in the nuclear envelope and found in the ER as well. A predominant localization of S1R in the nuclear envelope in all three retinal neurons implicates a potential role of S1R in modulating nuclear activities. Moreover, its absence in the plasma membrane and presence in the subsurface ER cisternae that are juxtaposed to the plasma membrane in ganglion cells may lend mechanistic insights generally important for frequently reported S1R modulations of ion channels in neurons.

The articles in this special issue provide important, new insight into the evolutionary roots of expressive behavior. Across the three articles, a strong argument is made for behavioral mimicry, expressivity, and laughter providing adaptive value to ancestral humans that is still reflected in our modern world. The place of an evolutionary analysis in the development of a broader functional approach to nonverbal communication is described and discussed. Each article proposes specific dynamics through which expressive behaviors predispose receivers to respond in a manner benefitting the sender. The mediating mechanisms advanced in the articles are examined more closely and modifications in the proposed processes are considered.

This study compared the accuracy and confidence of Japanese and American participants on the Interpersonal Perception Task (IPT-15). The IPT contains 15 brief, real-life scenes on videotape for which there are objectively correct answers about relationships and deception. A total of 344 participants were run in a 2 (Japanese vs. American participants) × 2 (Audiovisual vs. Visual-Only presentation) × 2 (Sex of participant) design. Support was found for the hypothesized greater accuracy of Americans over Japanese, but a Culture × Presentation Modality interaction qualified the main effect of culture. Specifically, Japanese and American participants had virtually identical scores on the IPT-15 in the Visual-Only condition, but Americans' scores increased while Japanese scores decreased in the Audiovisual condition. Analyses of the confidence measures indicated that American participants were much more confident than the Japanese participants, but this difference was larger in the Audiovisual condition than in the Visual-Only condition. In addition, the prediction that women would be more accurate on the IPT, but still report lower confidence than men, was also supported. Finally, Japanese participants with moderate proficiency in spoken English were more accurate on the IPT than those with low English proficiency. The likely processes underlying these differences and the possible directions for future research are discussed.

This study examined the relationship between accuracy and confidence on the Interpersonal Perception Task (IPT-15). This version of the IPT contains 15 brief, real-life scenes on videotape for which there are objectively correct answers to questions about status, intimacy, kinship, competition, and deception. A total of 241 participants were run in a 2 (high vs. low cognitive demand) × 2 (first impression vs. nonverbal cues strategy) × 2 (sex of participant) design. Overall, no significant relationship was found when accuracy scores were correlated with two between-participant measures of confidence. There was, however, a significant relationship within-participants between accuracy and confidence. Thus, participants' rated confidence for each of the 15 scenes did predict accuracy in judgments about the scenes. In addition, a 2 × 2 × 2 ANOVA on participants' transformed accuracy-confidence correlations revealed a small, significant effect of strategy. Specifically, the accuracy-confidence correlations were higher when participants were instructed to attend to specific nonverbal cues in making their judgments than when they were told to rely on their first impressions. Although there were no differences between men and women in either their accuracy or their accuracy-confidence correlations, men rated their confidence significantly higher than did women. The factors affecting the accuracy-confidence relationship and their role in automatic judgments are discussed.

/ In 1990, the United States officially entered the era of pollution prevention with passage of the Pollution Prevention Act. This paper analyzes EPA's implementation of the Pollution Prevention Act from its passage in 1990 to the present. It examines the barriers EPA must overcome if it is to effectively integrate pollution prevention into its existing regulatory structure, including impediments created by statutory and organizational structure, the existing relationship between EPA and the groups it regulates, the fragmented implementation scheme of national environmental regulation, the balancing of conflicting demands advanced by powerful interests, industry's economic and technical concerns, and institutional inertia. It also examines issues such as industry commitment, the limits of prevention, and measurement concerns. The findings suggest that EPA's efforts at shifting to a pollution prevention regulatory ethic that holds primacy over pollution control are mixed. Its organizational structure, statutory authority, and incentives system still reflect a single-medium pollution control focus, appropriations for pollution prevention programs and activities are paltry compared to traditional pollution control programs, and participation in the program is voluntary. Yet, the findings also point to some promising programs that are working to institutionalize a pollution prevention regulatory ethic, and many states appear very committed to the concept.KEY WORDS: Pollution prevention; Source reduction; Pollution control; Alternative regulatory design; Barriers to implementation

The present study examined the effects of cognitive demand and judgment strategy in performance on the Interpersonal Perception Task (Costanzo & Archer, 1989). The Interpersonal Perception Task (IPT) contains 30 brief, real-life scenes on videotape for which there are objectively correct answers to questions about status, intimacy, kinship, competition, and deception. A total of 142 participants were run in a 2 (high vs. low cognitive demand) × 2 (first impression vs. nonverbal cues strategy) × 2 (audiovisual vs. visual only modality) design. A significant Cognitive Demand × Judgment Strategy interaction supported the hypothesized benefit of a first impression strategy when participants experienced high, rather than low, cognitive demand. In contrast, participants receiving the nonverbal cues strategy had higher accuracy under low, rather than high, cognitive demand. The conditional effects of cognitive demand on person perception are considered and the larger role of cognitive resources in interaction is discussed.

The Bodie mining district in Mono County, California, is zoned with a core polymetallic-quartz vein system and silver- and gold-bearing quartz-adularia veins north and south of the core. The veins formed as a result of repeated normal faulting during doming shortly after extrusion of felsic flows and tuffs, and the magmatic-hydrothermal event seems to span at least 2 Ma.

This article develops a parallel processing model of nonverbal communication that emphasizes the interdependence of behavioral and person perception processes from a functional perspective on social interaction. The form and outcome of the behavioral (encoding) and person perception (decoding) processes are a product of three related elements, including: (1) determinants, (2) the social environment, and (3) cognitive-affective mediators. In this model, the determinants (biology, culture, gender, and personality), in combination with the partner and setting, influence interpersonal expectancies, dispositions, goals, affect, and cognitive resources. In turn, these mediators constrain the attention and cognitive effort applied to behavior management and person perception. In general, fewer cognitive resources and decreased effort will have less effect on the outcome of automatic behavioral (e.g., scripts) and person perception (e.g., impressions based on appearance and nonverbal cues) processes than on more demanding ones. The utility of this theory in integrating behavioral and person perception processes into a single system is discussed.

The purpose of the present study was to examine the effect of cognitive demand on interpersonal sensitivity in initial interactions between unacquainted subjects. It was hypothesized that the increased cognitive demand created by initiating an unfavorable (vs. favorable) impression would lead to decreased accuracy in inferences made about an interaction partner. Forty-six pairs of subjects were run in a 2 (favorable or unfavorable impression) × 2 (male dyad or female dyad) factorial design. One member of each subject pair was randomly assigned the perceiver role and given the impression-management instructions. When the interaction was finished, subjects rated themselves and their partner on seven dimensions (e.g., comfortable, friendly, dominant, etc.). Subjects also rated how they thought their partners perceived them on these same dimensions. Two accuracy scores were determined within pairs by correlating: (a) the perceiver’s ratings of the target with the target’s rating of self (direct perspective), and (b) the perceiver’s rating of “my partner thought I felt” with the target’s rating of the perceiver (meta-perspective). The hypothesis was supported in that favorable impression perceivers were significantly more accurate on the meta-perspective judgments than were the unfavorable impression perceivers. In addition, the favorable impression perceivers recalled more descriptive characteristics of the targets than did the unfavorable impression perceivers. The results of the study indicate that a more difficult, impression-management task reduced accuracy in interpersonal perception.

Clozapine plasma levels were monitored in 16 patients during a series of three consecutive treatments (single dose-multiple dose-single dose). Each patient received a single 75-mg dose (3 x 25 mg) with clozapine tablets, and serial plasma samples were collected over 48 hr after the dose. At 48 hr, a multiple-dose regimen was started, consisting of an initial dose escalation period followed by dosing at a constant regimen for at least 6 days. After the last dose, serial plasma samples were again obtained over 72 hr. Drug was then withheld for at least 7 days, a final single 75-mg dose was given, and plasma sampling was repeated. A subset of the patient population (N = 7) was used to test for a food effect during the single-dose treatments. The pharmacokinetic parameters between the initial and the final single dose periods were not significantly different. Similarly, there were no differences within patients when given the dose after fasting (fed 1 hr after dose) or with a meal. In contrast, the terminal elimination rate differed between the single-dose and the multiple-dose treatments (t1/2 m3 = 7.9 hr single dose and 14.2 hr multiple dose) (P less than 0.05) and the dose-normalized area under the plasma concentration/time curves increased 27% with multiple dosing. Since a previous study in patients (Choc et al., Pharm. Res. 4:402-405, 1987) showed dose proportionality of clozapine plasma concentrations during multiple-dose regimens, the present results cannot be described by Michaelis-Menten kinetics.

Q1: Dr. Patterson, your research finds cultural differences in civil (in)attention in one particular context. What does this suggest about the need to consider the role of varied contexts in studying nonverbal behavior within a global context? The long history of research in social psychology clearly emphasizes the importance of situations or contexts in determining social behavior and social judgments. In fact, people from Asian and more collectivistic cultures seem to have a clearer appreciation of the role of situations in shaping behavior, compared to people from Western and more individualistic cultures. This is specifically reflected in Asians showing less of the correspondence bias in making attributions about the behavior of others. That is, Asians are typically less likely to make the automatic dispositional inference (internal attribution) for another person’s behavior and are more likely to make a situational inference (external attribution) than are Westerners. We did not specifically examine different types of contexts, such as the home or work, in studying the subtle behaviors of Japanese and American pedestrians. Thus, we do not have data on cultural differences across contexts. Nevertheless, the minimal responsiveness of Japanese pedestrians as they walked past our confederates was consistent with other research pointing to norms of reserve, caution, and saving face in relating to outgroup individuals. In contrast, this kind of behavioral or expressive restraint may be unnecessary, and even inappropriate, in interactions with other members of one’s own ingroup. Although we do not have direct evidence, it seems likely that comparable contrasting contexts would not have as large an effect on Americans. On a more general level, this suggests that the effects of culture on social behavior may well be qualified by context, that is, culture x context (situation) interactions might be common. Thus, we might find cultural differences in one kind of context, but not in another. As a result we should be cautious in assuming broad cultural differences on the basis of results from a single specific context.

The effects of two intimacy manipulations, 80% eye contact (EC) and combined lean, touch, 50% eye contact (LT), were examined in a bogus waiting period involving a male confederate-male subject pairing. Hypothesized arousal increase was found only for the LT manipulation when it occurred later, rather than earlier, in the waiting period. Associated with that increased arousal were weak tendencies for increased eye contact and talking. These results offered limited support for the arousal model of interpersonal intimacy (Patterson, 1976). However, it also appeared that the directing effect of the specific social context qualified the impact and meaning of the confederate's high intimacy.

This study investigated the effects of touch on compliance to a help request. The experimenter's initiation of touch during the request did increase compliance as measured by time spent scoring bogus personality inventories. The hypothesized role of attraction in mediating the touch-compliance link was not supported. Instead, touch may have served to indicate status or power differences that influenced subjects to comply. A sex of subject × sex of experimenter interaction was manifested in female subjects complying more to female experimenters than did subjects in any other sex pairing.

While much research on nonverbal components of social interaction effectively employs film or videotape recording, a variety of circumstances preclude their use. For those situations that require direct observation of ongoing interactions, a simple technique is proposed that facilitates the reliable judgment of diverse behaviors on a time-sampling basis. This particular technique involves the tape-recorded cuing of exact observation times and instructions, which direct the observer's visual attention to the critical behaviors of specific subjects. The implementation of this technique in one setting and its potential application are briefly discussed.

The purpose of this paper is to offer an elaboration of an earlier classification of functions of nonverbal involvement (Patterson, 1982, 1983). Specifically, two additional functions of nonverbal involvement, the presentational function and the affect-management function are proposed and discussed. The presentational function is manifested in the purposeful involvement patterns with partners that are designed to create an identity or image, either at the individual or dyadic level. The affect-management function is manifested when intense affect produces adjustments in nonverbal involvement that either serves to control the negative affect (fear, shame) or maximizes the positive affect (happiness, joy). The two functions are discussed in terms of the circumstances that contribute to their emergence in social settings.