Seeing to hear better: evidence for early audio-visual interactions in speech identification

Lip reading is the ability to partially understand speech by looking at the speaker's lips. It improves the intelligibility of speech in noise when audio-visual perception is compared with audio-only perception. A recent set of experiments showed that seeing the speaker's lips also enhances sensitivity to acoustic information, decreasing the auditory detection threshold of speech embedded in noise [J. Acoust. Soc. Am. 109 (2001) 2272; J. Acoust. Soc. Am. 108 (2000) 1197]. However, detection is different from comprehension, and it remains to be seen whether improved sensitivity also results in an intelligibility gain in audio-visual speech perception. In this work, we use an original paradigm to show that seeing the speaker's lips enables the listener to hear better and hence to understand better. The audio-visual stimuli used here could not be differentiated by lip reading per se since they contained exactly the same lip gesture matched with different compatible speech sounds. Nevertheless, the noise-masked stimuli were more intelligible in the audio-visual condition than in the audio-only condition due to the contribution of visual information to the extraction of acoustic cues. Replacing the lip gesture by a non-speech visual input with exactly the same time course, providing the same temporal cues for extraction, removed the intelligibility benefit. This early contribution to audio-visual speech identification is discussed in relationships with recent neurophysiological data on audio-visual perception.     

Dynamic analyses of mother-child interactions in functional and dysfunctional dyads: a synergetic approach

Describes the application of a new analytical approach (derived from synergetics, a complex dynamic systems theory) to home observational data of mother–child interactions in average dyads and dyads with children referred for disruptive behavior problems at home and school (n = 11 in each group). Results show that (1) the two groups differed in their daily interactions in predictable ways, and (2) the most frequent patterns of interactions observed in the two groups brought them back repeatedly to behave in similar ways toward each other. The findings are in keeping with a body of literature on mother–child interactions. However, they add to it by providing multivariate, graphical representations of these interactions and by offering a conceptual framework within which to move from an observational to an inferential level of analysis. At that level, the transactional processes that are characteristic of functional and dysfunctional relationships may become apparent.     

Behavioral and pharmacological variables affecting risky choice in rats.

The effects of manipulations of response requirement, intertrial interval (ITI), and psychoactive drugs (ethanol, phencyclidine, and d-amphetamine) on lever choice under concurrent fixed-ratio schedules were investigated in rats. Responding on the "certain' lever produced three 45-mg pellets, whereas responding on the "risky" lever produced either 15 pellets (p = .33) or no pellets (p .67). Rats earned all food during the session, which ended after 12 forced trials and 93 choice trials or 90 min, whichever occurred first. When the response requirement was increased from 1 to 16 and the ITI was 20 s, percentage of risky choice was inversely related to fixed-ratio value. When only a single response was required but the ITI was manipulated between 20 and 120 s (with maximum session duration held constant), percentage of risky choice was directly related to length of the ITI. The effects of the drugs were investigated first at an ITI of 20 s, when risky choice was low for most rats, and then at an ITI of 80 s, when risky choice was higher for most rats. Ethanol usually decreased risky choice. Phencyclidine did not usually affect risky choice when the ITI was 20 s but decreased it in half the rats when the ITI was 80 s. For d-amphetamine, the effects appeared to he related to baseline probability of risky choice; that is, low probabilities were increased and high probabilities were decreased. Although increase in risky choice as a function of the ITI is at variance with previous ITI data, it is consistent with foraging data showing that risk aversion decreases as food availability decreases. The pharmacological manipulations showed that drug effects on risky choice may be influenced by the baseline probability of risky choice, just as drug effects can be a function of baseline response rate.     

Drug discrimination under a concurrent fixed-ratio fixed-ratio schedule.

Pigeons were trained to discriminate 5.0 mg/kg pentobarbital from saline under a two-key concurrent fixed-ratio 10 fixed-ratio 40 schedule of food presentation, in which the fixed-ratio component with the lower response requirement was programmed to reinforce responding on one key after drug administration (pentobarbital-biased key) and on the other key after saline administration (saline-biased key). After responding stabilized, pigeons averaged 98% of their responses on the pentobarbital-biased key during training sessions preceded by pentobarbital, and they averaged 90% of their responses on the saline-biased key during training sessions preceded by saline. In test sessions preceded by doses of pentobarbital, chlordiazepoxide, or ethanol, pigeons switched from responding on the saline-biased key at low doses to responding on the pentobarbital-biased key at higher doses (the dose-response curve was quantal). High doses of phencyclidine produced responding on both keys, whereas pigeons responded almost exclusively on the saline-biased key after all doses of methamphetamine. These and previous experiments using concurrent reinforcement schedules to study drug discrimination illustrate that the schedule of reinforcement is an important determinant of the shape of dose-effect curves in drug-discrimination experiments.     

Infant responses to adult happy and sad vocal and facial expressions during face-to-face interactions

We examined 5-month-olds’ responses to adult facial versus vocal displays of happy and sad expressions during face-to-face social interactions in three experiments. Infants interacted with adults in either happy-sad-happy or happy-happy-happy sequences. Across experiments, either facial expressions were present while presence/absence of vocal expressions was manipulated or visual access to facial expressions was blocked but vocal expressions were present throughout. Both visual attention and infant affect were recorded. Although infants looked more when vocal expressions were present, they smiled significantly more to happy than to sad facial expressions regardless of presence or absence of the voice. In contrast, infants showed no evidence of differential responding to voices when faces were obscured; their smiling and visual attention simply declined over time. These results extend findings from non-social contexts to social interactions and also indicate that infants may require facial expressions to be present to discriminate among adult vocal expressions of affect.     

A novel approach for controlling precipitation kinetics based on diffusional and thermodynamic interactions in multicomponent systems

A novel concept for selection of alloying elements based on diffusional and thermodynamic interactions is proposed. A general model to predict enhancement or reduction of diffusion flux of an element arising from the addition of another is described and specifically applied to determine the appropriate ternary alloying addition to reduce the fast precipitation kinetics observed in binary Ti–Fe based alloy. It is experimentally shown that addition of Cr and Mo decreases the kinetics of precipitation of TiFe, whereas addition of Ta and Nb enhances the kinetics, which is consistent with the predictions of the proposed model.     

The Social Psychology of Black–White Interracial Interactions: Implications for Culturally Competent Clinical Practice

Social psychological research suggests that because of concerns about being perceived in stereotypical ways, people may experience negative affect and diminished attention and cognitive capacity during interracial interactions. The authors discuss this research in relation to therapy and assessment and also offer practical suggestions for ensuring culturally competent professional practice. La investigación en el campo de la psicología social sugiere que, debido a la preocupación por ser percibida de forma estereotipada, la gente puede experimentar sentimientos negativos y un nivel reducido de atención y capacidad cognitiva durante interacciones interraciales. Los autores discuten esta investigación en relación a la terapia y evaluación, y también ofrecen sugerencias prácticas para asegurar una práctica profesional culturalmente competente.     

Concurrent-chains schedules as a method to study choice between alcohol-associated conditioned reinforcers

An extensive body of research using concurrent-chains schedules of reinforcement has shown that choice for one of two differentially valued food-associated stimuli is dependent upon the overall temporal context in which those stimuli are embedded. The present experiments examined whether the concurrent chains procedure was useful for the study of behavior maintained by alcohol and alcohol-associated stimuli. In Experiment 1, rats responded on concurrent-chains schedules with equal variable-interval (VI) 10-s schedules in the initial links. Across conditions, fixed-interval schedules in the terminal links were varied to yield 1∶1, 9∶1, and 1∶9 ratios of alcohol delivery. Initial-link response rates reflected changes in terminal-link schedules, with greater relative responding in the rich terminal link. In Experiment 2, terminal-link schedules remained constant with a 9∶1 ratio of alcohol delivery rates while the length of two equal duration initial-link schedules was varied. Preference for the rich terminal link was less extreme when initial links were longer (i.e., the initial-link effect), as has been previously reported with food reinforcers. This result suggests that the conditioned reinforcing value of an alcohol-associated stimulus depends on the temporal context in which it is embedded. The concurrent-chains procedure and quantitative models of concurrent chains performance may provide a useful framework within which to study how contextual variables modulate preference for drug-associated conditioned reinforcers.     

Predicting counterproductive work behavior from the interaction of personality traits

Much attention has been given to enhancing the prediction of counterproductive work behavior (CWB), with a particular focus on the relationship between the five factor model of personality and CWB. Several scholars have advocated for a more complex view of this relationship, and rather than focusing simply on main effects, to examine the interaction of personality traits in predicting employee behavior. In consideration of the traits most strongly related to CWB, we examined the interaction between: (1) conscientiousness and emotional stability, (2) agreeableness and emotional stability, and (3) conscientiousness and agreeableness on CWB directed at individuals (CWB-I) and the organization (CWB-O). Results from a multi-national sample illustrate the interaction of traits increases the prediction of CWB over and above a single trait approach. The interactions suggest employees perform the least CWB when they are high on both traits (in the respective trait pairings), but low levels on either trait relate to increased CWB, and at levels comparable to individuals low on both traits. We conclude research on personality and CWB would benefit from an interactive approach as it allows for greater prediction of CWB-O and CWB-I, which is important in light of the organizational and interpersonal consequences of employee misbehavior.