Division of attention between simultaneous and successive nonverbal signals varying in discriminability

Impaired performance indexed by accuracy usually accompanies the division of attention between simultaneous difficult signals. Presenting the signals successively reduces the impairment. Presenting easy signals eliminates it. Both variables crucial to these findings, relative time of onset and discriminability, were manipulated in the first experiment using a two-choice recognition paradigm involving bimodal signals. The results showed that, when a difficult signal was followed by two simultaneous easy ones, in a different modality from the first, performance was significantly worse on each than on the same signals presented alone. Simultaneous presentation of all three signals further increased the impairment for the difficult signal, but not for the easy ones. In the second experiment, the discriminability of the following signals was varied. The results showed, that when a difficult signal was followed by either two simultaneous easy signals, in a different modality from the first, or by two difficult ones, performance was significantly worse than on the same difficult signal presented alone. Further, when the preceding difficult signal was auditory, but not when it was visual, performance was better with easy following signals than with difficult ones. It is argued that an adequate account of the results from the two experiments requires the following assumptions concerning the processing of multiple signals: (1) a loss associated both with the acquisition and the storage of information, (2) preferential processing of visual signals over auditory ones. Proposals are made for the incorporation of both assumptions into a single model of divided attention.     

Divided attention between simultaneous auditory and visual signals

Past studies of simultaneous attention to pairs of visual stimuli have used the “dual-task” paradigm to show that identification of the direction of a change in luminance, whether incremental or decremental, is “capacity-limited,” while simple detection of these changes is governed by “capacity-free” processes. On the basis of that finding, it has been suggested that the contrast between identification and detection reflects different processes in the sensory periphery, namely the responses of magno- and parvocellular receptors. The present study questions that assertion and investigates the contribution of central processing in resource limitation by applying the dual task to a situation in which one stimulus is auditory and one is visual. The results are much the same as before, with identification demonstrating the tradeoff in performance generally attributed to a limited capacity but detection showing no loss compared with single-task controls. This implies that limitations on resources operate at a central level of processing rather than in the auditory and visual peripheries.     

Contextual cueing of visual attention

Visual context information constrains what to expect and where to look, facilitating search for and recognition of objects embedded in complex displays. This article reviews a new paradigm called contextual cueing, which presents well-defined, novel visual contexts and aims to understand how contextual information is learned and how it guides the deployment of visual attention. In addition, the contextual cueing task is well suited to the study of the neural substrate of contextual learning. For example, amnesic patients with hippocampal damage are impaired in their learning of novel contextual information, even though learning in the contextual cueing task does not appear to rely on conscious retrieval of contextual memory traces. We argue that contextual information is important because it embodies invariant properties of the visual environment such as stable spatial layout information as well as object covariation information. Sensitivity to these statistical regularities allows us to interact more effectively with the visual world.     

Nonverbal signals speak up: Association between perceptual nonverbal dominance and emotional intelligence

Emotional communication uses verbal and nonverbal means. In case of conflicting signals, nonverbal information is assumed to have a stronger impact. It is unclear, however, whether perceptual nonverbal dominance varies between individuals and whether it is linked to emotional intelligence. Using audiovisual stimulus material comprising verbal and nonverbal emotional cues that were varied independently, perceptual nonverbal dominance profiles and their relations to emotional intelligence were examined. Nonverbal dominance was found in every participant, ranging from 55 to 100%. Moreover, emotional intelligence, particularly the ability to understand emotions, correlated positively with nonverbal dominance. Furthermore, higher overall emotional intelligence as well as a higher ability to understand emotions were linked to smaller reaction time differences between emotionally incongruent and congruent stimuli. The association between perceptual nonverbal dominance and emotional intelligence, and more specifically the ability to understand emotions, might reflect an adaptive process driven by the experience of higher authenticity in nonverbal cues.     

Age effects on a nonverbal auditory sustained attention task

A nonverbal auditory test of sustained attention was administered to 20 young and 20 elderly women, screened to ensure good health. Groups were matched for intelligence. Older subjects performed as accurately as younger subjects. Neither group showed increases in response latency as a function of time spent on test. Older subjects took longer to respond than younger subjects, but only for a particular combination of stimulus duration and order of presenting stimulus durations. When subjects were presented long tones first, there was no difference in response latency associated with age or stimulus duration. When short tones were presented first, older subjects were slower than younger subjects in both duration conditions and in response to long tones were slower than all other subjects.     

Distractor eccentricity and its effect on selective attention

Previous research has shown conflicting results regarding the effect of distractor eccentricity on selective attention. The present study examines the relationship between a distractor's retinal location and participants' response latencies to a target while holding constant the distribution of attention. In three experiments, the participants searched for a target among several distractors. The retinal location of the critical distractor was manipulated so that it was at either a central or a peripheral location. The results show that all else being equal, an incompatible distractor causes more interference at a peripheral location than at a central location. This distractor eccentricity effect suggests that the visual system can overcome the default bias in the distribution of attention that favors a central stimulus.     

Mixed signals: The effect of conflicting reward- and goal-driven biases on selective attention

Attentional selection depends on the interaction between exogenous (stimulus-driven), endogenous (goal-driven), and selection history (experience-driven) factors. While endogenous and exogenous biases have been widely investigated, less is known about their interplay with value-driven attention. The present study investigated the interaction between reward-history and goal-driven biases on perceptual sensitivity (d’) and response time (RT) in a modified cueing paradigm presenting two coloured cues, followed by sinusoidal gratings. Participants responded to the orientation of one of these gratings. In Experiment 1, one cue signalled reward availability but was otherwise task irrelevant. In Experiment 2, the same cue signalled reward, and indicated the target’s most likely location at the opposite side of the display. This design introduced a conflict between reward-driven biases attracting attention and goal-driven biases directing it away. Attentional effects were examined comparing trials in which cue and target appeared at the same versus opposite locations. Two interstimulus interval (ISI) levels were used to probe the time course of attentional effects. Experiment 1 showed performance benefits at the location of the reward-signalling cue and costs at the opposite for both ISIs, indicating value-driven capture. Experiment 2 showed performance benefits only for the long ISI when the target was at the opposite to the reward-associated cue. At the short ISI, only performance costs were observed. These results reveal the time course of these biases, indicating that reward-driven effects influence attention early but can be overcome later by goal-driven control. This suggests that reward-driven biases are integrated as attentional priorities, just as exogenous and endogenous factors.     

Retinal location and its effect on the spatial distribution of visual attention

A series of studies tested for distractor compatibility effects across wide target/distractor distances (0.6 degree to 20 degrees of visual angle). The effects of precue condition, constant/varied target location, horizontal/vertical distractor distance, and foveal/peripheral presentation were studied. Results show strong compatibility effects across wide distances when distractors are at peripheral retinal locations. When both stimuli were presented at the same peripheral location in opposite hemifields, compatibility effects were evident within an area of at least 2.5 degrees of visual angle. In contrast, when foveally placed distractors were used, compatibility effects were found primarily with target letters positioned near. The findings suggest that distance effects are not homogeneous across retinal location.     

Contextual influences on the sequential congruency effect

The sequential congruency effect (SCE) refers to the reduction in the size of the congruency effect following incongruent, relative to congruent, trials. Prior evidence indicated that the SCE does not generalize across tasks or different conflict-producing feature dimensions. We present results from a Stroop task showing that when the local list context is such that all colors and words appear in the same proportion of congruent trials, the SCE is present, but when those same items vary in the proportions congruent, the SCE is absent. We suggest that if stimuli are sufficiently consistent in the informativeness of their dimensions for the responses, individuals will attempt to track such information and weight the dimensions accordingly. In this way, the SCE reflects sequential adjustments to the weights given to individual stimulus dimensions in an attempt to track this information.     

Selective strategies in the assimilation of successively presented signals

It is found that performance in experiments on the psychological refractory period is highly affected by instructions. In the present experiment subjects were instructed either to handle the signals successively or to group them. Both instructions were obeyed. This seems to indicate that the human organism has various strategies available. Which strategy is actually applied is likely to depend on the structure of the experimental situation, and partly also, on momentary preference. This may explain the variety of results in the literature on this subject.

Finally, it is found that, when two signals are presented simultaneously, the total reaction time is considerably shorter if the signals are “grouped” than if they are “handled successively.” This difference disappears at interstimulus intervals of 0.2 sec. and 0.4 sec. The hypothesis is put forward, that the gain in time at the former case is due to simultaneous perceptual processing of the signals.     

Digital chameleons: automatic assimilation of nonverbal gestures in immersive virtual environments

Previous research demonstrated social influence resulting from mimicry (the chameleon effect); a confederate who mimicked participants was more highly regarded than a confederate who did not, despite the fact that participants did not explicitly notice the mimicry. In the current study, participants interacted with an embodied artificial intelligence agent in immersive virtual reality. The agent either mimicked a participant's head movements at a 4-s delay or utilized prerecorded movements of another participant as it verbally presented an argument. Mimicking agents were more persuasive and received more positive trait ratings than nonmimickers, despite participants' inability to explicitly detect the mimicry. These data are uniquely powerful because they demonstrate the ability to use automatic, indiscriminate mimicking (i.e., a computer algorithm blindly applied to all movements) to gain social influence. Furthermore, this is the first study to demonstrate social influence effects with a nonhuman, nonverbal mimicker.     

Status signals: Adaptive benefits of displaying and observing the nonverbal expressions of pride and shame

A growing body of research suggests that pride and shame are associated with distinct, cross-culturally recognised nonverbal expressions, which are spontaneously displayed in situations of success and failure, respectively. Here, we review these findings, then offer a theoretical account of the adaptive benefits of these displays. We argue that both pride and shame expressions function as social signals that benefit both observers and expressers. Specifically, pride displays function to signal high status, which benefits displayers by according them deference from others, and benefits observers by affording them valuable information about social-learning opportunities. Shame displays function to appease others after a social transgression, which benefits displayers by allowing them to avoid punishment and negative appraisals, and observers by easing their identification of committed group members and followers.     

Status signals: adaptive benefits of displaying and observing the nonverbal expressions of pride and shame

A growing body of research suggests that pride and shame are associated with distinct, cross-culturally recognised nonverbal expressions, which are spontaneously displayed in situations of success and failure, respectively. Here, we review these findings, then offer a theoretical account of the adaptive benefits of these displays. We argue that both pride and shame expressions function as social signals that benefit both observers and expressers. Specifically, pride displays function to signal high status, which benefits displayers by according them deference from others, and benefits observers by affording them valuable information about social-learning opportunities. Shame displays function to appease others after a social transgression, which benefits displayers by allowing them to avoid punishment and negative appraisals, and observers by easing their identification of committed group members and followers.     

Effects of cross-modal and intramodal division of attention on perceptual implicit memory

Extant results motivate 3 hypotheses on the role of attention in perceptual implicit memory. The first proposes that only intramodal manipulations of attention reduce perceptual priming. The second attributes reduced priming to the effects of distractor selection operating in a central bottleneck process. The third proposes that manipulations of attention only affect priming via disrupted stimulus identification. In Experiment 1, a standard cross-modal manipulation did not disrupt priming in perceptual identification. However, when study words and distractors were presented synchronously, cross-modal and intramodal distraction reduced priming. Increasing response frequency in the distractor task produced effects of attention regardless of target-distractor synchrony. These effects generalized to a different category of distractors arguing against domain-specific interference. The results support the distractor-selection hypothesis.     

Contextual interference effect on acquisition and retention of pistol-shooting skills

The effects of contextual interference on learning pistol-shooting skills in a natural training environment were examined. The shooting skills consisted of three "stages" with different requirements for the skill variations commonly used in the field. 12 participants were randomly assigned into one of two practice conditions, blocked vs serial. Following a 20-min. safety and skill instructional session, Blocked group practiced 10 trials in a row at each stage, while Serial group performed 5 trials in a row for each of the three stages and then repeated the cycle. Both groups completed a total of 30 practice trials over the three stages. A 10-min. rest interval was provided prior to a retention test which included 9 trials (3 trials at each stage in a blocked format). Results based on the data of Stage III, the most complex skill among the three stages, showed a pattern consistent with previous findings that practicing in the serial schedule depressed performance during initial training but maintained the performance better at retention, relative to the blocked practice.     

Influence of verbal and nonverbal references to print on preschoolers' visual attention to print during storybook reading

How much do preschool children look at print within storybooks when adults read to them? This study sought to answer this question as well as to examine the effects of adult verbal and nonverbal references to print on children's visual attention to print during storybook reading. Forty-four preschool-aged children participated in this study designed to determine the amount of visual attention children paid to print in 4 planned variations of storybook reading. Children's visual attention to print was examined when adults commented and questioned about print (verbal print condition) or pointed to and tracked the print (nonverbal print condition), relative to 2 comparison conditions (verbatim reading and verbal picture conditions). Results showed that children rarely look at print, with about 5%-6% of their fixations allocated to print in verbatim and verbal picture reading conditions. However, preschoolers' visual attention to print increases significantly when adults verbally and nonverbally reference print; both reading styles exerted similar effects. The authors conclude that explicit referencing of print is 1 way to increase young children's contacts with print during shared storybook reading.