Overriding auditory attentional capture

Attentional capture by color singletons during shape search can be eliminated when the target is not a feature singleton (Bacon & Egeth, 1994). This suggests that a "singleton detection" search strategy must be adopted for attentional capture to occur. Here we find similar effects on auditory attentional capture. Irrelevant high-intensity singletons interfered with an auditory search task when the target itself was also a feature singleton. However, singleton interference was eliminated when the target was not a singleton (i.e., when nontargets were made heterogeneous, or when more than one target sound was presented). These results suggest that auditory attentional capture depends on the observer's attentional set, as does visual attentional capture. The suggestion that hearing might act as an early warning system that would always be tuned to unexpected unique stimuli must therefore be modified to accommodate these strategy-dependent capture effects.     

An examination of attentional control in the auditory modality: Further evidence for auditory orienting

Four experiments are reported that examine attentional control in the auditory modality. In Experiment 1, the subjects made detection responses to the onset of a monaurally presented pure tone that was preceded by a pure-tone cue. On a valid trial, the cue was presented in the same ear as the target; on an invalid trial, it was presented in the contralateral ear to the target; and on a neutral trial, it was presented in both ears. Overall performance was facilitated on valid trials in comparison with invalid trials. In later experiments, the subjects made choice decisions about the location of the target, and significant cuing effects were found relative to the neutral condition. Finally, performance was assessed in the presence of central (spoken) word cues. Here, the content of the cue specified the likely location of the target. Under these conditions, costs and benefits were found over a range of cue-target stimulus onset asynchronies. The results are discussed in terms of automatic and controlled attentional processes.     

Object-based attentional selection and aging

The authors conducted 2 studies to examine potential age-related differences in object-based attentional selection. Participants were briefly presented with pairs of wrenches and were asked to make 1 response if both target properties (i.e., an open end and a hexagonal end) were present and another response if only a single target property was present in the display. The critical manipulation was whether the target properties were present on 1 wrench or distributed between 2 wrenches. Space-based models of selective attention predict no difference in performance between these conditions. However, object-based attentional selection models predict better performance when both target properties appear on a single object. The results from both of the studies were consistent with object-based models of attentional selection. Furthermore, both young and old adults showed similar performance effects, suggesting the object-based attentional selection is insensitive to normal aging.     

Distraction and the auditory attentional blink

When two target stimuli (T1 and T2) are presented in close succession within a stimulus sequence, detection or discrimination performance for T2 is often impaired; this phenomenon is called the attentional blink (AB). Growing evidence suggests that the AB is present not only for visual, but also for auditory stimuli. Because sounds have a strong potential to attract attention when they are presented after longer silent intervals or in a sequence from which they stand out because of their rare or novel physical features, it seems possible that the involuntary and excessive allocation of attention to T1 (distraction) may contribute to the AB. By varying the saliency of T1, we showed that distraction does contribute to the auditory AB effect, but the contribution is short-lived: Only stimuli immediately following T1 are affected.     

Human gaze control during real-world scene perception

In human vision, acuity and color sensitivity are best at the point of fixation, and the visual-cognitive system exploits this fact by actively controlling gaze to direct fixation towards important and informative scene regions in real time as needed. How gaze control operates over complex real-world scenes has recently become of central concern in several core cognitive science disciplines including cognitive psychology, visual neuroscience, and machine vision. This article reviews current approaches and empirical findings in human gaze control during real-world scene perception.     

Effects of attentional focusing on pain perception

Two experiments were conducted to examine the hypothesized differential effectiveness of two attentional focusing strategies in pain perception. In the first experiment, subjects (72 male college students) rated their levels of pain after being exposed to either low- or high-intensity pressure stimulation for 75 s. Subjects were instructed to use either an external or internal focus of attention during the pain induction. Results revealed that external focusing was more effective for coping than internal focusing across both levels of stimulus intensity. The second experiment was a replication of the first, and featured bolstered internal focusing and stimulus intensity manipulations. Results showed that high-intensity stimulation produced higher pain ratings than did low-intensity stimulation for subjects in the internal focusing conditions, but not for those in the external focusing conditions. The findings support the power of distraction strategies for dealing with short-term pain with a rapid onset. Theoretical implications are discussed.The authors thank Darwyn E. Linder and Daniel M. Landers for their help in development of this research. The authors are also indebted to Sarah Colley, Jona Davis, Nanci Neuberger, and Rebecca Roberts for their assistance in data collection.     

Automatic and attentional components in perception of shape-at-a-slant

In perceiving shape-at-a-slant it is assumed that a sequence of operations is executed. The aim of these experiments was to determine the extent to which execution of these operations requires allocation of attention. Three hypotheses were considered: zero automaticity--that all of the operations require attention; partial automaticity--that the operations culminating in a representation of projective shape and slant-in-depth are automatic while the combinatorial operations culminating in a distally correlated shape require attention; full automaticity--that the entire sequence of operations is automatic, proceeding without allocation of attention. To decide among these hypotheses, subjects performed forced-choice shape recognition tests under two conditions: In the shape-directed condition subjects were motivated to process shape. In the numerosity-directed condition subjects were motivated to direct attention to discrimination of numerosity, thereby causing attention to be diverted from processing of shape. Examination of the pattern of choices on the recognition test showed results that conformed best to the hypothesis of partial automaticity.     

Object file continuity and the auditory attentional blink

Three experiments were designed to investigate the causes of the auditory attentional blink (AB). Experiments 1A and 1B revealed that there was a larger auditory AB when the target and the distractors were different in two attributes than when they were different in only one attribute. Experiments 2A and 2B showed that for pure-tone distractor sequences, there were small auditory AB deficits when both the target and the probe were different from the distractors in two attributes or in one attribute; however, for pulse distractor sequences, there was a large auditory AB when both the target and the probe were different from the distractors in one attribute, but not when they were different in two attributes. Experiments 3A and 3B revealed that regardless of the relationship of the target to the subsequent distractors, a large AB was generated if it was the first sound in a sequence. Moreover, only a very small AB was apparent when the distractors following the probe were replaced by silence. These results indicated that the auditory AB is affected by both the requirement of creating and consolidating a new object file for the target and the overwriting of the probe by the distractors following it.     

Action for perception: a motor-visual attentional effect

Five experiments investigated whether preparation of a grasping movement affects detection and discrimination of visual stimuli. Normal human participants were required to prepare to grasp a bar and then to grasp it as fast as possible on presentation of a visual stimulus. On the basis of the degree of sharing of their intrinsic properties with those of the to-be-grasped bar, visual stimuli were categorized as "congruent" or "incongruent." Results showed that grasping reaction times to congruent visual stimuli were faster than reaction times to incongruent ones. These data indicate that preparation to act on an object produces faster processing of stimuli congruent with that object. The same facilitation was present also when, after the preparation of hand grasping, participants were suddenly instructed to inhibit the prepared grasping movement and to respond with a different motor effector. The authors suggest that these findings could represent an extension of the premotor theory of attention, from orienting of attention to spatial locations to orienting of attention to graspable objects.     

Two types of auditory sequence perception

It has been suggested recently that there are two fundamentally distinct types of auditory sequence perception in man: (1) hofistic pattern recognition (HPR), operating for component item durations from a few milliseconds up to about 200 msec; and (2) direct identification of components and their order (Direct ICO), requiring verbal encoding of names for constituent sounds and requiring item durations roughly 200 msec and above for extended sequences. The present study, using only the very first judgments from 795 untrained participants presented with recycled three-item sequences, provided data consistent with this dichotomous formulation. In addition, it appeared that separate bursts of a noise band generated on-line were treated as different components in HPR and could not be used for sequence matching; “frozen” noise bursts having identical microstructure were treated as the same component and permitted HPR. On-fine noise bursts permitted Direct ICO, with naming based on long-term spectral characteristics of noise.     

Effect of distractor sounds on the auditory attentional blink

Four experiments were conducted to determine whether or not the presence and placement of distractors in a rapid serial auditory stream has any influence on the emergence of the auditory attentional blink (AB). Experiment 1 revealed that the presence of distractors is necessary to produce the auditory AB. In Experiments 2 and 3, the auditory AB was reduced when the distractor immediately following the probe was replaced by silence but not when the distractor following the target was replaced by silence. Finally, in Experiment 4, only a very small auditory AB was found to remain when all distractors following the probe were replaced by silence. These results suggest that the auditory AB is affected both by the overwriting of the probe by the distractors following it and by a reduction in discriminability generated by all of the distractors presented in the sequence.     

Infants' perception of multiple-group auditory patterns

Six- and 12-month-old infants were tested for their perception of a variety of features of multiple-group auditory patterns. Each pattern comprised nine pure tones organized as three groupings each of three elements. The features examined included: (1) features having to do with frequency composition, designated as “local” pattern features; and (2) features involving relations between pattern components, designated as “global” pattern features. Infants were tested with a Go/No-Go conditioned head-turn procedure. Twelve-month-olds readily performed all discriminations. By contrast, 6-month-olds had greater difficulty discriminating local than global pattern features and showed limitations in their ability to organize three distinct groupings of elements into a unified pattern. Results are discussed with reference to infants' perception of features of single-group patterns and the notion of developmental changes in auditory information-processing capacities.     

Attentional and perceptual sources of the auditory attentional blink

When a rapid succession of auditory stimuli is listened to, processing of the second of two successive targets among fillers is often impaired, a phenomenon known as the attentional blink (AB). Three experiments were conducted to examine the role of filler items in modulating the size of the auditory AB, using a two-alternative forced choice discrimination paradigm. In the first experiment, dual-stream presentations in which low- and high-pitch items were separated by six semitones were tested. A transient deficit in reporting the probe was observed in the presence of fillers that was greater when fillers were in the same stream as the probe. In the absence of a filler, there was a residual deficit, but this was not related to the time lag between the target and the probe. In the second and third experiments, in which single-stream presentations were used, a typical AB was found in the presence of homogeneous fillers, but heterogeneous fillers tended to produce a greater deficit. In the absence of a filler, there was little or no evidence of a blink. The pattern of results suggests that other attentional and perceptual factors contribute to the blink.     

Ageing and attentional control

The research examines the structural bottleneck account and the resource account of the substantial dual-task deficits among older adults. Procedures from two common dual-task methodologies—the psychological refractory period and the relative-priority manipulation—were used to encourage maximization of the joint performance. Performance and time-sharing strategies from subjects between the ages of 20 and 70 years were examined. Age-related declines in time-sharing efficiency and in the precision of the executive control process were observed. The age-related effect was larger when two manual responses were required than when one manual and one vocal response were required, but no evidence for obligatory sequential processing was found. Except for the most demanding conditions, comparable practice effects were observed between the younger and older subjects, suggesting considerable cognitive plasticity in the older subjects. Implications for the two attentional accounts were discussed.