Hemispheric asymmetries in auditory distraction

Serial-verbal short-term memory is impaired by irrelevant sound, particularly when the sound changes acoustically (the changing-state effect). In contrast, short-term recall of semantic information is impaired only by the semanticity of irrelevant speech, particularly when it is semantically related to the target memory items (the between-sequence semantic similarity effect). Previous research indicates that the changing-state effect is larger when the sound is presented to the left ear in comparison to the right ear, the left ear disadvantage. In this paper, we report a novel finding whereby the between-sequence semantic similarity effect is larger when the irrelevant speech is presented to the right ear in comparison to the left ear, but this right ear disadvantage is found only when meaning is the basis of recall (Experiments 1 and 3), not when order is the basis of recall (Experiment 2). Our results complement previous research on hemispheric asymmetry effects in cross-modal auditory distraction by demonstrating a role for the left hemisphere in semantic auditory distraction.     

The cognitive neuroscience of auditory distraction

We are often aware of the content of distracting sound, although typically remain unaware of the processes by which that sound is disruptive. Disruption can occur even when the sound is ignored and unrelated to the task being performed. In a recent major development, Gisselg?rd et al. have used positron emission tomography to reveal how distracting sounds recruit the involvement of dorsolateral prefrontal cortex.     

Reduction in auditory distraction by retrieval strategy

Most research on auditory distraction on task performance focuses on those features of the sound that determine a drop in efficiency, with scant regard for examining the processing properties inherent in the focal task. We report how one such property, retrieval strategy, can also influence the degree of disruption by background sound. Using a task that called for the retrieval of realistic train journey information, we showed that retrieval by categories of verbal sequences was not susceptible to disruption by office sound - 65-75 dB(A). However, versions of the task requiring either free or serial recall showed evidence of disruption, a pattern of results consistent with the changing-state account of the irrelevant sound effect, which highlights the key role of serial rehearsal in determining disruption.     

Nonconcurrently presented auditory tones reduce distraction

Recent research has demonstrated that task-irrelevant stimuli presented simultaneously with a target-distractor stimulus reduce distraction and improve selective attention. In studies examining this reduced interference effect, visual selective attention tasks and concurrently presented task-irrelevant stimuli are used. We report first evidence for a similar effect in the auditory domain and with nonconcurrent stimuli (i.e., the task-irrelevant stimuli are presented before the target). The effect of nonconcurrently presented auditory tones on an auditory Stroop task developed by Leboe and Mondor (Psychological Research, 71, 568--575, 2007) was investigated. Stroop interference was reduced when task-irrelevant tones were presented before the Stroop stimulus. We conclude that task-irrelevant stimuli can improve selective attention not only when presented concurrently, but also when presented before the selective attention task. Our results are consistent with the hypothesis that interference reduction is due to perceptual dilution caused by task-irrelevant stimuli.     

Invalid cues impair auditory motion sensitivity

Compelling lateral motion can be experienced when intensity differences between the two cars change over time. Whether our sensitivity to this dynamic interaural stimulation could be influenced by directional cues was the focus of the present study. On each trial, amplitude-modulated pure tones were presented either diotically (no-motion condition) or dichotically (motion condition), and participants indicated whether lateral motion was present or absent. Randomly across trials, the stimuli were preceded by a valid directional cue, an invalid directional cue, or no cue, while the motion to be detected was identical across these cue conditions. The data indicate that motion sensitivity was comparable in the valid-cue and no-cue conditions. Relative to each of those conditions, however, motion sensitivity was significantly lower in the invalid-cue condition, and motion was reported significantly less often. The results provide evidence that our sensitivity to dynamic interaural intensity differences can be significantly affected by a non-sensory factor, namely cue validity.     

Happiness increases distraction by auditory deviant stimuli

Rare and unexpected changes (deviants) in an otherwise repeated stream of task‐irrelevant auditory distractors (standards) capture attention and impair behavioural performance in an ongoing visual task. Recent evidence indicates that this effect is increased by sadness in a task involving neutral stimuli. We tested the hypothesis that such effect may not be limited to negative emotions but reflect a general depletion of attentional resources by examining whether a positive emotion (happiness) would increase deviance distraction too. Prior to performing an auditory‐visual oddball task, happiness or a neutral mood was induced in participants by means of the exposure to music and the recollection of an autobiographical event. Results from the oddball task showed significantly larger deviance distraction following the induction of happiness. Interestingly, the small amount of distraction typically observed on the standard trial following a deviant trial (post‐deviance distraction) was not increased by happiness. We speculate that happiness might interfere with the disengagement of attention from the deviant sound back towards the target stimulus (through the depletion of cognitive resources and/or mind wandering) but help subsequent cognitive control to recover from distraction.     

Location and frequency cues in auditory selective attention

The roles of frequency and location cues in auditory selective attention were investigated in a series of experiments in which target tones were distinguished from distractors by frequency, location, or the conjunction of frequency and location features. When frequency separations in high-rate tone sequences were greater than 1 octave, participants were fastest at identifying targets defined by frequency and were sometimes faster at identifying conjunction than location targets. Frequency salience diminished as filtering demands were reduced: At long interstimulus intervals (> 2.0 s), performance was superior in location conditions. The results suggest that frequency may play a role in auditory selective attention tasks analogous to the role of spatial position in visual attention.     

Neuronal effects of auditory distraction on visual attention

Selective attention in the presence of distraction is a key aspect of healthy cognition. The underlying neurobiological processes, have not, however, been functionally well characterized. In the present study, we used functional magnetic resonance imaging to determine how ecologically relevant distracting noise affects cortical activity in 27 healthy adults during two versions of the visual Sustained Attention To Response Task (SART) that differ in difficulty (and thus attentional load). A significant condition (noise or silence) by task (easy or difficult) interaction was observed in several areas, including dorsolateral prefrontal cortex (DLPFC), fusiform gyrus (FG), posterior cingulate (PCC), and pre-supplementary motor area (PreSMA). Post hoc analyses of interaction effects revealed deactivation of DLPFC, PCC, and PreSMA during distracting noise under conditions of low attentional load, and activation of FG and PCC during distracting noise under conditions of high attentional load. These results suggest that distracting noise may help alert subjects to task goals and reduce demands on cortical resources during tasks of low difficulty and attentional load. Under conditions of higher load, however, additional cognitive resources may be required in the presence of noise.     

Sources of auditory masking in infants: distraction effects.

Previous work has demonstrated that infants' thresholds for a pure tone are elevated by a masker more than would be predicted from their critical bandwidths. The present studies explored the nature of this additional masking. In Experiment 1, detection thresholds of 6-month-old infants and of adults for a 1-kHz tone were estimated under three conditions: in quiet, in the presence of a 4- to 10-kHz bandpass noise at 40 dB SPL, and in the presence of the same noise at 50 dB SPL. The noise was gated on at the beginning of each trial. Adult thresholds were the same in all three conditions, indicating that little or no sensory masking took place in the presence of the noise. Infant thresholds were about 10 dB higher in the presence of the noise. We term this effect distraction masking. In Experiment 2, the effect of gating the noise on at trial onset was examined. Thresholds for the same tone were estimated in quiet and in the presence of the band-pass noise at 40 dB SPL, but the noise was presented continuously during the session. Under these conditions, distraction masking was still observed for infants. These findings suggest that a masker can have nonsensory effects on infants' performance in a psychoacoustic task.     

Relational and absolute cues in auditory discrimination by monkeys

Rhesus monkeys were trained to make auditory frequency, intensity, and duration discriminations. Initial training was carried out with a procedure which allowed the utilization of either relational cues or absolute cues. Later tests with similar auditory parameters allowed only the utilization of relational cues. Performance on these latter tests indicated that relational rather than absolute cues had been utilized when both types were available on the frequency and intensity discrimination tasks. However, absolute rather than relational cues were apparently utilized in making duration discriminations.     

Influence of correlated visual cues on auditory signal detection

Two experiments investigated the effects on auditory signal detection of introducing visual cues that were partially correlated with the signal events. The results were analyzed in terms of a detection model that assumes that such cue-signal correlations will not affect sensitivity, but will instead cause the subject to develop separate response biases for each cue. The model specifies a functional relationship between the asymptotic values of these cuecontingent biases. The overall results of the experiments supported the detection assumptions of the model and the general bias learning assumption, but indicated a more complex learning process than that specified by the model.     

The impact of auditory distraction on retrieval of visual memories

Recent research has revealed that the presence of irrelevant visual information during retrieval of long-term memories diminishes recollection of task-relevant visual details. Here, we explored the impact of irrelevant auditory information on remembering task-relevant visual details by probing recall of the same previously viewed images while participants were in complete silence, exposed to white noise, or exposed to ambient sounds recorded at a busy café. The presence of auditory distraction diminished objective recollection of goal-relevant details, relative to the silence and white noise conditions. Critically, a comparison with results from a previous study using visual distractors showed equivalent effects for auditory and visual distraction. These findings suggest that disruption of recollection by external stimuli is a domain-general phenomenon produced by interference between resource-limited, top-down mechanisms that guide the selection of mnemonic details and control processes that mediate our interactions with external distractors.     

The effects of marker-related temporal cues on auditory gap-duration discrimination

In three experiments, we examined the ability of listeners to discriminate the duration of temporal gaps (silent intervals) and the influence of other temporal stimulus properties on their performance. In the first experiment, gap-duration discrimination thresholds were measured either in continuous noise or with noise markers with durations of 3 and 300 ms. Thresholds measured with 300-ms markers differed from those measured in continuous noise or with 3-ms markers. In the second experiment, stimuli consisting of a gap between two discrete markers were generated such that the gap duration, the onset-to-onset duration between markers, and the duration of the first marker were pseudorandomized across trials. Listeners’ responses generally were consistent with the cue that was identified as the target cue from among the three cues in each block of trials, but the data suggested that the onset-to-onset cue was particularly salient in all conditions. Using a modified method-of-adjustment procedure in the third experiment, subjects were instructed to discriminate between the durations of gaps in discrete markers of different durations in two intervals, where the gap duration in one interval was adapted to measure the point of subjective equality. Without feedback, listeners tended to equate the onset-to-onset times of the markers rather than the gap durations. Overall, the results indicated that listeners’ judgments of silent gaps between two discrete markers are strongly influenced by the onset-to-onset time, or rhythm, of the markers.     

Looking where you listen: visual cues and auditory attention

In the non-laboratory environment, we are generally able to see the source of the sounds to which we are attending. In a preliminary examination of how and to what degree we might use this visual information, subjects shadowed one of two female voices when able to see the persons speaking (Experiment I) or when able to see, and thus precisely localize, the auditory loudspeakers (Experiment II). Selective performance was improved by being able to see the lip movements of the people whose voices were heard, and by being able to localize visually the sources of the voices.