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Keeping task-relevant sensory events in the focus of attention while ignoring irrelevant ones is crucial for optimizing task behavior. This attention-distraction balance might change with the perceptual demands of the ongoing task: while easy tasks might be performed with low attentional effort, difficult ones require enhanced attention. The goal of the present study was to investigate how task difficulty affected allocation of attention and distractibility in an auditory distraction paradigm. Participants performed a tone duration discrimination task in which tones were rarely, occasionally presented at a rare pitch (distracters), and task difficulty was manipulated by the duration difference between short and long tones. Short tones were consistently 200 ms long, while long tone duration was 400 ms in the easy, and 260 ms in the difficult condition. Behavioral results and deviant-minus-standard event-related potential (ERP) waveforms suggested similar magnitudes of distraction in both conditions. ERPs without such a subtraction showed that tone onsets were preceded by a negative-going trend, suggesting that participants prepared for tone onsets. In the difficult condition, N1 amplitudes to tone onsets were enhanced, indicating that participants invested more attentional resources. Increased difficulty also slowed down tone offset processing as reflected by significantly delayed offset-related P1 and N1/N2 waveforms. These results suggest that although task difficulty compels participants to attend the tones more strongly, this does not have significant impact on distraction-related processing., (Copyright © 2019 The Authors. Published by Elsevier B.V. All rights reserved.)

The present study investigated how fast younger and older adults recovered from a distracted attentional state induced by rare, unpredictable sound events. The attentional state was characterized by the auditory N1 event-related potential (ERP), which is enhanced for sound events in the focus of attention. Younger (19-26 years) and older (62-74 years) adults listened to continuous tones containing rare pitch changes (glides) and short gaps. Glides and gaps could be separated in 150ms, 250ms, 650ms or longer and the task was gap detection while ignoring glides. With longer glide-gap separations similar N1 enhancements were observable in both groups suggesting that the duration of the distracted sensory state was not affected by aging. Older adults responded, however, slower at short glide-gap separations which indicated that distraction at subsequent levels of processing may have nonetheless more impact in older than in younger adults., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The human cognitive system has various functions to enhance performance in tasks requiring responses to stimuli. When potentially occurring stimuli are known, we can establish selective attention sets and ignore task-irrelevant events while attending task-relevant ones. When the stimulation is temporally structured, we can rely on constant temporal relationships between stimulus events to prepare for the task-relevant moments. Most distraction paradigms feature task-irrelevant events which are followed by task-relevant ones within a constant interval, and distraction is induced by randomly replacing some of the standard task-irrelevant events. The constant time interval transforms irrelevant events to task-supportive temporal cues, which are integrated into the task-behavior by the participants. The present study investigated whether distracters could be utilized as temporal cues to support task-related processing in a continuous auditory stimulation paradigm. A continuous tone featuring short and long gaps, and pitch glides was presented. Participants performed a gap duration discrimination task, while ignoring glides. Glides could be presented frequently or rarely. In the informative condition, 80% of the glides predicted the presentation time of the forthcoming gap (400ms), while in the uninformative condition, the occurrence of gaps and glides was independent. Rare glides elicited an enhanced N1, mismatch negativity, and P3 event-related potentials in both informative and uninformative conditions. In informative conditions glides were followed by a contingent negative variation; and rare informative glides elicited an N2b, suggesting that despite triggering distraction-related processes, distracters could be integrated into the task-behavior, and could be utilized as task-supportive cues., (Copyright © 2016 Elsevier B.V. All rights reserved.)

When performing sensory tasks, knowing the potentially occurring goal-relevant and irrelevant stimulus events allows the establishment of selective attention sets, which result in enhanced sensory processing of goal-relevant events. In the auditory modality, such enhancements are reflected in the increased amplitude of the N1 ERP elicited by the onsets of task-relevant sounds. It has been recently suggested that ERPs to task-relevant sound offsets are similarly enhanced in a tone-focused state in comparison to a distracted one. The goal of the present study was to explore the influence of attention on ERPs elicited by sound offsets. ERPs elicited by tones in a duration-discrimination task were compared to ERPs elicited by the same tones in not-tone-focused attentional setting. Tone offsets elicited a consistent, attention-dependent biphasic (positive-negative--P1-N1) ERP waveform for tone durations ranging from 150 to 450 ms. The evidence, however, did not support the notion that the offset-related ERPs reflected an offset-specific attention set: The offset-related ERPs elicited in a duration-discrimination condition (in which offsets were task relevant) did not significantly differ from those elicited in a pitch-discrimination condition (in which the offsets were task irrelevant). Although an N2 reflecting the processing of offsets in task-related terms contributed to the observed waveform, this contribution was separable from the offset-related P1 and N1. The results demonstrate that when tones are attended, offset-related ERPs may substantially overlap endogenous ERP activity in the postoffset interval irrespective of tone duration, and attention differences may cause ERP differences in such postoffset intervals., (© 2016 Society for Psychophysiological Research.)

A number of studies have shown that sounds temporally close to one's own finger movements elicit lower-amplitude auditory event-related potentials (ERPs) than do the same tones when they are only listened to. In these studies, the actions have involved making a mechanical contact with an object. In the present study, the role of mechanical contact with an object was investigated in action-related auditory attenuation. In three experiments, participants performed a time-interval production task. In each experiment, in one condition the action involved touching an object, but no mechanical contact was made in the other. The estimated tone-related ERP contributions to the action-tone coincidence ERP waveforms (calculated by subtracting the action-related ERP from the coincidence ERP) were more attenuated when the action involved moving the finger and making a mechanical contact at the end of the movement. However, when participants kept their finger on a piezoelectric element and applied pressure impulses without moving their finger, the action did not result in stronger attenuation of the tone-related auditory ERP estimates. Although these results may suggest that auditory ERP attenuation is stronger for actions resulting in mechanical impact, they also imply that mechanical impact may confound and lead to the overestimation of auditory ERP attenuation in such paradigms, because the impact may result in faint but audible sounds.

An auditory selective attention set allows one to enhance the processing of goal-relevant sound events, which is reflected by the enhancement of the N1 event-related potential (ERP). The present study investigated whether the sensory consequences of distraction (i.e., involuntary attention changes triggered by infrequent sensory events) can be revealed as the removal of this attentional ERP enhancement. Continuous tones featuring occasional gaps were presented, and participants performed a gap-detection task. Independently from gaps, abrupt pitch changes (glides) were introduced, either rarely or frequently, in separate conditions. Whereas rare glides preceding gaps by 150 ms strongly impacted gap-detection performance and gap-related N1 amplitudes, their impact on gaps following rare glides by 650 ms was significantly smaller in both measures. This result demonstrates the utility of N1 in probing the sensory impact of auditory distraction., (Copyright © 2014 Society for Psychophysiological Research.)

Event-related potentials (ERPs) offer unique insights into processes related to involuntary attention changes triggered by rare, unpredictably occurring sensory events, that is, distraction. Contrasting ERPs elicited by distracters and frequent standard stimuli in oddball paradigms allowed the formulation of a three-stage model describing distraction-related processing: first, the distracting event is highlighted by a sensory filter. Second, attention is oriented towards the event, and finally, the task-optimal attention set is restored, or task priorities are changed. Although this model summarizes how distracting stimulus information is processed, not much is known about the cost of taking this exceptional route of processing. The present study demonstrates the impact of distraction on sensory processing. Participants performed a Go/NoGo tone-duration discrimination task, with infrequent pitch distracters. In the two parts of the experiment the duration-response mapping was reversed. Contrasts of distracter and standard ERPs revealed higher P3a- and reorienting negativity amplitudes for short than for long tones, independently from response type. To understand the cause of these asymmetries, short vs. long ERP contrasts were calculated. The ERP pattern showed that short standards elicited an attention-dependent offset response, which was abolished for short distracters. That is, the apparent P3a- and RON enhancements were caused by the removal of a task-related attentional sensory enhancement. This shows that the disruption of task-optimal attention set precedes the elicitation of the P3a, which suggests that P3a does not reflect a process driving the initial distraction-related attention change.

Maintaining a selective attention set allows us to efficiently perform sensory tasks despite the multitude of concurrent sensory stimuli. Unpredictably occurring, rare events nonetheless capture our attention, that is, we get distracted. The present study investigated the efficiency of control over distraction as a function of preparation time available before a forthcoming distracter. A random sequence of short and long tones (100 or 200 ms with 50-50 % probability) was presented. Independently from tone duration, occasionally (13.3 % of the time), the pitch of a tone was changed. Such rare pitch variants (distracters) usually lead to delayed and less precise discrimination responses, and trigger a characteristic series of event-related potentials (ERPs) reflecting the stages of distraction-related processing: starting with negative ERPs signaling the sensory registration of the distracter; a P3a-usually interpreted as a reflection of involuntary attention change and finally the so-called reorienting negativity signaling the restoration of the task-optimal attention set. In separate conditions, 663 or 346 ms before each tone (long or short cue-tone interval), a visual cue was presented, which signaled whether the forthcoming tone was a distracter (rare pitch variant), with 80 % validity. As reflected by reduced reaction time delays and P3a amplitudes, valid cues led to the prevention of distraction, but only in the long cue-tone interval condition. The analyses of the cue-related P3b and contingent negative variation showed that participants made more effort to utilize cue information to prevent distraction in the long cue-tone than in the short cue-tone interval condition.

The event-related potential (ERP) correlates of sound detection are attenuated when eliciting sounds coincide with our own actions. The role of attention in this effect was investigated in two experiments by presenting tones separated by random intervals. In the homogeneous condition of Experiments 1 and 2, the same tone was repeated, whereas in the mixed condition of Experiment 1, tones with five different frequencies were presented. Participants performed a time-interval production task by marking intervals with keypresses in Experiment 1, and tried to produce keypress-tone coincidences in Experiment 2. Although the auditory ERPs were attenuated for coincidences, no modulation by the multiplicity of tone frequencies in Experiment 1, or by the task-relevancy of tones and coincidences in Experiment 2, was found. This suggests that coincidence-related ERP attenuation cannot be fully explained by voluntary attentional mechanisms., (Copyright © 2013 Society for Psychophysiological Research.)

Stimulus-focused attention enhances the processing of auditory stimuli, which is indicated by enhanced neural activity. In situations where fast responses are required, attention may not only serve as a means to gain more information about the relevant stimulus, but it may provide a processing speed gain as well. In two experiments we investigated whether attentional focusing decreased the latency of the auditory N1 event related potential. In Experiment 1 slowly emerging, soft (20dB sensation level) sounds were presented in two conditions, in which participants performed a sound-detection task or watched a silent movie and ignored the sounds. N1 latency was shorter in the sound-detection task in comparison to the ignore condition. In Experiment 2 we investigated whether the attentional N1 latency-decrease was caused by a frequency-specific attentional preparation or not. To this end, tone sequences were presented with a single tone frequency or with four different frequencies. N1 latency was shorter in the sound-detection task in comparison to the ignore condition regardless the number of frequencies. These results suggest that stimulus-focused attention increases stimulus processing speed by generally increasing sensory gain., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Involuntary attention switches triggered by infrequent, unpredictably occurring sensory events (distraction) can be prevented when participants are made aware of the forthcoming distractor. Previous studies exploring this phenomenon presented visual cues before each stimulus in an auditory oddball sequence. In one condition, cues were completely reliable in predicting the forthcoming distractor or standard sound, in another, separate condition, they were completely unreliable. These studies found that in the condition with reliable cues, distraction was reduced compared to that with unreliable cues, as signaled by decreased reaction time delay as well as reduced P3a and reorienting negativity event-related potentials. Whereas these results are generally interpreted as the results of preparatory processes initiated by the cues, it could be argued that the preventive effect is a byproduct of increased information processing load in the condition with informative cues compared to that in the condition with uninformative ones. In the present study, using 80% reliable visual cues preceding tones in an oddball sequence, it was demonstrated that distraction can be prevented when the trials with valid and invalid cues were presented within a single experimental condition, as shown by reduced reaction time delay and P3a amplitude. These results are compatible with the notion that the distraction is prevented by means of preparatory processes initiated by the cues., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Rare irregular sounds (deviants) embedded into a regular sound sequence have large potential to draw attention to themselves (distraction). It has been previously shown that distraction, as manifested by behavioral response delay, and the P3a and reorienting negativity (RON) event-related potentials, could be reduced when the forthcoming deviant was signaled by visual cues preceding the sounds. In the present study, we investigated the type of information used in the prevention of distraction by manipulating the information content of the visual cues preceding the sounds. Cues could signal the specific variant of the forthcoming deviant, or they could just signal that the next tone was a deviant. We found that stimulus-specific cue information was used in reducing distraction. The results also suggest that early P3a and RON index processes related to the specific deviating stimulus feature, whereas late P3a reflects a general distraction-related process., (Copyright © 2011 Elsevier B.V. All rights reserved.)

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.

Event-related potential (ERP) correlates of distraction are usually investigated in the oddball paradigm following a discrete, trial-by-trial stimulation protocol. In this design, participants perform a discrimination task while oddball stimuli deviate in a task-irrelevant stimulus feature. In our experiment, participants detected gaps in a continuous tone while infrequent frequency glides served as distracting events. Glides preceding a gap by 150ms delayed the response to the gap and elicited the ERP sequence of N1, probably MMN, P3a, and reorienting negativity, suggesting that these responses reflect distraction-related processes which are neither task- nor stimulation-specific. When participants watched a silent movie and the auditory stimulation was task-irrelevant, glides preceding a gap by 150ms enhanced the amplitude of the gap-elicited N1. However, when the auditory stimulation was task-relevant, the gap-elicited N1 was attenuated. These results show that the glides drew attention away from the ongoing task, both from watching the silent movie and from detecting gaps., (Copyright 2010 Elsevier B.V. All rights reserved.)

Behavioral and event-related potential measures of distraction and reorientation were obtained from children (6 years), young (19-24 years) and elderly adults (62-82 years) in an auditory distraction-paradigm. Participants performed a go/nogo duration discrimination task on a sequence of short and long (50-50%) tones. In children, reaction times were longer and discrimination (d') scores were lower than in adults. Occasionally (15%), the pitch of the presented tones was changed. The task-irrelevant feature variation resulted in longer reaction times and lower d' scores with no significant differences between the three groups. Task-irrelevant changes affected the N1 amplitude and elicited the mismatch negativity, N2b, P3 and reorienting negativity (RON) sequence of event-related brain potentials. In children, the P3 latency was the same as in young adults. However the RON component was delayed by about 100ms. In the elderly, P3 and RON were uniformly delayed by about 80ms compared to young adults. This pattern of results provides evidence that distraction influences different processing stages in the three groups. Restoration of the task-optimal attention set was delayed in children, whereas in the elderly, the triggering of involuntary attention-switching required longer time.

Distraction triggered by unexpected events is generally described in a serial model comprising (1) automatic detection of unexpected task-irrelevant events, (2) orienting towards the event, and (3) recovery from distraction. Processes taking place at the three stages are assumed to be reflected by the N1 and mismatch negativity (MMN); the P3a; and the reorienting negativity (RON) event-related potentials (ERPs), respectively. We investigated whether the processes indexed by these components form a strongly coupled chain, each co-varying with the preceding one. To this end, micro-sequence analysis of the ERPs elicited by unpredictable pitch-changes was conducted in an auditory duration discrimination task. Results indicated that the processes indexed by the above-mentioned ERPs are not strongly coupled. Pair-wise dissociations were found between the ERPs reflecting each processing stage: P3a can be elicited without concurrent N1-increase or MMN elicitation and without subsequent elicitation of the RON. Possible interpretations of P3a and RON are discussed.

Distraction is a disruption of a selective attention set triggered by infrequent, unpredictable events. In the present study, two hypotheses on the nature of this attention change were contrasted in the auditory domain: (1) distraction is a specific attention-switch: attention is diverted from the task-relevant to the distracting information or (2) distraction is a general attention resetting, that is, a transition to a general attention set in which the organism is more capable of facing any event. The general attention resetting hypothesis predicts that any infrequent, unpredictable stimulus would trigger distraction, whereas the specific attention-switch hypothesis predicts that such a stimulus triggers distraction only if it deviates in a task-irrelevant stimulus aspect. To test this, a sequence of tone-pairs was presented. The participants' task was to respond according to the direction of within-pair pitch-change. Deviant trials were presented occasionally (10%). In the Relevant Deviance condition, the deviation concerned the task-relevant stimulus aspect (larger within-pair pitch-difference); in the Irrelevant Deviance condition the deviance occurred in a task-irrelevant stimulus aspect (spectral width of the second tone of the pair). In the Double Deviance condition, deviants featured both a larger pitch-difference and a spectral width difference. The elicitation pattern of the N2b/MMN, P3a and late negative components favors the specific attention-switch hypothesis, that is, distraction comprises an involuntary attention shift from the task-relevant information to the distracting one. The presence of deviance-related response time delay in the Relevant Deviance condition suggests that other effects unrelated to distraction also occurred.

The anatomical structures involved in distraction-related processing in the auditory domain were investigated using magnetoencephalography. Participants performed a duration-discrimination task on a sequence of 200 and 400 ms long tones. Infrequent (12%) task-irrelevant pitch changes resulted in slower discriminative responses and more errors. Event-related potentials to these changes show an increased N1, a mismatch negativity, a P3a, and a reorienting negativity. The event-related magnetic fields revealed focal activities in superior and medial temporal areas in the N1/mismatch negativity time range. No significant activity was found in the P3a interval. In the reorienting negativity interval, significant activity was located in the primary motor area. This suggests that action-selection-related activity also contributes to attentional reorientation after distraction.

We investigated the role of attention in feature binding in the auditory and the visual modality. One auditory and one visual experiment used the mismatch negativity (MMN and vMMN, respectively) event-related potential to index the memory representations created from stimulus sequences, which were either task-relevant and, therefore, attended or task-irrelevant and ignored. In the latter case, the primary task was a continuous demanding within-modality task. The test sequences were composed of two frequently occurring stimuli, which differed from each other in two stimulus features (standard stimuli) and two infrequently occurring stimuli (deviants), which combined one feature from one standard stimulus with the other feature of the other standard stimulus. Deviant stimuli elicited MMN responses of similar parameters across the different attentional conditions. These results suggest that the memory representations involved in the MMN deviance detection response encoded the frequently occurring feature combinations whether or not the test sequences were attended. A possible alternative to the memory-based interpretation of the visual results, the elicitation of the McCollough color-contingent aftereffect, was ruled out by the results of our third experiment. The current results are compared with those supporting the attentive feature integration theory. We conclude that (1) with comparable stimulus paradigms, similar results have been obtained in the two modalities, (2) there exist preattentive processes of feature binding, however, (3) conjoining features within rich arrays of objects under time pressure and/or longterm retention of the feature-conjoined memory representations may require attentive processes.

The effects of auditory context on the preattentive and perceptual organization of tone sequences were investigated. Two sets of experiments were conducted in which the pitch of contextual tones was varied, bringing about two different contextual manipulations. Preattentive auditory organization was indexed by the mismatch negativity event-related potential, which is elicited by violations of auditory regularities even when participants ignore the sounds (e.g., by reading a book). The perceptual effects of the contextual manipulations on auditory grouping were assessed using target-detection and order-judgment tasks. The close correspondence found between the effects of auditory context on the perceptual and preattentive measures of auditory grouping suggests that a large part of contextual processing is preattentive.

Regular sequences of sounds (i.e., non-random) can usually be described by several, equally valid rules. Rules allowing extrapolation from one sound to the next are termed local rules, those that define relations between temporally non-adjacent sounds are termed global rules. The aim of the present study was to determine whether both local and global rules can be simultaneously extracted from a sound sequence even when attention is directed away from the auditory stimuli. The pre-attentive representation of a sequence of two alternating tones (differing only in frequency) was investigated using the mismatch negativity (MMN) auditory event-related potential. Both local- and global-rule violations of tone alternation elicited the MMN component while subjects ignored the auditory stimuli. This finding suggests that (a) pre-attentive auditory processes can extract both local and global rules from sound sequences, and (b) that several regularity representations of a sound sequence are simultaneously maintained during the pre-attentive phase of auditory stimulus processing.