Interference in memory by process or content? A reply to Neath (2000)

The phonological store of working memory: A critique and an alternative, perceptual-motor, approach to verbal short-term memory

A key quality of a good theory is its fruitfulness, one measure of which might be the degree to which it compels researchers to test it, refine it, or offer alternative explanations of the same empirical data. Perhaps the most fruitful element of Baddeley and Hitch's (1974) Working Memory framework has been the concept of a short-term phonological store, a discrete cognitive module dedicated to the passive storage of verbal material that is architecturally fractionated from perceptual, language, and articulatory systems. This review discusses how the phonological store construct has served as the main theoretical springboard for an alternative perceptual-motor approach in which serial-recall performance reflects the opportunistic co-opting of the articulatory-planning system and, when auditory material is involved, the products of obligatory auditory perceptual organisation. It is argued that this approach, which rejects the need to posit a distinct short-term store, provides a better account of the two putative empirical hallmarks of the phonological store-the phonological similarity effect and the irrelevant speech effect-and that it shows promise too in being able to account for nonword repetition and word-form learning, the supposed evolved function of the phonological store. The neuropsychological literature cited as strong additional support for the phonological store concept is also scrutinised through the lens of the perceptual-motor approach for the first time and a tentative articulatory-planning deficit hypothesis for the "short-term memory" patient profile is advanced. Finally, the relation of the perceptual-motor approach to other "emergent-property" accounts of short-term memory is briefly considered.

When softer sounds are more distracting: Task-irrelevant whispered speech causes disruption of serial recall

Two competing accounts propose that the disruption of short-term memory by irrelevant speech arises either due to interference-by-process (e.g., changing-state effect) or attentional capture, but it is unclear how whispering affects the irrelevant speech effect. According to the interference-by-process account, whispered speech should be less disruptive due to its reduced periodic spectro-temporal fine structure and lower amplitude modulations. In contrast, the attentional account predicts more disruption by whispered speech, possibly via enhanced listening effort in the case of a comprehended language. In two experiments, voiced and whispered speech (spoken sentences or monosyllabic words) were presented while participants memorized the order of visually presented letters. In both experiments, a changing-state effect was observed regardless of the phonation (sentences produced more disruption than "steady-state" words). Moreover, whispered speech (lower fluctuation strength) was more disruptive than voiced speech when participants understood the language (Experiment 1), but not when the language was incomprehensible (Experiment 2). The results suggest two functionally distinct mechanisms of auditory distraction: While changing-state speech causes automatic interference with seriation processes regardless of its meaning or intelligibility, whispering appears to contain cues that divert attention from the focal task primarily when presented in a comprehended language, possibly via enhanced listening effort.

The impact of environmental noise on drivers' cognitive abilities: A case study on in-vehicle voice interaction interfaces

To investigate the impact of environmental noise on the cognitive abilities of drivers, this study, using in-vehicle voice interaction as an example, conducted laboratory experiments to assess the effects of road traffic noise, entertainment noise, and white noise stimuli on drivers' attention and short-term memory. The noise levels simulated to mimic acoustic conditions during car driving ranged from 35 dB(A) to 65 dB(A). The conclusions drawn were as follows: (1) Noise levels directly influenced subjective annoyance levels, with annoyance linearly increasing as noise levels escalated; (2) Both attention and short-term memory task reaction times of drivers were significantly influenced by noise types. Compared to traffic noise and white noise, drivers' cognitive efficiency was lower under entertainment noise. (3) Performance in complex cognitive tasks was more susceptible to noise levels compared to simple cognitive tasks; (4) Experimentally, it was found that drivers exhibited the highest cognitive efficiency in cognitive tasks when the environmental noise level was 55 dB(A), as opposed to noise levels of 35 dB(A), 45 dB(A), and 65 dB(A).

False memories through auditory distraction: When irrelevant speech produces memory intrusions in the absence of semantic interference

Task-irrelevant speech is known to cause disruption of short-term memory, either through specific interference with encoding processes (e.g., seriation, semantic processing) or by diverting attention from the focal task. Previous studies found that semantically related background speech can induce memory intrusions of words that were not part of the to-be-remembered list. While these findings suggest false memories due to semantic interference, the present study aims to test whether the presence of task-irrelevant speech affects the susceptibility to memory intrusions also in the absence of semantic interference. Therefore, incomprehensible to-be-ignored speech was presented during encoding of semantically related words. It was found across three experiments that incomprehensible changing-state speech increased the rate of false memories of non-presented but semantically related words in a subsequent recognition (Experiments 1 and 2) or recall test (Experiment 3), compared with white noise or steady-state speech. The findings indicate that speech interfered with serial-order processing of the to-be-remembered items, thus urging participants to rely on semantic information to encode and retrieve the presented words. While a focus on semantic information enabled participants to correctly recollect the majority of presented words, it most likely also increased the proportion of false memories of words with semantic associations to the presented words both in recall and recognition tests. In all three experiments, the presence of an auditory deviant in background speech did not increase the rate of false memories, suggesting that attentional capture alone does not necessarily induce source monitoring errors. However, Experiment 3 revealed that an increase in visual task-encoding load attenuated the changing-state effect on the production of false memories. This indicates that the semantic organisation processes initiated as a result of the loss of order information in case of changing-state speech may be sensitive to attentional control.

Is Recognition of Speech in Noise Related to Memory Disruption Caused by Irrelevant Sound?

Listeners with normal audiometric thresholds show substantial variability in their ability to understand speech in noise (SiN). These individual differences have been reported to be associated with a range of auditory and cognitive abilities. The present study addresses the association between SiN processing and the individual susceptibility of short-term memory to auditory distraction (i.e., the irrelevant sound effect [ISE]). In a sample of 67 young adult participants with normal audiometric thresholds, we measured speech recognition performance in a spatial listening task with two interfering talkers (speech-in-speech identification), audiometric thresholds, binaural sensitivity to the temporal fine structure (interaural phase differences [IPD]), serial memory with and without interfering talkers, and self-reported noise sensitivity. Speech-in-speech processing was not significantly associated with the ISE. The most important predictors of high speech-in-speech recognition performance were a large short-term memory span, low IPD thresholds, bilaterally symmetrical audiometric thresholds, and low individual noise sensitivity. Surprisingly, the susceptibility of short-term memory to irrelevant sound accounted for a substantially smaller amount of variance in speech-in-speech processing than the nondisrupted short-term memory capacity. The data confirm the role of binaural sensitivity to the temporal fine structure, although its association to SiN recognition was weaker than in some previous studies. The inverse association between self-reported noise sensitivity and SiN processing deserves further investigation.

The dual effect of background music on creativity: perspectives of music preference and cognitive interference

Music, an influential environmental factor, significantly shapes cognitive processing and everyday experiences, thus rendering its effects on creativity a dynamic topic within the field of cognitive science. However, debates continue about whether music bolsters, obstructs, or exerts a dual influence on individual creativity. Among the points of contention is the impact of contrasting musical emotions-both positive and negative-on creative tasks. In this study, we focused on traditional Chinese music, drawn from a culture known for its 'preference for sadness,' as our selected emotional stimulus and background music. This choice, underrepresented in previous research, was based on its uniqueness. We examined the effects of differing music genres (including vocal and instrumental), each characterized by a distinct emotional valence (positive or negative), on performance in the Alternative Uses Task (AUT). To conduct this study, we utilized an affective arousal paradigm, with a quiet background serving as a neutral control setting. A total of 114 participants were randomly assigned to three distinct groups after completing a music preference questionnaire: instrumental, vocal, and silent. Our findings showed that when compared to a quiet environment, both instrumental and vocal music as background stimuli significantly affected AUT performance. Notably, music with a negative emotional charge bolstered individual originality in creative performance. These results lend support to the dual role of background music in creativity, with instrumental music appearing to enhance creativity through factors such as emotional arousal, cognitive interference, music preference, and psychological restoration. This study challenges conventional understanding that only positive background music boosts creativity and provides empirical validation for the two-path model (positive and negative) of emotional influence on creativity.

Can synchronised tones facilitate immediate memory for printed lists?

In verbal list recall, adding features redundant with the ones to be recalled theoretically could assist recall, by providing additional retrieval cues, or it could impede recall, by draining attention away from the features to be recalled. We examined young adults' immediate memory of lists of printed digits when these lists were sometimes accompanied by synchronised, concurrent tones, one per digit. Unlike most previous irrelevant-sound effects, the tones were not asynchronous with the printed items, which can corrupt the episodic record, and did not repeat within a list. Memory of the melody might bring to mind the associated digits like lyrics in a song. Sometimes there were instructions to sing the digits covertly in the tone pitches. In three experiments, there was no evidence that these methods enhanced memory. Instead, there appeared to be a distraction effect from the synchronised tones, as in the irrelevant sound effect with asynchronised tones.

Irrelevant speech impairs serial recall of verbal but not spatial items in children and adults

Immediate serial recall of visually presented items is reliably impaired by task-irrelevant speech that the participants are instructed to ignore ("irrelevant speech effect," ISE). The ISE is stronger with changing speech tokens (words or syllables) when compared to repetitions of single tokens ("changing-state effect," CSE). These phenomena have been attributed to sound-induced diversions of attention away from the focal task (attention capture account), or to specific interference of obligatory, involuntary sound processing with either the integrity of phonological traces in a phonological short-term store (phonological loop account), or the efficiency of a domain-general rehearsal process employed for serial order retention (changing-state account). Aiming to further explore the role of attention, phonological coding, and serial order retention in the ISE, we analyzed the effects of steady-state and changing-state speech on serial order reconstruction of visually presented verbal and spatial items in children (n = 81) and adults (n = 80). In the verbal task, both age groups performed worse with changing-state speech (sequences of different syllables) when compared with steady-state speech (one syllable repeated) and silence. Children were more impaired than adults by both speech sounds. In the spatial task, no disruptive effect of irrelevant speech was found in either group. These results indicate that irrelevant speech evokes similarity-based interference, and thus pose difficulties for the attention-capture and the changing-state account of the ISE.

Recognition of brief sounds in rapid serial auditory presentation

Two experiments were conducted to test the role of participant factors (i.e., musical sophistication, working memory capacity) and stimulus factors (i.e., sound duration, timbre) on auditory recognition using a rapid serial auditory presentation paradigm. Participants listened to a rapid stream of very brief sounds ranging from 30 to 150 milliseconds and were tested on their ability to distinguish the presence from the absence of a target sound selected from various sound sources placed amongst the distracters. Experiment 1a established that brief exposure to stimuli (60 to 150 milliseconds) does not necessarily correspond to impaired recognition. In Experiment 1b we found evidence that 30 milliseconds of exposure to the stimuli significantly impairs recognition of single auditory targets, but the recognition for voice and sine tone targets impaired the least, suggesting that the lower limit required for successful recognition could be lower than 30 milliseconds for voice and sine tone targets. Critically, the effect of sound duration on recognition completely disappeared when differences in musical sophistication were controlled for. Participants' working memory capacities did not seem to predict their recognition performances. Our behavioral results extend the studies oriented to understand the processing of brief timbres under temporal constraint by suggesting that the musical sophistication may play a larger role than previously thought. These results can also provide a working hypothesis for future research, namely, that underlying neural mechanisms for the processing of various sound sources may have different temporal constraints.

Doubts About the Role of Rehearsal in the Irrelevant Sound Effect

Abstract. The irrelevant sound effect (ISE) describes the disruption of processes involved in maintaining information in working memory (WM) when irrelevant noise is present in the environment. While some posit that the ISE arises due to split obligation of attention to the irrelevant sound and the to-be-remembered information, others have argued that background noise corrupts the order of information within WM. Support for the latter position comes from research showing that the ISE appears to be most robust in tasks that emphasize ordered maintenance by a serial rehearsal strategy, and diminished when rehearsal is discouraged or precluded by task characteristics. This prior work confounds the demand for seriation with rehearsal. Thus, the present study aims to disentangle ordered maintenance from a rehearsal strategy by using a running memory span task that requires ordered output but obviates the utility of rehearsal. Across four experiments, we find a significant ISE that persists under conditions that should discourage the use of rehearsal and among individuals who self-report use of alternative strategies. These findings indicate that rehearsal is not necessary to produce an ISE in a serial recall task and thus fail to corroborate accounts of the ISE that emphasize the involvement of rehearsal.

Selective memory disrupted in intra-modal dual-task encoding conditions

Given natural memory limitations, people can generally attend to and remember high-value over low-value information even when cognitive resources are depleted in older age and under divided attention during encoding, representing an important form of cognitive control. In the current study, we examined whether tasks requiring overlapping processing resources may impair the ability to selectively encode information in dual-task conditions. Participants in the divided-attention conditions of Experiment 1 completed auditory tone-distractor tasks that required them to discriminate between tones of different pitches (audio-nonspatial) or auditory channels (audio-spatial), while studying items in different locations in a grid (visual-spatial) differing in reward value. Results indicated that, while reducing overall memory accuracy, neither cross-modal auditory distractor task influenced participants' ability to selectively encode high-value items relative to a full attention condition, suggesting maintained cognitive control. Participants in Experiment 2 studied the same important visual-spatial information while completing demanding color (visual-nonspatial) or pattern (visual-spatial) discrimination tasks during study. While the cross-modal visual-nonspatial task did not influence memory selectivity, the intra-modal visual-spatial secondary task eliminated participants' sensitivity to item value. These results add novel evidence of conditions of impaired cognitive control, suggesting that the effectiveness of top-down, selective encoding processes is attenuated when concurrent tasks rely on overlapping processing resources.

Decomposing the role of rehearsal in auditory distraction during serial recall

According to the interference-by-process mechanism of auditory distraction, irrelevant changing sounds interfere with subvocal articulatory-motor sequencing during rehearsal. However, previous attempts to limit rehearsal with concurrent articulation and examine the residual irrelevant sound effect have limited both cumulative rehearsal as well as the initial assembly of articulatory-phonological labels. The current research decomposed rehearsal into these two levels of articulatory-phonological sequencing: silent concurrent articulation limits the availability of both serial repetition and articulatory-phonological recoding; rapid serial visual presentation allows for articulatory-phonological recoding but presents items too quickly for cumulative serial repetition. As predicted by the interference-by-process account, concurrent articulation -- but not rapid serial visual presentation -- reduced the irrelevant sound effect. Not only did the irrelevant sound effect persist in the face of rapid serial visual presentation, a steady-state effect also emerged. These findings indicate that irrelevant sounds interfere with both serial processing at the level of articulatory-motor planning at the word level as well as in the formation of item-to-item associations created via serial repetition of complete items. Moreover, these findings highlight the benefits of articulatory-phonological recoding - independent of pure rehearsal -- within serial recall.

The relation between the intelligibility of irrelevant speech and cognitive performance-A revised model based on laboratory studies

Irrelevant background speech causes dissatisfaction and impairs cognitive performance in open-plan offices. The model of Hongisto (2005, Indoor Air, 15, 458-468) predicts the relation between cognitive performance and the intelligibility of speech described with an objectively measured quantity, the Speech Transmission Index (STI). The model has impacted research in psychology and room acoustics as well as the acoustic design guidelines of offices. However, the model was based on scarce empirical data. The aim of this study was to revise the model based on a systematic literature review, focusing on laboratory experiments manipulating the STI of speech by wide-band steady-state noise. Fourteen studies reporting altogether 34 tests of the STI-performance relation were included. According to Model 1 that includes all tests, performance begins to decrease approximately above STI = 0.21 while the maximum decrease is reached at STI = 0.44. Verbal short-term memory tasks were most strongly and very consistently affected by the STI of speech. The model for these tasks showed a deterioration in performance between STI 0.12 and 0.51. Some evidence of an STI-performance relation was found in verbal working memory tasks and limited evidence in complex verbal tasks. Further research is warranted, particularly concerning task-specific effects.

How the deployment of visual attention modulates auditory distraction

Classically, attentional selectivity has been conceptualized as a passive by-product of capacity limits on stimulus processing. Here, we examine the role of more active cognitive control processes in attentional selectivity, focusing on how distraction from task-irrelevant sound is modulated by levels of task engagement in a visually presented short-term memory task. Task engagement was varied by manipulating the load involved in the encoding of the (visually presented) to-be-remembered items. Using a list of Navon letters (where a large letter is composed of smaller, different-identity letters), participants were oriented to attend and serially recall the list of large letters (low encoding load) or to attend and serially recall the list of small letters (high encoding load). Attentional capture by a single deviant noise burst within a task-irrelevant tone sequence (the deviation effect) was eliminated under high encoding load (Experiment 1). However, distraction from a continuously changing sequence of tones (the changing-state effect) was immune to the influence of load (Experiment 2). This dissociation in the amenability of the deviation effect and the changing-state effect to cognitive control supports a duplex-mechanism over a unitary-mechanism account of auditory distraction in which the deviation effect is due to attentional capture whereas the changing-state effect reflects direct interference between the processing of the sound and processes involved in the focal task. That the changing-state effect survives high encoding load also goes against an alternative explanation of the attenuation of the deviation effect under high load in terms of the depletion of a limited perceptual resource that would result in diminished auditory processing.

Irrelevant music: How suprasegmental changes of a melody's tempo and mode affect the disruptive potential of music on serial recall

On tests of verbal short-term memory, performance declines as a function of auditory distraction. The negative impact of to-be-ignored sound on serial recall is known as the irrelevant sound effect. It can occur with speech, sine tones, and music. Moreover, sound that changes acoustically from one token to the next (i.e., changing-state sound) is more disruptive to serial recall than repetitive, steady-state sound. We tested manipulations that resulted in changes in (higher levels of) perceptual organization for more complex tonal stimuli. Within a trial, the first two bars of a well-known melody were repeated (a) in the exact same manner, (b) with variations only in tempo, (c) with variations only in mode (e.g., Dorian or Phrygian), or (d) with variations in both tempo and mode. Participants serially recalled digits in each of the irrelevant sound conditions as well as in a silent control condition. In Experiment 1a, we tested non-music students and, to investigate whether musical expertise affected the findings, additionally tested students majoring in music in Experiment 1b. Across both samples, recall in the irrelevant sound conditions was significantly poorer than in the silent control condition, but only the tempo variation caused an additional harmful effect. The mode variation did not affect recall performance, in either music or non-music students. These findings indicate that, at least with music, changes are a matter of degree and not every additional variation impairs recall performance.

Are individual differences in auditory processing related to auditory distraction by irrelevant sound? A replication study

Irrelevant sounds can be very distracting, especially when trying to recall information according to its serial order. The irrelevant sound effect (ISE) has been studied in the literature for more than 40 years, yet many questions remain. One goal that has received little attention involves the discernment of a predictive factor, or individual difference characteristic, that would help to determine the size of the ISE. The current experiments were designed to replicate and extend prior work by Macken, Phelps, and Jones (Psychonomic Bulletin & Review, 16, 139–144, 2009), who demonstrated a significant predictive relationship between the size of the ISE and a type of auditory processing called global pattern matching. The authors also found a relationship between auditory processing involving deliberate recoding of sounds and serial order recall performance in silence. Across two experiments, this dissociation was not replicated. Additionally, the two types of auditory processing were not significantly correlated with each other. The lack of a clear pattern of findings replicating the Macken et al. (Psychonomic Bulletin & Review, 16, 139–144, 2009) study raises several questions regarding the need for future research on the characteristics of these auditory processing tasks, and the stability of the measurement of the ISE itself.

Irrelevant sound interference on phonological and tonal working memory in musicians and nonmusicians

BACKGROUND

Working memory refers to the cognitive system responsible for the temporary storage and maintenance of information, but it remains controversial whether overlapping processes underlie the temporary retention of verbal and musical information such as words and tones.

METHODS

Participants with little or no musical training (n = 22) and professional musicians (n = 21) were administered four memory tasks. Two tasks (tone sequence recognition and pseudoword sequence recall) aimed at comparing groups' performance for tonal or phonological material separately. Other two memory tasks investigated pseudoword and tone recognition under three conditions during the retention interval (silence, irrelevant words, or irrelevant tones).

RESULTS

Musicians were better than nonmusicians in tone sequence recognition but not in pseudoword sequence recall. There were no interference effects of irrelevant tones or words on pseudoword recognition, and only irrelevant tones significantly interfered with tone recognition.

CONCLUSIONS

Our results offer further support that tone recognition is specifically impaired by irrelevant tones, but irrelevant words did not disrupt pseudoword or tone recognition. Although these results do not reflect a double-dissociation pattern between phonological and tonal working memory, they provide evidence that temporary retention of tonal information is subject to specific tonal interference, indicating that working memory for tones involves specific processes.

Is auditory distraction by changing-state and deviant sounds underpinned by the same mechanism? Evidence from pupillometry

The mere presence of task-irrelevant auditory stimuli is known to interfere with cognitive functioning. Disruption can be caused by changing auditory distractors (the changing-state effect) or by a sound that deviates from the auditory background (the deviation effect). The unitary account of auditory distraction explains both phenomena in terms of attentional capture whereas the duplex-mechanism account posits that they reflect two fundamentally different forms of distraction in which only the deviation effect is caused by attentional capture. To test these predictions, we exploited a physiological index of attention orienting: the pupillary dilation response (PDR). Participants performed visual serial recall while ignoring sequences of spoken letters. These sequences either comprised repeated or changing letters, and one letter could sometimes be replaced by pink noise (the deviant). Recall was poorer in both changing-state and deviant trials. Interestingly, the PDR was elicited by deviant sounds but not changing-state sounds, while a tonic increase in pupil size was found throughout changing-state trials. This physiological dissociation of the changing-state and the deviation effects suggests they are subtended by distinct mechanisms thereby procuring support for the duplex-mechanism account over the unitary account.

Differences in Auditory Distraction between Adults and Children: A Duplex-mechanism Approach

Differences in the impact of irrelevant sound on recall performance in children (aged 7–9 years old; N = 89) compared to adults (aged 18–22 years old; N = 89) were examined. Tasks that required serial rehearsal (serial and probed-order recall tasks) were contrasted with one that did not (the missing-item task) in the presence of irrelevant sound that was either steady-state (a repeated speech token), changing-state (two alternating speech tokens) and, for the first time with a child sample, could also contain a deviant token (a male-voice token embedded in a sequence otherwise spoken in a female voice). Participants either completed tasks in which the to-be-remembered list-length was adjusted to individual digit span or was fixed at one item greater than the average span we observed for the age-group. The disruptive effects of irrelevant sound did not vary across the two methods of determining list-length. We found that tasks encouraging serial rehearsal were especially affected by changing-state sequences for both age-groups (i.e., the changing-state effect) and there were no group differences in relation to this effect. In contrast, disruption by a deviant sound—generally assumed to be the result of attentional diversion—was evident among children in all three tasks while adults were less susceptible to this effect. This pattern of results suggests that developmental differences in distraction are due to differences in attentional control rather than serial rehearsal efficiency.

Can 'Hebb' Be Distracted? Testing the Susceptibility of Sequence Learning to Auditory Distraction

Sequence learning plays a key role in many daily activities such as language and skills acquisition. The present study sought to assess the nature of the Hebb repetition effect—the enhanced serial recall for a repeated sequence of items compared to random sequences—by examining the vulnerability of this classical sequence-learning phenomenon to auditory distraction. Sound can cause unwanted distraction by either interfering specifically with the processes involved in the focal task (interference-by-process), or by diverting attention away from a focal task (attentional capture). Participants were asked to perform visual serial recall, in which one to-be-remembered sequence was repeated every four trials, while ignoring irrelevant sound. Whereas both changing-state (Experiment 1) and deviant sounds (Experiment 2) disrupted recall performance compared to steady-state sounds, performance for the repeated sequence increased across repetitions at the same rate regardless of the sound condition. Such findings suggest that Hebbian sequence learning is impervious to environmental interference, which provides further evidence that the Hebb repetition effect is an analogue of word-form learning.

Irrelevant Sound Disrupts Speech Production: Exploring the Relationship between Short-Term Memory and Experimentally Induced Slips of the Tongue

To explore the relationship between short-term memory and speech production, we developed a speech error induction technique. The technique, which was adapted from a Japanese word game, exposed participants to an auditory distractor word immediately before the utterance of a target word. In Experiment 1, the distractor words that were phonologically similar to the target word led to a greater number of errors in speaking the target than did the dissimilar distractor words. Furthermore, the speech error scores were significantly correlated with memory span scores. In Experiment 2, memory span scores were again correlated with the rate of the speech errors that were induced from the task-irrelevant speech sounds. Experiment 3 showed a strong irrelevant-sound effect in the serial recall of nonwords. The magnitude of the irrelevant-sound effects was not affected by phonological similarity between the to-be-remembered nonwords and the irrelevant-sound materials. Analysis of recall errors in Experiment 3 also suggested that there were no essential differences in recall error patterns between the dissimilar and similar irrelevant-sound conditions. Weproposed two different underlying mechanisms in immediate memory, one operating via the phonological short-term memory store and the other via the processes underpinning speech production.

Disruption of Verbal Stm by Irrelevant Speech, Articulatory Suppression, and Manual Tapping: Do they have a Common Source?

Under appropriate conditions, immediate serial verbal recall is impaired by irrelevant speech, articulatory suppression, and syncopated tapping. Interpretation of these variables in terms of the phonological loop component of working memory assumes separate phonological storage and articulatory rehearsal processes. In contrast, the Object-Oriented Episodic Record (O-OER) of Jones and the feature theory of Neath interpret these and other phenomena in terms of a unitary multimodal system. Three experiments investigate these disrupting tasks, with each experiment emphasizing one parameter. In each case, recall of phonologically similar and dissimilar letter sequences is compared as a marker of the presence or absence of phonological coding. In Experiment 1, subjects heard or articulated a single item, or tapped a single key at equal intervals. Only articulatory suppression impaired performance; it also abolished the effects of phonological similarity. Experiment 2 was identical, except that items were heard, or generated in a syncopated rhythm. Both suppression and tapping impaired performance to an equivalent extent and obliterated the effect of phonological similarity. Syncopated irrelevant speech caused a modest but significant impairment in performance. Experiment 3 was identical to Experiment 1, except that six tokens were used. Irrelevant speech and tapping had a clear impact on recall, but neither removed the phonological similarity effect. Again articulatory suppression had a major impact on performance and removed the effect of phonological similarity. We conclude that the pattern of results readily fits the phonological loop hypothesis, provided one accepts Saito's proposal that generating syncopated sequences uses common processes with speech production. It is not clear how the results can be explained by either the O-OER or the feature hypothesis.

Noise disturbance in open-plan study environments: a field study on noise sources, student tasks and room acoustic parameters

The aim of this study is to gain more insight in the assessment of noise in open-plan study environments and to reveal correlations between noise disturbance experienced by students and the noise sources they perceive, the tasks they perform and the acoustic parameters of the open-plan study environment they work in. Data were collected in five open-plan study environments at universities in the Netherlands. A questionnaire was used to investigate student tasks, perceived sound sources and their perceived disturbance, and sound measurements were performed to determine the room acoustic parameters. This study shows that 38% of the surveyed students are disturbed by background noise in an open-plan study environment. Students are mostly disturbed by speech when performing complex cognitive tasks like studying for an exam, reading and writing. Significant but weak correlations were found between the room acoustic parameters and noise disturbance of students. Practitioner Summary: A field study was conducted to gain more insight in the assessment of noise in open-plan study environments at universities in the Netherlands. More than one third of the students was disturbed by noise. An interaction effect was found for task type, source type and room acoustic parameters.

Cross-modal Informational Masking of Lipreading by Babble

Whereas the energetic and informational masking effects of unintelligible babble on auditory speech recognition are well established, the present study is the first to investigate its effects on visual speech recognition. Young and older adults performed two lipreading tasks while simultaneously experiencing either quiet, speech-shaped noise, or 6-talker background babble. Both words at the end of uninformative carrier sentences and key words in everyday sentences were harder to lipread in the presence of babble than in the presence of speech-shaped noise or quiet. Contrary to the inhibitory deficit hypothesis of cognitive aging, babble had equivalent effects on young and older adults. In a follow-up experiment, neither the babble nor the speech-shaped noise stimuli interfered with performance of a face-processing task, indicating that babble selectively interferes with visual speech recognition and not with visual perception tasks per se. The present results demonstrate that babble can produce cross-modal informational masking and suggest a breakdown in audiovisual scene analysis, either because of obligatory monitoring of even uninformative speech sounds or because of obligatory efforts to integrate speech sounds even with uncorrelated mouth movements.

Unmasking the effects of masking on performance: The potential of multiple-voice masking in the office environment

Broadband noise is often used as a masking sound to combat the negative consequences of background speech on performance in open-plan offices. As office workers generally dislike broadband noise, it is important to find alternatives that are more appreciated while being at least not less effective. The purpose of experiment 1 was to compare broadband noise with two alternatives-multiple voices and water waves-in the context of a serial short-term memory task. A single voice impaired memory in comparison with silence, but when the single voice was masked with multiple voices, performance was on level with silence. Experiment 2 explored the benefits of multiple-voice masking in more detail (by comparing one voice, three voices, five voices, and seven voices) in the context of word processed writing (arguably a more office-relevant task). Performance (i.e., writing fluency) increased linearly from worst performance in the one-voice condition to best performance in the seven-voice condition. Psychological mechanisms underpinning these effects are discussed.

Hemispheric specialization in selective attention and short-term memory: a fine-coarse model of left- and right-ear disadvantages

Serial short-term memory is impaired by irrelevant sound, particularly when the sound changes acoustically. This acoustic effect is larger when the sound is presented to the left compared to the right ear (a left-ear disadvantage). Serial memory appears relatively insensitive to distraction from the semantic properties of a background sound. In contrast, short-term free recall of semantic-category exemplars is impaired by the semantic properties of background speech and is relatively insensitive to the sound's acoustic properties. This semantic effect is larger when the sound is presented to the right compared to the left ear (a right-ear disadvantage). In this paper, we outline a speculative neurocognitive fine-coarse model of these hemispheric differences in relation to short-term memory and selective attention, and explicate empirical directions in which this model can be critically evaluated.

Auditory Distraction Eliminates Retrieval Induced Forgetting

The Retrieval-Induced Forgetting (RIF) paradigm includes three phases: (a) study/encoding of category exemplars, (b) practicing retrieval of a sub-set of those category exemplars, and (c) recall of all exemplars. At the final recall phase, recall of items that belong to the same categories as those items that undergo retrieval practice, but that did not undergo retrieval practice themselves, is impaired. The received view is that this is because retrieval of target category-exemplars (e.g., “Tiger” in the category Four-legged animal) requires inhibition of nontarget category-exemplars (e.g., “Dog” and “Lion”) that compete for retrieval. Here, we used the RIF paradigm to investigate whether ignoring auditory items during the retrieval-practice phase modulates the inhibitory process. In two experiments, RIF was present when retrieval practice was conducted in quiet and when it was conducted in the presence of spoken words that were drawn from a different category to that from which the targets for retrieval practice were selected. In contrast, RIF was abolished when words that were either identical to, or merely semantically related to, the retrieval-practice words were presented as background speech. The results suggest that the act of ignoring speech can reduce inhibition of the non-practiced category-exemplars, thereby eliminating RIF, but only when the spoken words are competitors for retrieval (i.e., belong to the same semantic category as the to-be-retrieved items).

Investigating the role of attentional resources in the irrelevant speech effect

Irrelevant words can be disruptive to performance, and the frequency of usage of the irrelevant words has affected the magnitude of such disruption (Buchner & Erdfelder, 2005). The finding of word frequency differences in the magnitude of the irrelevant speech effect (ISE) implicated a role for attentional processes. Using a different conceptualization of attention, researchers have found that individual differences in working memory capacity did not predict the magnitude of the ISE, which questioned the role of attentional control (Beaman, 2004; Sörqvist, 2010). The current study investigated aspects of the construct of attention and the ISE, using both individual and developmental difference approaches. Results showed no significant difference between serial recall performances in the presence of high or low word frequency distractors. Furthermore, effects of working memory capacity differences were not found, but children displayed a larger ISE than college students. The weight of the evidence appears against an attentional resource view of the ISE.

Attention, working memory, and grammaticality judgment in typical young adults

PURPOSE

To examine resource allocation and sentence processing, this study examined the effects of auditory distraction on grammaticality judgment (GJ) of sentences varied by semantics (reversibility) and short-term memory requirements.

METHOD

Experiment 1: Typical young adult females (N = 60) completed a whole-sentence GJ task in distraction (Quiet, Noise, or Talk). Participants judged grammaticality of Passive sentences varied by sentence (length), grammaticality, and reversibility. Reaction time (RT) data were analyzed using a mixed analysis of variance. Experiment 2: A similar group completed a self-paced reading GJ task using the similar materials.

RESULTS

Experiment 1: Participants responded faster to Bad and to Nonreversible sentences, and in the Talk distraction. The slowest RTs were noted for Good-Reversible-Padded sentences in the Quiet condition. Experiment 2: Distraction did not differentially affect RTs for sentence components. Verb RTs were slower for Reversible sentences.

CONCLUSIONS

Results suggest that narrative distraction affected GJ, but by speeding responses, not slowing them. Sentence variables of memory and reversibility slowed RTs, but narrative distraction resulted in faster processing times regardless of individual sentence variables. More explicit, deliberate tasks (self-paced reading) resulted in less effect from distraction. Results are discussed in terms of recent theories about auditory distraction.

Task switching and serial memory: looking into the nature of switches and tasks

Task switching research has so far focused on the impact of switching task-sets between two-choice classification tasks that require little or no memory load. Empirical work is lacking however to determine whether the switching cost can be extended to other cognitive activities and to different types of switches. In the present study, switching between the content - verbal to spatial - of the tasks was contrasted with switching cognitive processes - categorization to serial memory. Our pattern of results revealed the absence of local and general switch costs on serial memory tasks, while substantial costs were observed with two-choice judgement tasks. Such a finding challenges the widely accepted assumption that task alternation comes with a considerable cost in performance regardless of the cognitive tasks undertaken. Our results are discussed in context of the predominant models of task switching.

Moving through imagined space: Mentally simulating locomotion during spatial description reading

Readers mentally simulate the perceptual and motoric elements related through text. Sound is one perceptual characteristic of these embodied simulations that has received little attention. Two experiments tested whether movement sounds (walking vs. running) or metronome pulses (fast vs. slow) would modulate reading speed and memory for two different types of spatial descriptions, route and survey. Route descriptions describe environments from a first-person, ground-level perspective whereas survey descriptions use an aerial overview perspective. Experiment 1 demonstrated that route description readers altered their reading speed in correspondence with both movement and metronome sounds, progressing through descriptions faster when hearing fast-paced versus slow-paced sounds. When reading survey descriptions, however, readers only modulated their reading speed while listening to metronome pulses. Those who showed the greatest reading time effects with the route description and footstep sounds also showed difficulty solving inferences from the survey perspective. Experiment 2 demonstrated that movement sounds influenced perceptions of distance traveled such that estimates of environmental scale increased after listening to running versus walking sounds. Taken together these results demonstrate that route description readers mentally simulate a journey through a described world, and these simulations and the resulting spatial memories can be guided by auditory information.

Evaluating models of working memory through the effects of concurrent irrelevant information

Working memory is believed to play a central role in almost all domains of higher cognition, yet the specific mechanisms involved in working memory are still fiercely debated. We describe a neuroimaging experiment with functional magnetic resonance imaging (fMRI) and a companion behavioral experiment, and in both we seek to adjudicate between alternative theoretical models of working memory on the basis of the effects of interference from articulatory suppression, irrelevant speech, and irrelevant nonspeech. In Experiment 1 we examined fMRI signal changes induced by each type of irrelevant information while subjects performed a probed recall task. Within a principally frontal and left-lateralized network of brain regions, articulatory suppression caused an increase in activity during item presentation, whereas both irrelevant speech and nonspeech caused relative activity reductions during the subsequent delay interval. In Experiment 2, the specific timing of interference was manipulated in a delayed serial recall task. Articulatory suppression was found to be most consequential when it coincided with item presentation, whereas both irrelevant speech and irrelevant nonspeech effects were strongest when limited to the subsequent delay period. Taken together, these experiments provide convergent evidence for a dissociation of articulatory suppression from the 2 irrelevant sound conditions. Implications of these findings are considered for 4 prominent theories of working memory.

Neural organization of linguistic short-term memory is sensory modality-dependent: evidence from signed and spoken language

Despite decades of research, there is still disagreement regarding the nature of the information that is maintained in linguistic short-term memory (STM). Some authors argue for abstract phonological codes, whereas others argue for more general sensory traces. We assess these possibilities by investigating linguistic STM in two distinct sensory-motor modalities, spoken and signed language. Hearing bilingual participants (native in English and American Sign Language) performed equivalent STM tasks in both languages during functional magnetic resonance imaging. Distinct, sensory-specific activations were seen during the maintenance phase of the task for spoken versus signed language. These regions have been previously shown to respond to nonlinguistic sensory stimulation, suggesting that linguistic STM tasks recruit sensory-specific networks. However, maintenance-phase activations common to the two languages were also observed, implying some form of common process. We conclude that linguistic STM involves sensory-dependent neural networks, but suggest that sensory-independent neural networks may also exist.

Irrelevant speech effects and statistical learning

Immediate serial recall of visually presented verbal stimuli is impaired by the presence of irrelevant auditory background speech, the so-called irrelevant speech effect. Two of the three main accounts of this effect place restrictions on when it will be observed, limiting its occurrence either to items processed by the phonological loop (the phonological loop hypothesis) or to items that are not too dissimilar from the irrelevant speech (the feature model). A third, the object-oriented episodic record (O-OER) model, requires only that the memory task involves seriation. The present studies test these three accounts by examining whether irrelevant auditory speech will interfere with a task that does not involve the phonological loop, does not use stimuli that are compatible with those to be remembered, but does require seriation. Two experiments found that irrelevant speech led to lower levels of performance in a visual statistical learning task, offering more support for the O-OER model and posing a challenge for the other two accounts.