Differences in Speech Recognition Between Children with Attention Deficits and Typically Developed Children Disappear When Exposed to 65 dB of Auditory Noise

Systematic Review and Meta-Analysis: Do White Noise or Pink Noise Help With Task Performance in Youth With Attention-Deficit/Hyperactivity Disorder or With Elevated Attention Problems?

OBJECTIVE

Public interest in the potential benefits of white, pink, and brown noise for attention-deficit/hyperactivity disorder (ADHD) has recently mushroomed. White noise contains all frequencies of noise and sounds like static; pink or brown noise has more power in the lower frequencies and may sound, respectively, like rain or a waterfall. This meta-analysis evaluated effects on laboratory tasks in individuals with ADHD or elevated ADHD symptoms.

METHOD

Eligible studies reported on participants with diagnosis of ADHD or elevated symptoms of ADHD who were assessed in a randomized trial using laboratory tasks intended to measure aspects of attention or academic work involving attention or executive function while exposed to white, pink, and brown noise and compared with a low/no noise condition. Two authors independently reviewed and screened studies for eligibility. A random-effects meta-analysis was conducted with preplanned moderator analyses of age, diagnostic status, and task type. Publication bias was evaluated. The GRADE tool was used to assess certainty of the evidence. Sensitivity analyses were conducted to evaluate robustness.

RESULTS

Studies of children and college-age young adults with ADHD or ADHD symptoms (k = 13, N = 335) yielded a small but statistically significant benefit of white and pink noise on task performance (g = 0.249, 95% CI [0.135, 0.363], p < .0001). No studies of brown noise were identified. Heterogeneity was minimal, and moderators were nonsignificant; results survived sensitivity tests, and no publication bias was identified. In non-ADHD comparison groups (k = 11, N = 335), white and pink noise had a negative effect (g = -0.212, 95% CI [-0.355, -0.069], p = .0036).

CONCLUSION

White and pink noise provide a small benefit on laboratory attention tasks for individuals with ADHD or high ADHD symptoms, but not for non-ADHD individuals. This article addresses theoretical implications, cautions, risks, and limitations.

PLAIN LANGUAGE SUMMARY

Public interest in the potential benefits of white, pink, and brown noise exposure for enhancing task performance for individuals with attention-deficit/hyperactivity disorder (ADHD) has increased substantially. This systematic review and meta-analysis included 13 studies with 335 participants and found that white/pink noise improved cognitive performance for children and young adults with ADHD or significant ADHD symptoms. In contrast, white/pink noise impaired cognitive performance for individuals without ADHD. Positive effects of noise were small, but these results point to a possible low-cost, low-risk intervention that may benefit youth with ADHD. Additional studies are needed to confirm effects and identify safe and appropriate decibel levels. The potential detrimental effects for individuals without ADHD also requires further study.

STUDY PREREGISTRATION INFORMATION

White Noise for ADHD: A Systematic Review And Meta-analysis; https://www.crd.york.ac.uk/prospero; CRD42023393992.

Autistic traits and speech perception in social and non-social noises

Individuals with the autism spectrum disorder (ASD) experience difficulties in perceiving speech in background noises with temporal dips; they also lack social orienting. We tested two hypotheses: (1) the higher the autistic traits, the lower the performance in the speech-in-noise test, and (2) individuals with high autistic traits experience greater difficulty in perceiving speech, especially in the non-vocal noise, because of their attentional bias toward non-vocal sounds. Thirty-eight female Japanese university students participated in an experiment measuring their ability to perceive speech in the presence of noise. Participants were asked to detect Japanese words embedded in vocal and non-vocal background noises with temporal dips. We found a marginally significant effect of autistic traits on speech perception performance, suggesting a trend that favors the first hypothesis. However, caution is needed in this interpretation because the null hypothesis is not rejected. No significant interaction was found between the types of background noise and autistic traits, indicating that the second hypothesis was not supported. This might be because individuals with high autistic traits in the general population have a weaker attentional bias toward non-vocal sounds than those with ASD or to the explicit instruction given to attend to the target speech.

Effects of auditory white noise stimulation on sustained attention and response time variability

Introduction

"The moderate brain arousal model" claims that white noise improves attention by optimizing brain arousal. We analyze Conners' Continuous Performance Test-3 (CCPT-3) performance, expecting to find reduced reaction time variability with noise mediated by decrease under long event-rates and in later parts of the test, indicating that noise reverse fall in phasic and tonic arousal.

Methods

Sixty-five children with high or lower ADHD-symptoms from a child psychiatric unit, succeeded to complete the CCPT-3 with and without white noise.

Results

Noise reduced overall variability, improved performance in later parts of the test, and reduced response variability under the longest event rate particularly in the high symptoms group. No overall change in omissions and commissions, but the high symptoms group made fewer omissions during noise compared the low symptom group.

Discussion

The study indicates an arousal effect of noise but should be replicated with other noise variants and amplitudes to improve effect and compliance.

Speech perception in noise, working memory, and attention in children: A scoping review

PURPOSE

Speech perception in noise is an everyday occurrence for adults and children alike. The factors that influence how well individuals cope with noise during spoken communication are not well understood, particularly in the case of children. This article aims to review the available evidence on how working memory and attention play a role in children's speech perception in noise, how characteristics of measures affect results, and how this relationship differs in non-typical populations.

METHOD

This article is a scoping review of the literature available on PubMed. Forty articles were included for meeting the inclusion criteria of including children as participants, some measure of speech perception in noise, some measure of attention and/or working memory, and some attempt to establish relationships between the measures. Findings were charted and presented keeping in mind how they relate to the research questions.

RESULTS

The majority of studies report that attention and especially working memory are involved in speech perception in noise by children. We provide an overview of the impact of certain task characteristics on findings across the literature, as well as how these affect non-typical populations.

CONCLUSION

While most of the work reviewed here provides evidence suggesting that working memory and attention are important abilities employed by children in overcoming the difficulties imposed by noise during spoken communication, methodological variability still prevents a clearer picture from emerging.

Auditory P3a response to native and foreign speech in children with or without attentional deficit

The aim of this study was to investigate the attentional mechanism in speech processing of native and foreign language in children with and without attentional deficit. For this purpose, the P3a component, cognitive neuromarker of the attentional processes, was investigated in a two-sequence two-deviant oddball paradigm using Finnish and English speech items via event-related potentials (ERP) technique. The difference waves reflected the temporal brain dynamics of the P3a response in native and foreign language contexts. Cluster-based permutation tests evaluated the group differences over the P3a time window. A correlation analysis was conducted between the P3a response and the attention score (ATTEX) to evaluate whether the behavioral assessment reflected the neural activity. The source reconstruction method (CLARA) was used to investigate the neural origins of the attentional differences between groups and conditions. The ERP results showed a larger P3a response in the group of children with attentional problems (AP) compared to controls (CTR). The P3a response differed statistically between the two groups in the native language processing, but not in the foreign language. The ATTEX score correlated with the P3a amplitude in the native language contrasts. The correlation analyses hint at some hemispheric brain activity difference in the frontal area. The group-level CLARA reconstruction showed activation in the speech perception and attention networks over the frontal, parietal, and temporal areas. Differences in activations of these networks were found between the groups and conditions, with the AP group showing higher activity in the source level, being the origin of the ERP enhancement observed on the scalp level.

The Effects of White Noise on Attentional Performance and On-Task Behaviors in Preschoolers with ADHD

Several models have tentatively associated improving attention-deficit/hyperactivity disorder (ADHD) symptoms with arousal and external environmental stimulation. In order to further clarify the relationships between ADHD symptoms, arousal, and external stimulation, this study focused on exploring the "simultaneous" effects of white noise on intrinsic attentional performance and extrinsic on-task behaviors in preschoolers with and without ADHD. By using the computerized task (K-CPT 2), 104 preschoolers, including 52 ADHD children and 52 typically developing (TD) children, were tested and analyzed for their intrinsic attention (such as detectability, omission errors, commission errors, and reaction time). Simultaneously, these preschoolers' external on-task behaviors were recorded for analysis through systematic observation. This study showed that white noise could effectively improve attention performance, including enhancing the ability to differentiate non-targets from targets and decreasing omission errors. It could also reduce the extrinsic hyperactive behaviors of preschoolers with ADHD. The findings of this study highlighted that white noise stimulation is a beneficial non-pharmacological treatment for preschoolers with ADHD. In contrast, for TD preschoolers, the results of this study showed that the external white noise stimuli were not only unhelpful but also a burden.

Listening to White Noise Improved Verbal Working Memory in Children with Attention-Deficit/Hyperactivity Disorder: A Pilot Study

Existing research demonstrates that children with attention-deficit/hyperactivity disorder (ADHD) underperform in cognitive tasks involving working memory (WM) due to hypo-arousal, which has led to the development of arousal regulation models to determine proper levels of arousal and optimal cognitive outcomes. The present study focuses on investigating the effects of external auditory stimuli on verbal WM in children with ADHD. Thirteen children with ADHD (aged 6–10 years old) and thirteen age- and gender-matched children with typical development (TD) completed the verbal WM task when listening to no sound, white noise, or pleasant music. A two-way repeated-measures analysis of variance was used to compare the verbal WM performance between groups in the three auditory conditions. Children with ADHD showed the best verbal WM performance when listening to white noise and the worst performance when listening to no sound. Yet, children with TD performed the best in the no-sound condition and the worst in the white noise condition. Our findings suggest auditory white noise is beneficial for ideal arousal regulation and cognitive performance involving verbal WM for children with ADHD and support the moderate brain arousal model. Providing external white noise is a non-invasive and cost-effective approach to improving verbal WM in children with ADHD in real-world contexts.

Linguistic Complexity of Speech Recognition Test Sentences and Its Influence on Children's Verbal Repetition Accuracy

OBJECTIVES

Speech recognition (SR)-tests have been developed for children without considering the linguistic complexity of the sentences used. However, linguistic complexity is hypothesized to influence correct sentence repetition. The aim of this study is to identify lexical and grammatical parameters influencing verbal repetition accuracy of sentences derived from a Dutch SR-test when performed by 6-year-old typically developing children.

DESIGN

For this observational, cross-sectional study, 40 typically developing children aged 6 were recruited at four primary schools in the Netherlands. All children performed a sentence repetition task derived from an SR-test for adults. The sentence complexity was described beforehand with one lexical parameter, age of acquisition, and four grammatical parameters, specifically sentence length, prepositions, sentence structure, and verb inflection. A multiple logistic regression analysis was performed.

RESULTS

Sentences with a higher age of acquisition (odds ratio [OR] = 1.59) or greater sentence length (OR = 1.28) had a higher risk of repetition inaccuracy. Sentences including a spatial (OR = 1.25) or other preposition (OR = 1.25) were at increased risk for incorrect repetition, as were complex sentences (OR = 1.69) and sentences in the present perfect (OR = 1.44) or future tense (OR = 2.32).

CONCLUSIONS

The variation in verbal repetition accuracy in 6-year-old children is significantly influenced by both lexical and grammatical parameters. Linguistic complexity is an important factor to take into account when assessing speech intelligibility in children.

Sensory white noise improves reading skills and memory recall in children with reading disability

BACKGROUND

Reading disability (RD) is characterized by slow and inaccurate word reading development, commonly reflecting underlying phonological problems. We have previously shown that exposure to white noise acutely improves cognitive performance in children with ADHD. The question addressed here is whether white noise exposure yields positive outcomes also for RD. There are theoretical reasons to expect such a possibility: a) RD and ADHD are two overlapping neurodevelopmental disorders and b) since prior research on white noise benefits has suggested that a central mechanism might be the phenomenon of stochastic resonance, then adding certain kinds of white noise might strengthen the signal-to-noise ratio during phonological processing and phoneme-grapheme mapping.

METHODS

The study was conducted with a group of 30 children with RD and phonological decoding difficulties and two comparison groups: one consisting of skilled readers (n = 22) and another of children with mild orthographic reading problems and age adequate phonological decoding (n = 30). White noise was presented experimentally in visual and auditory modalities, while the children performed tests of single word reading, orthographic word recognition, nonword reading, and memory recall.

RESULTS

For the first time, we show that visual and auditory white noise exposure improves some reading and memory capacities "on the fly" in children with RD and phonological decoding difficulties. By contrast, the comparison groups displayed either no benefit or a gradual decrease in performance with increasing noise. In interviews, we also found that the white noise exposure was tolerable or even preferred by many children.

CONCLUSION

These novel findings suggest that poor readers with phonological decoding difficulties may be immediately helped by white noise during reading. Future research is needed to determine the robustness, mechanisms, and long-term practical implications of the white noise benefits in children with reading disabilities.

Effects of white noise on word recall performance and brain activity in healthy adolescents with normal and low auditory working memory

The present study examined the impact of white noise on word recall performance and brain activity in 40 healthy adolescents, split in two groups (normal and low) depending on their auditory working memory capacity (AWMC). Using functional magnetic resonance imaging, participants performed a backward recall task under four different signal-to-noise ratio (SNR) conditions: 15, 10, 5, and 0-dB SNR. Behaviorally, normal AWMC individuals scored significantly higher than low AWMC individuals across noise levels. Whole-brain analyses showed brain activation not to be statistically different between groups across noise levels. In the normal group, a significant positive relationship was found between performance and number of activated voxels in the right superior frontal gyrus. In the low group, significant positive correlations were found between performance and number of activated voxels in left superior frontal gyrus, left inferior frontal gyrus, and left anterior cingulate cortex. These findings suggest that the strategic structure involved in the enhancement of AWM performance may differ in normal and low AWMC individuals.

Can auditory warning signals normalize eye movements in children with ADHD?

Attenuated baseline arousal has been hypothesized to underlie symptoms of attention deficit/hyperactivity disorder (ADHD). A behavioral signature of reduced baseline arousal is an increased beneficiary effect of warning signals in reaction tasks. This paradoxical effect is believed to be caused by a temporary increase in arousal induced by warning signals. In a preregistered study, we tested the hypothesis that children with high levels of ADHD symptoms would be hyperresponsive to warning signals in a well-established visual attention task (the gap/overlap paradigm). Previous studies using this task have found slower and more variable saccadic reaction times in children with ADHD compared to typically developing children, suggesting that these eye movement metrics are candidate biomarkers. We examined 71 children, of which 1/3 had a diagnosis of ADHD, using both dimensional analyses and group comparisons. Previously reported findings of reduced saccadic latency and increased latency variability were replicated. Importantly, saccadic latency was normalized by auditory warning signals. Analyses of pupil dilation, a physiological index of arousal and locus coeruleus-noradrenergic activity, confirmed that warning signals led to enhanced arousal. Our findings are novel and contribute to our understanding of arousal and attention in ADHD and have implications for treatment and interventions.

Listening Effort Among Adults With and Without Attention-Deficit/Hyperactivity Disorder

Purpose Few studies have assessed listening effort (LE)-the cognitive resources required to perceive speech-among populations with intact hearing but reduced availability of cognitive resources. Attention/deficit/hyperactivity disorder (ADHD) is theorized to restrict attention span, possibly making speech perception in adverse conditions more challenging. This study examined the effect of ADHD on LE among adults using a behavioral dual-task paradigm (DTP). Method Thirty-nine normal-hearing adults (aged 21-27 years) participated: 19 with ADHD (ADHD group) and 20 without ADHD (control group). Baseline group differences were measured in visual and auditory attention as well as speech perception. LE using DTP was assessed as the performance difference on a visual-motor task versus a simultaneous auditory and visual-motor task. Results Group differences in attention were confirmed by differences in visual attention (larger reaction times between congruent and incongruent conditions) and auditory attention (lower accuracy in the presence of distractors) among the ADHD group, compared to the controls. LE was greater among the ADHD group than the control group. Nevertheless, no group differences were found in speech perception. Conclusions LE is increased among those with ADHD. As a DTP assumes limited cognitive capacity to allocate attentional resources, LE among those with ADHD may be increased because higher level cognitive processes are more taxed in this population. Studies on LE using a DTP should take into consideration mechanisms of selective and divided attention. Among young adults who need to continuously process great volumes of auditory and visual information, much more effort may be expended by those with ADHD than those without it. As a result, those with ADHD may be more prone to fatigue and irritability, similar to those who are engaged in more outwardly demanding tasks.

Speech Processing Difficulties in Attention Deficit Hyperactivity Disorder

The large body of research that forms the ease of language understanding (ELU) model emphasizes the important contribution of cognitive processes when listening to speech in adverse conditions; however, speech-in-noise (SIN) processing is yet to be thoroughly tested in populations with cognitive deficits. The purpose of the current study was to contribute to the field in this regard by assessing SIN performance in a sample of adolescents with attention deficit hyperactivity disorder (ADHD) and comparing results with age-matched controls. This population was chosen because core symptoms of ADHD include developmental deficits in cognitive control and working memory capacity and because these top-down processes are thought to reach maturity during adolescence in individuals with typical development. The study utilized natural language sentence materials under experimental conditions that manipulated the dependency on cognitive mechanisms in varying degrees. In addition, participants were tested on cognitive capacity measures of complex working memory-span, selective attention, and lexical access. Primary findings were in support of the ELU-model. Age was shown to significantly covary with SIN performance, and after controlling for age, ADHD participants demonstrated greater difficulty than controls with the experimental manipulations. In addition, overall SIN performance was strongly predicted by individual differences in cognitive capacity. Taken together, the results highlight the general disadvantage persons with deficient cognitive capacity have when attending to speech in typically noisy listening environments. Furthermore, the consistently poorer performance observed in the ADHD group suggests that auditory processing tasks designed to tax attention and working memory capacity may prove to be beneficial clinical instruments when diagnosing ADHD.

Deficits in auditory sensory discrimination among children with attention-deficit/hyperactivity disorder

Research into children with attention-deficit/hyperactivity disorder (ADHD) has focused on complex cognitive dysfunction, but less attention has been paid to sensory perception processes underlying the symptoms of ADHD. Based on signal detection theory, the present study compared the sensory discrimination ability and decision bias of children with and without ADHD. It also investigated the differences between ADHD with predominantly inattentive (ADHDi) and combined presentations (ADHDc). The sample of 75 children and adolescents with ADHD (24 ADHDi, 51 ADHDc) (16 females and 59 males) and 22 typical developing controls (TD) (8 females and 14 males) completed an auditory signal detection task. Participants were asked to detect signals against levels of transient background noise (35, 45, 55, and 65 dB). The results showed that with the increase of noise levels, both the ADHD and TD groups demonstrated decreased sensory discrimination. Although both groups successfully detected signal against noise levels from 35 to 55 dB, the ADHD group showed lower discrimination ability than that of the TD group. For decision bias, no group difference was found. Further comparisons regarding the predominant symptom presentation of ADHD sub-groups showed no differences. Current research has suggested that the deficit in ADHD people's signal detection performance can be attributed to sensory discrimination rather than decision bias. We suggest that background noise should be taken into account when using auditory stimuli to investigate cognitive functions in people with ADHD.

White noise enhances new-word learning in healthy adults

Research suggests that listening to white noise may improve some aspects of cognitive performance in individuals with lower attention. This study investigated the impact of white noise on new word learning in healthy young adults, and whether this effect was mediated by executive attention skills. Eighty participants completed a single training session to learn the names of twenty novel objects. The session comprised 5 learning phases, each followed by a recall test. A final recognition test was also administered. Half the participants listened to white noise during the learning phases, and half completed the learning in silence. The noise group demonstrated superior recall accuracy over time, which was not impacted by participant attentional capacity. Recognition accuracy was near ceiling for both groups. These findings suggest that white noise has the capacity to enhance lexical acquisition.

Perception in attention deficit hyperactivity disorder

A large body of research demonstrated that individuals with attention deficit hyperactivity disorder (ADHD) suffer from various neuropsychological deficits. In contrast, less is known and only divergent evidence exists on perceptual functions of individuals with ADHD. This is problematic as neuropsychological and perceptual functions are closely interrelated and are often difficult to disentangle in behavioral assessments. This study presents the conduct and results of a systematic literature review on perceptual functions in children and adults with ADHD. This review considers studies using psychophysical methods (objective measurements) and self- and informant reports (subjective measurements). Results indicate that individuals with ADHD have altered perceptual functions in various domains as compared to typically developing individuals. Increased perceptual functions in individuals with ADHD were found with regard to olfactory detection thresholds, whereas reduced perceptual functions were evident for aspects of visual and speech perception. Moreover, individuals with ADHD were found to experience discomfort to sensory stimuli at a lower level than typically developing individuals. Alterations of perceptual functions in individuals with ADHD were shown to be moderated by various factors, such as pharmacological treatment, cognitive functions, and symptom severity. We conclude by giving implications for daily life functioning and clinical practice.

Comparing Auditory Noise Treatment with Stimulant Medication on Cognitive Task Performance in Children with Attention Deficit Hyperactivity Disorder: Results from a Pilot Study

Background: Recent research has shown that acoustic white noise (80 dB) can improve task performance in people with attention deficits and/or Attention Deficit Hyperactivity Disorder (ADHD). This is attributed to the phenomenon of stochastic resonance in which a certain amount of noise can improve performance in a brain that is not working at its optimum. We compare here the effect of noise exposure with the effect of stimulant medication on cognitive task performance in ADHD. The aim of the present study was to compare the effects of auditory noise exposure with stimulant medication for ADHD children on a cognitive test battery. A group of typically developed children (TDC) took the same tests as a comparison.

Methods: Twenty children with ADHD of combined or inattentive subtypes and twenty TDC matched for age and gender performed three different tests (word recall, spanboard and n-back task) during exposure to white noise (80 dB) and in a silent condition. The ADHD children were tested with and without central stimulant medication.

Results: In the spanboard- and the word recall tasks, but not in the 2-back task, white noise exposure led to significant improvements for both non-medicated and medicated ADHD children. No significant effects of medication were found on any of the three tasks.

Conclusion: This pilot study shows that exposure to white noise resulted in a task improvement that was larger than the one with stimulant medication thus opening up the possibility of using auditory noise as an alternative, non-pharmacological treatment of cognitive ADHD symptoms.