Auditory Memory Task Research Articles

Overgeneralization of autonomic defensive reactions in obesity

Generalizing defensive responses to new stimuli resembling learned threats is an adaptive process within an ever-changing environment. However, evaluation mechanisms excessively biased toward generalization (i.e., overgeneralization) may underlie anxiety-related symptoms. In the context of obesity, fear memory and fear generalization processes have never been investigated. In this study, participants with obesity and healthy participants as controls underwent a single-cue auditory fear conditioning paradigm and recognition memory tasks. We analyzed the autonomic reactions evoked by threat-predictive and new stimuli, as well as the recognition performance towards the same cues. We found that participants with obesity displayed similar autonomic defensive responses to a learned fearful stimulus, but enhanced reactions to new stimuli, when compared with the controls. We detected no significant differences between groups in recognition abilities. Our results provided the first evidence that obesity may widen fear generalization patterns. This alteration may encourage future research in investigating the link between emotional dysregulation and clinical anxiety-related symptoms in obesity.

Introducing ART: A new method for testing auditory memory with circular reproduction tasks.

Theories of visual working memory have seen significant progress through the use of continuous reproduction tasks. However, these tasks have mainly focused on studying visual features, with limited examples existing in the auditory domain. Therefore, it is unknown to what extent newly developed memory models reflect domain-general limitations or are specific to the visual domain. To address this gap, we developed a novel methodology: the Auditory Reproduction Task (ART). This task utilizes Shepard tones, which create an infinite rising or falling tone illusion by dissecting pitch chroma and height, to create a 1-360° auditory circular space. In Experiment 1, we validated the perceptual circularity and uniformity of this auditory stimulus space. In Experiment 2, we demonstrated that auditory working memory shows similar set size effects to visual working memory-report error increased at a set size of 2 relative to 1, caused by swap errors. In Experiment 3, we tested the validity of ART by correlating reproduction errors with commonly used auditory and visual working memory tasks. Analyses revealed that ART errors were significantly correlated with performance in both auditory and visual working memory tasks, albeit with a stronger correlation observed with auditory working memory. While these experiments have only scratched the surface of the theoretical and computational constraints on auditory working memory, they provide a valuable proof of concept for ART. Further research with ART has the potential to deepen our understanding of auditory working memory, as well as to explore the extent to which existing models are tapping into domain-general constraints.

Surgical outcomes in children with drug-resistant epilepsy and hippocampal sclerosis

BackgroundHippocampal sclerosis (HS) is a common surgical substrate in adult epilepsy surgery cohorts but variably reported in various pediatric cohorts. ObjectiveWe aimed to study the epilepsy phenotype, radiological and pathological variability, seizure and neurocognitive outcomes in children with drug-resistant epilepsy and hippocampal sclerosis (HS) with or without additional subtle signal changes in anterior temporal lobe who underwent surgery. MethodsThis retrospective study enrolled children with drug-resistant focal epilepsy and hippocampal sclerosis with or without additional subtle T2-Fluid Attenuated Inversion Recovery (FLAR)/Proton Density (PD) signal changes in anterior temporal lobe who underwent anterior temporal lobectomy with amygdalohippocampectomy. Their clinical, EEG, neuropsychological, radiological and pathological data were reviewed and summarized. ResultsThirty-six eligible patients were identified. The mean age at seizure onset was 3.7 years; 25% had daily seizures at time of surgery. Isolated HS was noted in 22 (61.1%) cases and additional subtle signal changes in ipsilateral temporal lobe in 14 (38.9%) cases. Compared to the normative population, the group mean performance in intellectual functioning and most auditory and visual memory tasks were significantly lower than the normative sample. The mean age at surgery was 12.3 years; 22 patients (61.1%) had left hemispheric surgeries. ILAE class 1 outcomes was seen in 28 (77.8%) patients after a mean follow up duration of 2.3 years. Hippocampal sclerosis was noted pathologically in 32 (88.9%) cases; type 2 (54.5%) was predominant subtype where further classification was possible. Additional pathological abnormalities were seen in 11 cases (30.6%); these had had similar rates of seizure freedom as compared to children with isolated hippocampal sclerosis/gliosis (63.6% vs 84%, p=0.21). Significant reliable changes were observed across auditory and visual memory tasks at an individual level post surgery. ConclusionsFavourable seizure outcomes were seen in most children with isolated radiological hippocampal sclerosis. Patients with additional pathological abnormalities had similar rates of seizure freedom as compared to children with isolated hippocampal sclerosis/gliosis.

Unifying network model links recency and central tendency biases in working memory

The central tendency bias, or contraction bias, is a phenomenon where the judgment of the magnitude of items held in working memory appears to be biased toward the average of past observations. It is assumed to be an optimal strategy by the brain and commonly thought of as an expression of the brain’s ability to learn the statistical structure of sensory input. On the other hand, recency biases such as serial dependence are also commonly observed and are thought to reflect the content of working memory. Recent results from an auditory delayed comparison task in rats suggest that both biases may be more related than previously thought: when the posterior parietal cortex (PPC) was silenced, both short-term and contraction biases were reduced. By proposing a model of the circuit that may be involved in generating the behavior, we show that a volatile working memory content susceptible to shifting to the past sensory experience – producing short-term sensory history biases – naturally leads to contraction bias. The errors, occurring at the level of individual trials, are sampled from the full distribution of the stimuli and are not due to a gradual shift of the memory toward the sensory distribution’s mean. Our results are consistent with a broad set of behavioral findings and provide predictions of performance across different stimulus distributions and timings, delay intervals, as well as neuronal dynamics in putative working memory areas. Finally, we validate our model by performing a set of human psychophysics experiments of an auditory parametric working memory task.

Unifying network model links recency and central tendency biases in working memory.

The central tendency bias, or contraction bias, is a phenomenon where the judgment of the magnitude of items held in working memory appears to be biased toward the average of past observations. It is assumed to be an optimal strategy by the brain and commonly thought of as an expression of the brain's ability to learn the statistical structure of sensory input. On the other hand, recency biases such as serial dependence are also commonly observed and are thought to reflect the content of working memory. Recent results from an auditory delayed comparison task in rats suggest that both biases may be more related than previously thought: when the posterior parietal cortex (PPC) was silenced, both short-term and contraction biases were reduced. By proposing a model of the circuit that may be involved in generating the behavior, we show that a volatile working memory content susceptible to shifting to the past sensory experience - producing short-term sensory history biases - naturally leads to contraction bias. The errors, occurring at the level of individual trials, are sampled from the full distribution of the stimuli and are not due to a gradual shift of the memory toward the sensory distribution's mean. Our results are consistent with a broad set of behavioral findings and provide predictions of performance across different stimulus distributions and timings, delay intervals, as well as neuronal dynamics in putative working memory areas. Finally, we validate our model by performing a set of human psychophysics experiments of an auditory parametric working memory task.

Functional coupling between auditory memory and verbal transformations

The ability to parse sound mixtures into coherent auditory objects is fundamental to cognitive functions, such as speech comprehension and language acquisition. Yet, we still lack a clear understanding of how auditory objects are formed. To address this question, we studied a speech-specific case of perceptual multistability, called verbal transformations (VTs), in which a variety of verbal forms is induced by continuous repetition of a physically unchanging word. Here, we investigated the degree to which auditory memory through sensory adaptation influences VTs. Specifically, we hypothesized that when memory persistence is longer, participants are able to retain the current verbal form longer, resulting in sensory adaptation, which in turn, affects auditory perception. Participants performed VT and auditory memory tasks on different days. In the VT task, Japanese participants continuously reported their perception while listening to a Japanese word (2- or 3-mora in length) played repeatedly for 5 min. In the auditory memory task, a different sequence of three morae, e.g., /ka/, /hi/, and /su/, was presented to each ear simultaneously. After some period (0–4 s), participants were visually cued to recall one of the sequences, i.e., in the left or right ear. We found that delayed recall accuracy was negatively correlated with the number of VTs, particularly under 2-mora conditions. This suggests that memory persistence is important for formation and selection of perceptual objects.

The dynamics of auditory working memory impairment in logopenic aphasia and Alzheimer’s disease

AbstractBackgroundImpaired auditory verbal working memory is a diagnostic hallmark and integral driver of the clinical phenotype in logopenic aphasia. However, the physiology of the working memory buffer in this syndrome is poorly characterised. Here we addressed the temporal dynamics of auditory verbal working memory in patients with logopenic aphasia and typical Alzheimer’s disease.MethodIn a cohort of patients with logopenic aphasia and typical Alzheimer’s disease and in healthy age‐matched controls, we assessed how temporal manipulations of standard auditory verbal working memory tasks (forward and reverse digit span and phrasal repetition) affected performance. We varied tempo of delivery and inter‐trial gap and performed a detailed analysis of error types. Participants also had pure tone audiometry to assess peripheral hearing function and a comprehensive general neuropsychological assessment.ResultCompared with healthy controls, patients with logopenic aphasia and Alzheimer’s disease showed increased sensitivity to temporal manipulation of auditory verbal working memory tasks and error profiles suggesting a dynamic physiological lesion of the working memory buffer. These effects were particularly marked in the logopenic group.ConclusionOur findings open a novel physiological window on working memory dynamics in Alzheimer’s disease syndromes. Further work is warranted to assess how this dynamic deficit impacts communication in patients’ daily lives, how it can best inform management interventions and its potential as a novel, rapid read‐out of neural function in the era of disease‐modifying therapies.

Cognitive load enhances patience rather than impulsivity.

Previous studies on the impact of cognitive load on time preference has led to conflicting results. However, these studies either failed to consider response randomness while analyzing behavioral data or involved a defective control level for a clear conclusion regarding the impacts of cognitive load. With two experiments using an adaptive approach to generating appropriate individual-specific stimuli and an additional, preregistered partial replication study, the current research provided consistent evidence that imposing cognitive load with a 2-back auditory memory task would produce simultaneously more patient and more random intertemporal choices. The finding of changed time preference was at odds with the dual-process account thereof but provided clear support for the role of reduced time sensitivity in intertemporal choices under cognitive load. Results of relevant model comparison did not support an account built upon more usage of heuristic strategies under cognitive load, either. Future research could examine boundary conditions for the dual-process and time-sensitivity accounts of time preference such as task features and individual characteristics that moderate the impact of cognitive load on time preference.

Effects of different cognitive functions on acoustic voice parameters in young adults

Objectives: The aim of this study was to investigate the effect of different cognitive functions on acoustic voice parameters by recording the use of cognitive functions during extended /a/ phonation in young adults. Patients and Methods: This study was conducted with a total of 31 participants (8 males, 23 females, mean age: 22.3±1.1 years; range, 18 to 30 years) between June 14, 2023 and August 23, 2023. The mean fundamental frequency (F0), jitter (local), jitter (rap), shimmer (local), shimmer dB, and mean harmonics-to-noise ratio values were analyzed as acoustic voice parameters in a total of 186 voice recordings taken in six tasks, including normal and other five tasks (visual attention, language, auditory memory, visual memory, and working memory). Results: A statistically significant difference was found between the acoustic parameters of the six tasks (p<0.001). Shimmer dB showed a statistically significant difference between the auditory memory task and normal state, visual attention and normal state, and working memory and normal state (p<0.05). Conclusion: Different cognitive functions, especially auditory memory, visual attention, and working memory, may have an effect on acoustic voice parameters. Therefore, cognitive functions can be evaluated to identify deficiencies in the relevant cognitive area, and working on these cognitive functions together with voice therapy may shorten the therapy process.

Performances of Pointing Phonological Memory Tasks between Children with and without Speech Sound Disorders

Objectives: A new phonological memory task using pointing responses was developed and the performance of each sub-task was compared between children with and without speech sound disorders (SSD). Methods: 16 children with SSD and 14 typically developing children (TD) performed pointing memory tasks, which consists of four sub-tasks—auditory short-term, auditory working, visual short-term, and visual working memory; and performances between groups and between each sub-task were compared. In addition, the correlation between the new task and the existing task (digit span task), vocabulary sizes and the accuracy of consonants was analyzed. Results: First, the SSD group showed significantly lower performance in the pointing memory tasks than the TD group. Second, both the SSD and TD groups showed significantly higher performance in auditory stimulation compared with visual stimulation, and in short-term memory than working memory. Third, in the case of the TD group, the performance of the auditory short-term memory task was much better, and there were no significant differences among the other three sub-tasks, while the SSD group showed a sequential decline in performances among the four sub-tasks. Finally, there was a high correlation between the new task and the existing task, vocabulary sizes, and the accuracy of consonants. Conclusion: The low performance in the phonological memory task of the SSD group is not due to weakness in articulation or in auditory processing, but to defects in phonological short-term/working memory itself. The results of this study provide meaningful information on the different performance patterns of phonological memory tasks according to stimulus modalities between the SSD and TD groups.

Non-arbitrary mappings between size and sound of English words: Form typicality effects during lexical access and memory.

A century of research has provided evidence of limited size sound symbolism in English, that is, certain vowels are non-arbitrarily associated with words denoting small versus large referents (e.g., /i/ as in teensy and /ɑ/ as in tall). In the present study, we investigated more extensive statistical regularities between surface form properties of English words and ratings of their semantic size, that is, form typicality, and its impact on language and memory processing. Our findings provide the first evidence of significant word form typicality for semantic size. In five empirical studies using behavioural megastudy data sets of performance on written and auditory lexical decision, reading aloud, semantic decision, and recognition memory tasks, we show that form typicality for size is a stronger and more consistent predictor of lexical access during word comprehension and production than semantic size, in addition to playing a significant role in verbal memory. The empirical results demonstrate that statistical information about non-arbitrary form-size mappings is accessed automatically during language and verbal memory processing, unlike semantic size that is largely dependent on task contexts that explicitly require participants to access size knowledge. We discuss how a priori knowledge about non-arbitrary form-meaning associations in the lexicon might be incorporated in models of language processing that implement Bayesian statistical inference.

Evaluating compliance on a gamified auditory training task in Veterans

Service members and Veterans are regularly exposed to environmental factors that have been shown to contribute to hearing deficits. These listening deficits may present as auditory processing complaints such as difficulty listening in background noise in the absence of a peripheral hearing loss. The public app, Listen: An Auditory Training Experience, developed by University of California Riverside Brain Game Center, aims to improve overall speech comprehension by targeting skills related to spectro-temporal modulations, spatialized sound cues, and auditory memory tasks. Ten Veterans participated in a two-week gamified auditory training program. Compliance on the auditory training tasks was assessed by monitoring the number of trials accomplished each day, accuracy above chance, reaction time, and improvements in performance over time. Improvements were also monitored for untrained auditory tasks, such as speech-in-noise performance and a battery of central auditory processing assessments.

Lighting color temperature impacts effort-related cardiovascular response to an auditory short-term memory task

To better understand the impact of environmental light on processes that underlie cognitive activity, Lasauskaite and Cajochen (2018) recently proposed a theoretical model that predicts how light's correlated color temperature (CCT) affects effort. Here we tested whether the effects of CCT of light on effort-related cardiovascular response also extend to another sensory input—hearing. In two experimental blocks, participants were exposed to either low (2800 K) or high correlated color temperature (6500 K) light with an illumination level of 500 lux for 15 min before and while they performed an auditory n-back task varying in difficulty level (low difficulty/1-back vs. moderate difficulty/2-back). Mental effort was indexed as sympathetic beta-adrenergic impact on the heart, measured via cardiac pre-ejection period and systolic blood pressure. Based on the theoretical model, we hypothesized that light with a high CCT should lead to lower mental effort compared to light with a low CCT in both the low and moderate task difficulty conditions. Moreover, moderate task difficulty should lead to stronger effort compared to an easy task. The results did not show expected differences in invested effort levels between the task difficulty conditions (1-back vs. 2-back task) measured by cardiac pre-ejection period and systolic blood pressure. However, in line with our prediction, the results indicated that higher CCT of light decreased effort during an auditory memory task. Task performance was higher in easy than moderate task difficulty but was not altered by lighting conditions. Furthermore, we found no significant associations between cardiovascular reactivity and changes in mood, sleepiness, light, task, or effort ratings. Taken together, our results provide first evidence that higher CCT of light reduces the amount of effort invested during cognitive tasks for which hearing is needed. Given that this study was conducted under controlled laboratory conditions and with healthy young participants, additional research is needed to demonstrate that our results generalize to real-life applications. Nevertheless, we recommend that lower CCT of light should be avoided in learning and work contexts, as it might lead to higher effort and cardiovascular reactivity that may contribute to the development of cardiovascular health problems. Instead, we recommend higher CCT of light during daytime for wellbeing and health.

Cross-task cognitive workload recognition using a dynamic residual network with attention mechanism based on neurophysiological signals

Background and ObjectiveEvaluation of human cognitive workload (CW) helps improve the user experience of human-centered systems. To provide a continuous estimation of the CW, we built a CW recognizer that maps human electroencephalograms (EEGs) to discrete CW levels with deep learning tools. However, the EEG distribution varies when humans perform different cognitive tasks. There is thus a question on the capacity for generalizing the CW recognizer across tasks. In this study, we examined the CW's performance when it was trained and tested on two EEG databases corresponding to different human-machine tasks. MethodsA novel deep neural network-based EEG recognizer, dynamic residual network with attention mechanism (DRNA-Net), is proposed in the present study. By taking advantage of recurrent networks, the DRNA-Net further incorporates a self-attention mechanism in discovering robust EEG patterns across different cognitive tasks. ResultsWe designed an experiment that applied a multidimensional N-back task to induce the CW that consists of visual and auditory memory tasks. We validated the cross-task generalization capability of the DRNA-Net based on the EEG features extracted from the N-back task and a public database. The results show that the DRNA-Net achieves classification accuracy and Macro-F1 values are 0.6055 and 0.6067, respectively. ConclusionsThe performance of the DRNA-Net indicates that it has a certain ability of cross-task cognitive workload classification, which outperforms several shallow learners and deep convolutional neural networks under various conditions of the feature subsets.

Language and Neurocognitive Impairments Associated with Hypothyroidism

Introduction: Accumulating clinical evidence has indicated that hypothyroidism was associated with neurocognitive and linguistic impairments; however, these impairments were not reported in Arabic individuals. The aims of the present study were (1) to investigate the patterns of linguistic and neurocognitive impairments associated with hypothyroidism in native speakers of Jordanian Arabic and (2) to examine the accuracy of TFT in confirming a clinical diagnosis of hypothyroidism. Methods: A cross-sectional design with random recruitment of participants from targeted hypothyroid (HT) and euthyroid (ET) groups was conducted. Clinical evaluation of hypothyroidism was obtained via a structured questionnaire followed by TFT. Evaluation measures included digit span, confrontation naming, color naming, auditory and visual memory, and visual recognition tasks. The HT group comprised 36 participants including 8 males and 28 females with a ratio of 1:3.5. Their age ranged between 5.11 and 10.7 years (M = 7.7, SD = ±1.4). The ET group included an equal number of participants in terms of age and gender, their age ranged between 5.9 and 10.8 years (M = 7.6, SD = ±1.5). Results: Results revealed significant differences between the two experimental groups in all of the linguistic and neurocognitive tasks. The HT showed 10- and 26-s delayed responses on a timed color naming and visual recognition tasks compared to the ET group, whereas the ET group showed larger scores compared to the HT on the digit span, confrontation naming, auditory memory, and visual memory tasks. Differences were 2.2, 4, 1.7, and 3 points, respectively. Conclusion: Hypothyroidism influences linguistic and neurocognitive functions mainly naming ability, working memory, and auditory and visual processes needed for learning. Clinicians ought to be attentive to these impacts when designing screening and therapy protocols for children with hypothyroidism. Furthermore, TSH showed higher prediction of hypothyroidism and may be used in favor of FT3 and FT4.

Language aptitude in the visuospatial modality: L2 British Sign Language acquisition and cognitive skills in British Sign Language-English interpreting students.

Sign language interpreting (SLI) is a cognitively challenging task performed mostly by second language learners (i.e., not raised using a sign language as a home language). SLI students must first gain language fluency in a new visuospatial modality and then move between spoken and signed modalities as they interpret. As a result, many students plateau before reaching working fluency, and SLI training program drop-out rates are high. However, we know little about the requisite skills to become a successful interpreter: the few existing studies investigating SLI aptitude in terms of linguistic and cognitive skills lack baseline measures. Here we report a 3-year exploratory longitudinal skills assessments study with British Sign Language (BSL)-English SLI students at two universities (n = 33). Our aims were two-fold: first, to better understand the prerequisite skills that lead to successful SLI outcomes; second, to better understand how signing and interpreting skills impact other aspects of cognition. A battery of tasks was completed at four time points to assess skills, including but not limited to: multimodal and unimodal working memory, 2-dimensional and 3-dimensional mental rotation (MR), and English comprehension. Dependent measures were BSL and SLI course grades, BSL reproduction tests, and consecutive SLI tasks. Results reveal that initial BSL proficiency and 2D-MR were associated with selection for the degree program, while visuospatial working memory was linked to continuing with the program. 3D-MR improved throughout the degree, alongside some limited gains in auditory, visuospatial, and multimodal working memory tasks. Visuospatial working memory and MR were the skills closest associated with BSL and SLI outcomes, particularly those tasks involving sign language production, thus, highlighting the importance of cognition related to the visuospatial modality. These preliminary data will inform SLI training programs, from applicant selection to curriculum design.

Home-Based Electronic Cognitive Therapy in Patients With Alzheimer Disease: Feasibility Randomized Controlled Trial.

BackgroundCan home-based computerized cognitive training programs be a useful tool to sustain cognition and quality of life in patients with Alzheimer disease (AD)? To date, the progressive nature of the disease has made this question difficult to answer. Computerized platforms provide more accessibility to cognitive trainings; however, the feasibility of long-term, home-based computerized programs for patients with AD dementia remains unclear.ObjectiveWe aimed to investigate the feasibility of a 24-week home-based intervention program using the Constant Therapy app and its preliminary efficacy on cognition in patients with AD. Constant Therapy is a program developed for patients with speech and cognitive deficits. We hypothesized that patients with AD would use Constant Therapy daily over the course of the 24-week period.MethodsData were collected over a 48-week period. We recruited participants aged between 50 and 90 years with a diagnosis of mild cognitive impairment due to AD or mild AD dementia. Participants were randomly assigned to either the Constant Therapy (n=10) or active control (n=9) group. The Constant Therapy group completed a tablet-based training during the first 24 weeks; the second 24 weeks of computerized training were optional. The active control group completed paper-and-pencil games during the first 24 weeks and were invited to complete an optional Constant Therapy training during the second 24 weeks. Every 6 weeks, the participants completed the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). The participants independently accessed Constant Therapy using an Apple iPad. Our primary feasibility outcomes were the rate of adherence and daily use of Constant Therapy over 24 weeks. Our secondary outcomes were Constant Therapy performance over 24 weeks and change in RBANS scores between the 2 experimental groups.ResultsFeasibility analyses were computed for participants who completed 24 weeks of Constant Therapy. We found that long-term use of the Constant Therapy program was feasible in patients with AD over 24 weeks (adherence 80%; program use 121/168 days, for 32 minutes daily). These participants showed an overall improvement in accuracy and latency (P=.005) in the Constant Therapy scores, as well as specific improvements in visual and auditory memory, attention, and arithmetic tasks. The Constant Therapy group showed improvement in the RBANS coding subtest. No unexpected problems or adverse events were observed.ConclusionsLong-term (eg, 24 weeks) computerized cognitive training using Constant Therapy is feasible in patients with AD in the mild cognitive impairment and mild dementia stages. Patients adhered more to Constant Therapy than to the paper-and-pencil training over 24 weeks and improved their performance over time. These findings support the development of future randomized controlled trials that will investigate the efficacy of Constant Therapy to sustain cognitive function in patients with AD.Trial RegistrationClinicalTrials.gov NCT02521558; https://clinicaltrials.gov/ct2/show/NCT02521558

The Effect of Emotional Valence on Auditory Word Recognition Memory in English as a Foreign Language.

The present study investigated the effect of emotional valence on auditory word recognition memory in English as a foreign language. Participants included 48 native Spanish speakers whose foreign language was English. They viewed four emotionally negative, four positive, and four neutral videos that, in total, contained 48 emotionally valenced target words. After watching the videos, participants completed an auditory word recognition memory task where target words, and the same number of fillers, were presented. The results showed a statistically significant main effect of valence on both reaction times and accuracy. Positive words were recognised more accurately and faster than neutral and negative words, but no difference between neutral and negative stimuli was found. These findings fit in well within the gradient model of automatic vigilance, which implies that emotional valence has a monotonic effect on processing latencies during auditory recognition memory in a foreign language.

Superior verbal but not nonverbal memory in congenital blindness.

Previous studies suggest that people who are congenitally blind outperform sighted people on some memory tasks. Whether blindness-associated memory advantages are specific to verbal materials or are also observed with nonverbal sounds has not been determined. Congenitally blind individuals (n = 20) and age and education matched blindfolded sighted controls (n = 22) performed a series of auditory memory tasks. These included: verbal forward and backward letter spans, a complex letter span with intervening equations, as well as two matched recognition tasks: one with verbal stimuli (i.e., letters) and one with nonverbal complex meaningless sounds. Replicating previously observed findings, blind participants outperformed sighted people on forward and backward letter span tasks. Blind participants also recalled more letters on the complex letter span task despite the interference of intervening equations. Critically, the same blind participants showed larger advantages on the verbal as compared to the nonverbal recognition task. These results suggest that blindness selectively enhances memory for verbal material. Possible explanations for blindness-related verbal memory advantages include blindness-induced memory practice and 'visual' cortex recruitment for verbal processing.

Multitasking costs on metacognition in a triple-task paradigm.

Multitasking situations, such as using one's phone while driving, are increasingly common in everyday life. Experimental psychology has long documented the costs of multitasking on task performance; however, little is known of the effects it has on the metacognitive processes that monitor such performance. The present study is a step toward filling this void by combining psychophysical procedures with complex multitasking. We devised a multimodal paradigm in which participants performed a sensorimotor tracking task, a visual discrimination task, and an auditory 2-back working memory task, either separately or concurrently, while also evaluating their task performance every ~15 s. Our main finding is that multitasking decreased participants' awareness of their performance (metacognitive sensitivity) for all three tasks. Importantly, this result was independent of the multitasking cost on task performance, and could not be attributed to confidence leak, psychological refractory period, or recency effects on self-evaluations. We discuss the implications of this finding for both metacognition and multitasking research.