Cognition in Euthymic Patients with Bipolar Disorder: Do Not Forget to Account for Anxiety!

Purpose: Despite the high prevalence of anxiety disorders in BD and its known impact on cognitive performance, the presence and severity of anxious symptoms is not systematically evaluated in studies on cognition in BD. Our aim was to determine if attention and/or inhibition of cognitive interference in euthymic patients with type I Bipolar Disorder (BD-I) is affected by symptoms of anxiety. Patients and Methods: Eighty-seven euthymic BD-I patients were included. Patients with comorbidities other than Generalized Anxiety Disorder (GAD) or Panic Disorder (PD) were excluded. State anxiety was measured with the Brief Inventory of Anxious Responses and Situations (ISRA-B). Subjective cognitive performance was evaluated with the COBRA scale, attention with the Digit-Span Forward task and inhibition of cognitive interference was assessed with the StroopTest interference score. Multiple linear regression models were used to test if anxious symptoms were associated with attention or inhibition of cognitive interference, considering other known contributors for cognitive impairment. Results: Attention was unaffected by anxiety symptoms, but the overall regression for inhibition of cognitive interference was significant: years of schooling (ß=1.12, p = 0.001), cognitive complaints (ß=0.44, p = 0.008), and anxiety (ß=-0.21, p = 0.017) explained 15% of the interference score of the Stroop test (R2 = 0.15). Conclusion: Beyond residual affective symptoms, anxious symptoms seem to affect inhibition of cognitive interference. We recommend routine testing of anxiety when considering cognitive evaluations, especially when screening for cognitive deficits.

Screen Time Exposure and Domain-Specific Working Memory in Young Adults.

Introduction With technology advancing across all fields, the utility of digital screens is increasing among all age groups for various purposes. Research indicates that while digital technology presents clear advantages, prolonged exposure can have detrimental effects on various aspects of health, behavior, emotions, and cognitive functions like attention and working memory. A crucial cognitive process for learning and information processing which is working memory, can be affected by factors including screen time. Studies have found that the impact of screen time on working memory can be negative, positive, or show no discernible relationship. However, earlier investigations are limited to smartphone use as screen time exposure and further to only active screen time. As there is a dearth of studies in the Indian context and young adults are more exposed to screen time, it is important to investigate along these lines. Hence, the present study aimed to investigate the impact of active and passive screen time exposure on modality-specific working memory in young adults. Methods Seventy-seven neurotypical individuals aged between 18 and 22 years were recruited. The study utilized auditory and visual reverse digit span tasks and the Corsi-backward task to measure working memory span. Screen time data of the participants were collected through a self-administered 18-item questionnaire covering active and background screen time domains. Results and discussion The present study concluded that only active screen time has a significant effect on visual reverse digit span and supports the notion of the visual superiority effect against an auditory superior effect as suggested by earlier findings. The preliminary findings of correlation observed exclusively within the visual domain in this study could be attributed to the potential impact of screen time exposure (active screen time and textual content). Screen usage demands effective switching between various visual stimuli and ongoing updates of information in memory. Nonetheless, interpreting this explanation and generalization requires caution, given the low ecological validity of the task employed in the study. Future investigations should aim to collect screen time exposure data more objectively, perhaps through online tracking techniques. Furthermore, it would be prudent to expand the correlation analysis to include other cognitive processes and populations.

Aging's Effect on Working Memory-Modality Comparison.

Research exploring the impact of development and aging on working memory (WM) has primarily concentrated on visual and verbal domains, with limited attention paid to the tactile modality. The current study sought to evaluate WM encompassing storage and manipulation across these three modalities, spanning from childhood to old age. The study included 134 participants, divided into four age groups: 7-8, 11-12, 25-35, and 60-69. Each participant completed the Visuospatial Span, Digit Span, and Tactual Span, with forward and backward recall. The findings demonstrated a consistent trend in both forward and backward stages. Performance improved until young adulthood, progressively diminishing with advancing age. In the forward stage, the Tactual Span performance was worse than that of the Digit and Visuospatial Span for all participants. In the backward stage, the Visuospatial Span outperformed the Digit and Tactual Span across all age groups. Furthermore, the Tactual Span backward recall exhibited significantly poorer performance than the other modalities, primarily in the youngest and oldest age groups. In conclusion, age impacts WM differently across modalities, with tactile storage capacity being the most vulnerable. Additionally, tactile manipulation skills develop later in childhood but deteriorate sooner in adulthood, indicating a distinct component within tactile WM.

Complex executive functions assessed by the trail making test (TMT) part B improve more than those assessed by the TMT part A or digit span backward task during vagus nerve stimulation in patients with drug-resistant epilepsy.

Introduction: There is a paucity of clinical studies examining the long-term effects of vagus nerve stimulation (VNS) on cognition, although a recent study of patients with drug-resistant epilepsy (DRE) treated with VNS therapy demonstrated significant improvement in executive functions as measured by the EpiTrack composite score. The present study aimed to investigate performance variability in three cognitive tests assessing executive functions and working memory in a cohort of DRE patients receiving VNS therapy during a follow-up duration of up to 5 years. Methods: The study included 46 DRE patients who were assessed with the Trail Making Test (TMT) (Parts A and B) and Digit Span Backward (DB) task prior to VNS implantation, 6 months and 12 months after implantation, and yearly thereafter as a part of the clinical VNS protocol. A linear mixed-effects (LME) model was used to analyze changes in test z scores over time, accounting for variations in follow-up duration when predicting changes over 5 years. Additionally, we conducted descriptive analyses to illustrate individual changes. Results: On average, TMT-A z scores improved by 0.024 units (95% confidence interval (CI): 0.006 to 0.042, p = 0.009), TMT-B z scores by 0.034 units (95% CI: 0.012 to 0.057, p = 0.003), and DB z scores by 0.019 units per month (95% CI: 0.011 to 0.028, p < 0.001). Patients with psychiatric comorbidities achieved the greatest improvements in TMT-B and DB z scores among all groups (0.0058 units/month, p = 0.036 and 0.028 units/month, p = 0.003, respectively). TMT-A z scores improved the most in patients taking 1-2 ASMs as well as in patients with psychiatric comorbidities (0.042 units/month, p = 0.002 and p = 0.003, respectively). Conclusion: Performance in all three tests improved at the group level during the follow-up period, with the most robust improvement observed in TMT-B, which requires inhibition control and set-switching in addition to the visuoperceptual processing speed that is crucial in TMT-A and working-memory performance that is essential in DB. Moreover, the improvement in TMT-B was further enhanced if the patient had psychiatric comorbidities.

Neural mechanisms of sentence production: a volumetric study of primary progressive aphasia.

Studies on the neural bases of sentence production have yielded mixed results, partly due to differences in tasks and participant types. In this study, 101 individuals with primary progressive aphasia (PPA) were evaluated using a test that required spoken production following an auditory prime (Northwestern Assessment of Verbs and Sentences-Sentence Production Priming Test, NAVS-SPPT), and one that required building a sentence by ordering word cards (Northwestern Anagram Test, NAT). Voxel-Based Morphometry revealed that gray matter (GM) volume in left inferior/middle frontal gyri (L IFG/MFG) was associated with sentence production accuracy on both tasks, more so for complex sentences, whereas, GM volume in left posterior temporal regions was exclusively associated with NAVS-SPPT performance and predicted by performance on a Digit Span Forward (DSF) task. Verb retrieval deficits partly mediated the relationship between L IFG/MFG and performance on the NAVS-SPPT. These findings underscore the importance of L IFG/MFG for sentence production and suggest that this relationship is partly accounted for by verb retrieval deficits, but not phonological loop integrity. In contrast, it is possible that the posterior temporal cortex is associated with auditory short-term memory ability, to the extent that DSF performance is a valid measure of this in aphasia.

Americans have a longer digit span but a shorter spatial span than Finns.

OBJECTIVE: Cross-national studies of test norms show American superiority in digit span (DS) length as compared to European norms. In our study, American and Finnish DS and Spatial span (SS) norms were analyzed to study the hypothesis that the differences in DS reflect a systemic difference in working memory and are not based on linguistic factors. METHOD: The mean DS and SS scores from the Wechsler Memory Scale III US (n = 1,250) and Finnish (n = 251) standardizations were compared. RESULTS: A significant difference between American and Finnish mean DS (16.5-14.2) and SS (14.7-15.9) raw scores was observed. For six out of seven age groups, the American sample had longer DS while for 4/7 age groups, the Finnish sample had longer SS. CONCLUSIONS: It is concluded that differences in DS are based on other factors than a systemic difference in working memory. Cross-national differences in articulatory duration of digit names is probably one major causative factor. The results underline the need for establishing national test norms for memory tests.

The effects of creatine supplementation on cognitive performance-a randomised controlled study.

BACKGROUND: Creatine is an organic compound that facilitates the recycling of energy-providing adenosine triphosphate (ATP) in muscle and brain tissue. It is a safe, well-studied supplement for strength training. Previous studies have shown that supplementation increases brain creatine levels, which might increase cognitive performance. The results of studies that have tested cognitive performance differ greatly, possibly due to different populations, supplementation regimens, and cognitive tasks. This is the largest study on the effect of creatine supplementation on cognitive performance to date. METHODS: Our trial was preregistered, cross-over, double-blind, placebo-controlled, and randomised, with daily supplementation of 5 g for 6 weeks each. We tested participants on Raven's Advanced Progressive Matrices (RAPM) and on the Backward Digit Span (BDS). In addition, we included eight exploratory cognitive tests. About half of our 123 participants were vegetarians and half were omnivores. RESULTS: Bayesian evidence supported a small beneficial effect of creatine. The creatine effect bordered significance for BDS (p = 0.064, η2P = 0.029) but not RAPM (p = 0.327, η2P = 0.008). There was no indication that creatine improved the performance of our exploratory cognitive tasks. Side effects were reported significantly more often for creatine than for placebo supplementation (p = 0.002, RR = 4.25). Vegetarians did not benefit more from creatine than omnivores. CONCLUSIONS: Our study, in combination with the literature, implies that creatine might have a small beneficial effect. Larger studies are needed to confirm or rule out this effect. Given the safety and broad availability of creatine, this is well worth investigating; a small effect could have large benefits when scaled over time and over many people. TRIAL REGISTRATION: The trial was prospectively registered (drks.de identifier: DRKS00017250, https://osf.io/xpwkc/ ).

A cognitive marker for Alzheimer disease pathology in primary progressive aphasia? A validation study in the clinical setting.

We validated in the clinical setting a putative clinical marker for a biological diagnosis of primary progressive aphasia (PPA) due to amyloid previously identified in an autopsy cohort and including impaired (score ≤4) digit span (DS) as index of phonological loop dysfunction and broadened criteria for logopenic PPA. In 29 PPA patients with an amyloid-positive (A+) biomarker and 28 PPA patients with an amyloid-negative (A-) biomarker, Receiver Operating Characteristics (ROC) curve analysis showed moderate specificity (71%) but insufficient sensitivity (41%) for the proposed marker. Specificity was particularly poor (58%) for the discrimination between A+ PPA and the A- subgroup with nonfluent PPA. DS may be compromised in both logopenic and nonfluent PPA, whose loci of neurodegeneration lie at the 2 ends of the left fronto-parieto-temporal system that underpins phonology. An Statistical Parametric Mapping (SPM) correlation analysis between DS score and metabolism on brain 18-fluoro-deoxy-glucose positron emission tomography also showed a major contribution of the left frontal cortex to impaired span.

French adult normative data for a Standard Executive Neuropsychological Test Battery.

OBJECTIVE: Executive impairments are frequent and may concern a large spectrum of health conditions throughout life. Given the complexity of the executive functions, their assessment requires the administration of multiple tests. There is only one source of French-language normative data for seven traditional executive tests for adults under age 50. The aim of the present study was to establish demographically adjusted normative data of four executive tests commonly used during the neuropsychological assessment in France for adults aged 18-65. METHOD: The following tools were administered to 518 community adults aged from 18 to 65: Digit Span, Trail Making Test, Color Word Interference Test, and Verbal Fluency Test. An Overall Test Battery Mean was computed. Multiple regressions were computed for normally distributed scores and percentiles were established for non-normally distributed scores. RESULTS: Multiple regression analyses indicated that younger age and higher education were both associated with better performance. Age did not predict the number of correct responses on the Verbal Fluency Test. Gender did not have any effect on executive performances. Regression equations to calculate Z-scores are presented. Percentiles are presented for the number of recorded errors on the Trail Making Test, Color Word Interference Test, and Verbal Fluency Test. CONCLUSIONS: We provide reliable and updated norms for four executive tests that are among the most used by clinical neuropsychologists in France. Our work represents a valuable addition to the limited norms currently available for the assessment of executive functions in French young and middle-aged adults.

Neurocognitive Operations Underlying Working Memory Abilities: An Analysis of Latency and Time-Based Parameters.

BACKGROUND: The theory of executive attention (Fuster, 2015) suggests considerable plasticity regarding when specific neurocognitive operations are recruited to bring executive tasks to fruition. OBJECTIVE: We tested the hypothesis that differing neurocognitive operations are recruited upon the initiation of a response, but that other distinct neurocognitive operations are recruited towards the middle or end of a response. METHODS: The Backward Digit Span Test (BDST) was administered to 58 memory clinic patients (MCI, n = 22; no-MCI, n = 36). Latency to generate all correct 5-span responses was obtained. Statistical analyses found that optimal group classification was achieved using the first and third digit backward. First and third response latencies were analyzed in relation to verbal working memory (WM), visual WM, processing speed, visuospatial operations, naming/lexical access, and verbal episodic memory tests. RESULTS: For the first response, slower latencies were associated with better performance in relation to verbal WM and visuospatial test performance. For the third response, faster latencies were associated with better processing speed and visuospatial test performance. CONCLUSION: Consistent with the theory of executive attention, these data show that the neurocognitive operations underlying successful executive test performance are not monolithic but can be quite nuanced with differing neurocognitive operations associated with specific time epochs. Results support the efficacy of obtaining time-based latency parameters to help disambiguate successful executive neurocognitive operations in memory clinic patients.

A short and simple bedside test to detect cognitive fluctuations in patients with dementia with Lewy bodies.

BACKGROUND AND PURPOSE: The establishment of cognitive fluctuations is important when dementia with Lewy bodies (DLB) is suspected but can be especially difficult in the absence of a caregiver who lives with the patient. We examined the possibility of using fluctuating scores on a forward (FDS) and a backward digit span (BDS) test as a marker for cognitive fluctuation. METHODS: Patients with DLB (21), other forms of dementia (14 with Alzheimer's disease, 8 with vascular dementia) and 20 controls were asked to perform an FDS and BDS twice, with an interval of 20 min. RESULTS: Seventy percent of patients with DLB showed evidence of cognitive fluctuations for at least one test, while less than 10% of controls and patients with other dementias did. Evidence of cognitive fluctuations on at least one of both tests classified 83% of patients correctly (i.e. DLB or not), with a sensitivity of 70% and a specificity of 90%. CONCLUSIONS: Repeated forward and backward digit span tests seem a valid, short, easy and inexpensive bedside tool to detect cognitive fluctuations in the diagnostic work-up of DLB, even in the absence of a caregiver, which limits the use of questionnaires.

The classical backward digit span task detects changes in working memory but is unsuitable for classifying the severity of dementia.

Dementia is characterized by the deterioration of working memory (WM). The backward digit span (DS) task and reading span test (RST) are measures of WM. DS task and RST have not been directly compared in assessing dementia. This study aimed to compare the performance of individuals with dementia in forward and backward DS tasks to that in RST. We investigated the ability of forward/backward DS tasks to discriminate dementia severity. Forward/backward DS tasks and RST were performed in 15 elderly Japanese individuals with dementia. Twenty-six and 20 elderly individuals for the DS task and RST, respectively, were included as controls. Clinical Dementia Rating scale (CDR) was used to evaluate dementia severity. DS task scores were significantly correlated with RST scores. Both types of DS tasks correlated with RST, only the RST distinguished dementia severity based on CDR. Our findings indicate that the backward DS task may detect WM decline in dementia, but the RST is more suitable for assessing dementia severity. The backward DS task may be an effective screening measure for dementia signs in the elderly and may be used to identify patients requiring further assessments such as the RST to evaluate dementia severity based on WM performance.

Optimal per test cutoff scores and combinations of failure on multiple embedded performance validity tests in detecting performance invalidity in a mixed clinical sample.

We tested the usefulness of six embedded performance validity tests (EPVTs) in identifying performance invalidity in a mixed clinical sample. Using a retrospective design, 181 adults were classified as valid (n = 146) or invalid (n = 35) performance based upon their performance on one of three standalone PVTs (Test of Memory Malingering, Victoria Symptom Validity Test, Dot Counting Test). Multiple cutoffs were identified corresponding to predetermined false positive rates of 0, 5, 10, and 15% for each of six EPVTs. EPVT cutoffs corresponding to the predetermined false positive benchmarks were generally more conservative than currently established scores. Sensitivity was low (.0%-42.9%) for individual EPVTs across these cutoffs and was moderately improved by the combination of multiple EPVT failures. The optimal number of EPVT failures using the 10% false positive rate was ≥ 2. Although the overall classification accuracy of 80.7% and specificity of 89.0% were comparable to prior research, the sensitivity of 45.7% was more modest than previous estimates. Low sensitivities indicate that this combination of EPVTs failed to detect a majority of invalid performers.

Sensorimotor and working memory systems jointly support development of perceptual rhythm processing.

We studied the role of sensorimotor and working memory systems in supporting development of perceptual rhythm processing with 119 participants aged 7-12 years. Children were assessed for their abilities in sensorimotor synchronization (SMS; beat tapping), auditory working memory (AWM; digit span), and rhythm discrimination (RD; same/different judgment on a pair of musical rhythm sequences). Multiple regression analysis revealed that children's RD performance was independently predicted by higher beat tapping consistency and greater digit span score, with all other demographic variables (age, sex, socioeconomic status, music training) controlled. The association between RD and SMS was more robust in the slower tempos (60 and 100 beats-per-minute (BPM)) than faster ones (120 and 180 BPM). Critically, the relation of SMS to RD was moderated by age in that RD performance was predicted by beat tapping consistency in younger children (age: 7-9 years), but not in older children (age: 10-12 years). AWM was the only predictor of RD in older children. Together, the current findings demonstrate that the sensorimotor and working memory systems jointly support RD processing during middle-to-late childhood and that the degree of association between the two systems and perceptual rhythm processing is shifted before entering into early adolescence.

Moderators of metacognitive strategy training for executive functioning in early schizophrenia and psychosis risk.

Goal Management Training (GMT) improved self-reported executive functioning in a recent randomized, controlled trial in early intervention for psychosis participants. Little is known about the mechanism for this benefit, so this study investigates objectively measured executive function, the difference between subjective and objective executive function, independent living and employment status as potential moderators of efficacy of GMT. Baseline scores from 81 participants (GMT n = 39 vs Treatment-as-usual; TAU n = 42) were analyzed in a linear mixed model analysis for repeated measures as predictors of improvement on the self-reported Behavior Rating Inventory of Executive Function-Adult version (BRIEF-A) immediately and 30 weeks after GMT. Potential moderators were scores from objective measures of executive functioning, discrepancy between subjective and objective measures, independent living and employment status. Discrepancy was assessed by comparing four clusters of participants with differing patterns of scores. The effect of GMT remained significant regardless of initial objective executive functioning at baseline. Those with higher subjective complaints at baseline in two clusters with (i) both objective and subjective executive dysfunction, and (ii) mostly subjective executive dysfunction experienced greater change after treatment. Living arrangements or participation in education or work did not significantly moderate the effects of GMT. Poor performance on neuropsychological tasks is not an obstacle to making use of GMT, but further knowledge is needed about the benefits of strategy training for individuals with a combination of poor performance with few subjective complaints.

A Direct Comparison of 10 WAIS-IV Digit Span Embedded Validity Indicators among a Mixed Neuropsychiatric Sample with Varying Degrees of Cognitive Impairment.

OBJECTIVE: Reliable Digit Span (RDS), RDS-Revised (RDS-R), and age-corrected scaled score (ACSS) have been previously validated as embedded performance validity tests (PVTs) from the Wechsler Adult Intelligence Scale-IV Digit Span subtest (WAIS-IV DS). However, few studies have directly compared the relative utility of these and other proposed WAIS-IV DS validity indicators within a single sample. METHOD: This study compared classification accuracies of 10 WAIS-IV DS indices in a mixed neuropsychiatric sample of 227 outpatients who completed a standardized neuropsychological battery. Participants with ≤1 PVT failures of the four, freestanding criterion PVTs constituted the valid group (n = 181), whereas those with ≥2 PVT failures formed the invalid group (n = 46). Among the valid group, 113 met criteria for mild cognitive impairment (MCI). RESULTS: Classification accuracies for all DS indicators were statistically significant across the overall sample and subsamples with and without MCI, apart from indices derived from the Forward trial in the MCI sample. DS Sequencing ACSS, working memory RDS (wmRDS), and DS ACSS emerged as the most effective predictors of validity status, with acceptable to excellent classification accuracy for the overall sample (AUCs = 0.792-0.816; 35%-50% sensitivity/88%-96% specificity). CONCLUSIONS: Although most DS indices demonstrated clinical utility as embedded PVTs, DS Sequencing ACSS, wmRDS, and DS ACSS may be particularly robust to cognitive impairment, minimizing risk of false positive errors while identifying noncredible performance. Moreover, DS indices incorporating data from multiple trials (i.e., wmRDS, DS ACSS) also generally yielded greater classification accuracy than those derived from a single trial.

Teleneuropsychology: normative data for the assessment of memory in online settings.

INTRODUCTION: The COVID-19 pandemic has forced significant changes in clinical practice. Psychologists and neuropsychologists had to modify their settings to assess patients' abilities, switching from an in-person modality to a remote setting by using video calling platforms. Consequently, this change brought about the need for new normative data tailored to remote settings. AIM AND METHODS: The study aimed to develop normative data for the online assessment of neuropsychological memory tests and to compare it with the published norms obtained in standard settings. Two hundred and four healthy Italian volunteers performed three verbal memory tests through the Google Meet platform: the Digit Span (Backward and Forward), the Rey Auditory Verbal Learning, and the Verbal Paired Associated Learning Test. RESULTS: This research provides specific norms that consider the influence of demographic characteristics. Their comparison with published norms shows a medium to high agreement between systems. The present study provides a reference for the clinical use of neuropsychological instruments to assess verbal memory in a remote setting and offers specific recommendations.

Iron deficiency and cognitive impairment in children with low blood lead levels.

Background: The relationship between iron deficiency (ID) and children's neurocognitive functions has attracted the interest of the scientific community, particularly among those living at the lead-contaminated sites. Thus, the current paper aims at evaluating the association between ID and neurocognitive performance of school children living in a mining area (CMA) in comparison with a control group (CG). Methods: he study involves 90 school children aged from 6 to 10 years old. A survey was conducted to obtain information on the socio-economic and demographic status of the children. The students underwent cognitive test battery including the Bell Dam Test (BDT) and the Digit Span test (DST). Iron status (IS) was determined by serum iron, ferritin, transferrin, and blood count (CBC). Blood lead levels (BLLs) were measured by the Graphite Furnace Atomic Absorption Spectrophotometer (SAA-FG). Results: An ID was observed in 23.3 % of CMA, but it is not statistically different from the CG 21.7 % (p = 0.774). CMA group exhibited elevated BLLs (3.5 ± 1.21 µg/dL) when compared to the CG (2.31 ± 0.95 µg/dL), p = 0.006. Children's performance on the visual attention test (VA) was impaired in both groups. Working memory (WM) abilities were normal. In bivariate analysis, no difference was demonstrated in mean BLLs between the students who adopt the disorganized scanning strategy compared to the others whose method is organized for both CMA (t = - 0.508, p = 0.616) and CG (t = - 0.014, p = 0.989). Multivariate models did not reveal any association between IS and cognitive scores of children in the two groups (p > 005). Nevertheless, daily milk consumption was positively associated to VA skills among CMA. A negative influence of BLLs above the threshold value of 5 µg/dL was determined on children's WM skills. Conclusion: Our results suggest that low-level lead exposure did not influence children's visual attention scores but may adversely affect WM abilities if it reaches the threshold value of 5 µg/dL regardless of their IS.

Immediate Effects of (Simulated) Age-Related Hearing Loss on Cognitive Processing and Performance for the Backward-Digit-Span Task.

The recall of auditorily presented sequences of digits in reverse order (also known as the Backward Digit Span, BDS) is considered to reflect a person's information storage and processing abilities which have been linked to speech-in-noise intelligibility. However, especially in aging research and audiology, persons who are administered the BDS task are often affected by hearing loss (HL). If uncorrected, HL can have immediate assessment-format-related effects on cognitive-test performance and can result, in the long term, in neuroplastic changes impacting cognitive functioning. In the present study, an impairment-simulation approach, mimicking mild-to-moderate age-related HLs typical for persons aged 65, 75, and 85 years, was used in 19 young normal-hearing participants to evaluate the impact of HL on cognitive performance and the cognitive processes probed by the BDS task. Participants completed the BDS task in several listening conditions, as well as several commonly used visual tests of short-term and working memory. The results indicated that BDS performance was impaired by a simulated HL representing that of persons aged 75 years and above. In the normal-hearing condition, BDS performance correlated positively with both performance on tests of short-term memory and performance on tests of working memory. In the listening condition simulating moderate HL (as experienced by the average 85-year-old person), BDS performance only correlated with performance on working-memory tests. In conclusion, simulated (and, by extrapolation, actual) age-related HL negatively affects cognitive-test performance and may change the composition of the cognitive processes associated with the completion of a cognitive task.

A low- dose of caffeine suppresses EEG alpha power and improves working memory in healthy University males.

The effects of a low dose of caffeine, administered in the morning, on brain wave activity and cognitive function were investigated in 25 healthy university Southeast Asian men (mean age ±standard deviation: 21 ± 2 years). Participants received a placebo (PLA) or a 50 mg caffeinated drink (CAF) under randomized, double-blind crossover conditions, with 1 week between conditions. Brain wave activity was assessed using electroencephalography (EEG) from a 5 min eyes-closed resting state. Cognitive function, i.e., visuomotor processing speed, working memory, and attention were assessed using the trail-making test A (Trails A) and B (Trails B), and digit span Forwards (DF), respectively. All tests were examined before drinking (BD), 30 min after drinking (AD), and 35 min after 5-min isokinetic exercise (AE). [Results] The CAF showed a significant decrease in the percentage changes from baseline (%∆) of alpha wave activity over the midline electrodes, i.e., frontal, central, and occipital areas after AD (p<0.05). Data from cognitive function tests were significantly improved after AD (p<0.05). A significant inverse correlation between the diminished alpha wave activity over the midline central and occipital cortical regions and the Trails B positive scores were observed (p<0.05). [Conclusion] The diminishment in resting alpha wave activity and improvement of cognitive function on working memory assessed by the Trails B following caffeine consumption would support the stimulant effects of low-dose caffeine as a morning wake-up drink in young adults.