Auditory Processing but Not Peripheral Hearing Differs Between Older Adults With and Without Mild Cognitive Impairment.

PURPOSE: Impairments of hearing and auditory processing (AP) have been indicated as risk factors for dementia, but it remains unclear if persons with clinically diagnosed mild cognitive impairment (MCI) show such impairments. The objective of these analyses was to compare AP between those with and without a clinical diagnosis of MCI using a battery of AP measures. METHOD: Data from 274 older adults from the Keys to Staying Sharp randomized clinical trial (NCT03528486) were analyzed. A battery of AP measures in which three domains (temporal processing, binaural processing, and degraded speech understanding) were addressed by six tests was administered. Analyses were registered at https://osf.io/nga4v. RESULTS: Those with and without a clinical diagnosis of MCI differed significantly in age, p = .002; pure-tone hearing in the left ear, p = .007; sex, p = .015; and race, p < .001. These covariates were included in multivariate analysis of covariance, which indicated significant differences between persons with and without MCI on measures of binaural processing (ps ≤ .006), but not on measures of temporal processing or degraded speech (ps ≥ .093). Pure-tone hearing averages did not significantly differ among those with or without MCI after adjusting for age, sex, and race (ps ≥ .292). CONCLUSIONS: AP in the binaural domain is impaired in MCI, but peripheral hearing did not significantly differ between those with and without MCI. Poor performance on AP measures of binaural processing may reflect problems dividing attention and may be indicative of dementia risk. Results have clinical implications for early detection of and intervention for cognitive impairment.

The Preventing Alzheimer's with Cognitive Training (PACT) randomized clinical trial.

BACKGROUND: To address the rising prevalence of Alzheimer's disease and related dementias, effective interventions that can be widely disseminated are warranted. The Preventing Alzheimer's with Cognitive Training study (PACT) investigates a commercially available computerized cognitive training program targeting improved Useful Field of View Training (UFOVT) performance. The primary goal is to test the effectiveness of UFOVT to reduce incidence of clinically defined mild cognitive impairment (MCI) or dementia with a secondary objective to examine if effects are moderated by plasma ß-amyloid level or apolipoprotein E e4 (APOE e4) allele status. METHODS/DESIGN: This multisite study utilizes a randomized, controlled experimental design with blinded assessors and investigators. Individuals who are 65 years of age and older are recruited from the community. Eligible participants who demonstrate intact cognitive status (Montreal Cognitive Assessment score > 25) are randomized and asked to complete 45 sessions of either a commercially available computerized-cognitive training program (UFOVT) or computerized games across 2.5 years. After three years, participants are screened for cognitive decline. For those demonstrating decline or who are part of a random subsample, a comprehensive neuropsychological assessment is completed. Those who perform below a pre-specified level are asked to complete a clinical evaluation, including an MRI, to ascertain clinical diagnosis of normal cognition, MCI, or dementia. Participants are asked to provide blood samples for analyses of Alzheimer's disease related biomarkers. DISCUSSION: The PACT study addresses the rapidly increasing prevalence of dementia. Computerized cognitive training may provide a non-pharmaceutical option for reducing incidence of MCI or dementia to improve public health. REGISTRATION: The PACT study is registered at http://Clinicaltrials.govNCT03848312.

Applying the Health Belief Model to Quantify and Investigate Expectations for Computerized Cognitive Training.

Despite the demonstrated benefits of computerized cognitive training for older adults, little is known about the determinants of training behavior. We developed and tested scales to quantify expectations about such training, examine whether expectations predicted training adherence, and explore if training expectations changed from pre- to post-training. Participants (N=219) were healthy older adults aged 55-96 years (M=75.36, SD=9.39), enrolled in four studies investigating Dakim, Insight, or Posit Science Brain Fitness computerized cognitive training programs. Instruments were adapted from existing health behavior scales: Self Efficacy for Cognitive Training, Outcome Expectations for Cognitive Training, Perceived Susceptibility to Cognitive Decline, Dementia or Alzheimer's Disease, and Perceived Severity of Cognitive Decline, Dementia or Alzheimer's Disease. Participants completed scales at baseline (N=219) and post-training (n=173). Eight composites were derived from factor analyses. Adherence rates were high (M=81%), but none of the composites predicted training adherence. There was an overall significant effect of time, Wilks' λ=.843, F(8, 114)=2.65, p=.010, partial η 2 =.157, a significant overall effect of training group, Wilks' λ=.770, F(16, 228)=1.99, p=.015, partial η 2 =.123, and an overall significant group x time interaction, Wilks' λ=.728, F(16, 226)=2.44, p=.002, partial η 2 =.147. Significant effects of time were found for expected psychological outcomes and self-efficacy. Post-training, participants more strongly agreed that training was enjoyable and increased their sense of accomplishment. Changes in self-efficacy for cognitive training varied by program, improvingfor Dakim- and declining for the more challenging Brain Fitness- and InSight participants. These newly devised scales may be useful for examining cognitive training behaviors. However, more work is needed to understand factors that influence older adults' enrollment in and adherence to cognitive training.

Are auditory processing and cognitive performance assessments overlapping or distinct? Parsing the auditory behaviour of older adults.

OBJECTIVE: Auditory processing predicts cognitive decline, including dementia, in older adults. Auditory processing involves the understanding, interpretation, and communication of auditory information. Cognition is linked to auditory processing; however, it is disputed whether auditory processing is a separate construct distinct from cognition. The purpose of this study was to determine if auditory processing is distinct from cognition in older adults. DESIGN: Participants completed 14 cognitive and auditory processing assessments. Assessments were subjected to exploratory factor analysis with principal components extraction and varimax rotation with Kaiser normalisation. Study sample: 213 community-dwelling older adults (M = 71.39 years, 57% female, 93% Caucasian, M = 16 years education) with and without mild cognitive impairment (MCI) participated. RESULTS: Four factors were identified, explaining 66.3% of the total variance: (1) executive functions, visual processing speed, and dichotic auditory processing, (2) auditory processing of degraded speech, (3) memory, and (4) auditory temporal processing of nonspeech. CONCLUSIONS: Two domains of auditory processing (processing degraded speech and temporal processing) account for unique variance to which cognitive measures are not sensitive, while measures of auditory dichotic processing appear to be tapping similar abilities as measures of cognition. Older adults who perform poorly on dichotic measures should be screened for cognitive impairment.

Cortical auditory evoked potentials in mild cognitive impairment: Evidence from a temporal-spatial principal component analysis.

Mild cognitive impairment (MCI) is considered an intermediate transitional stage for the development of dementia, especially Alzheimer's disease. The identification of neurophysiological biomarkers for MCI will allow improvement in detecting and tracking the progression of cognitive impairment. The primary objective of this study was to compare cortical auditory evoked potentials between older adults with and without probable MCI to identify potential neurophysiological indicators of cognitive impairment. We applied a temporal-spatial principal component analysis to the evoked potentials achieved during the processing of pure tones and speech sounds, to facilitate the separation of the components of the P1-N1-P2 complex. The probable MCI group showed a significant amplitude increase in a factor modeling N1b for speech sounds (Cohen's d = .84) and a decrease in a factor around the P2 time interval, especially for pure tones (Cohen's d = 1.17). Moreover, both factors showed a fair discrimination value between groups (area under the curve [AUC] = .698 for N1b in speech condition; AUC = .746 for P2 in tone condition), with high sensitivity to detect MCI cases (86% and 91%, respectively). The results for N1b suggest that MCI participants may suffer from a deficit to inhibit irrelevant speech information, and the decrease of P2 amplitude could be a signal of cholinergic hypoactivation. Therefore, both components could be proposed as early biomarkers of cognitive impairment.

Preliminary evidence of biased attentional mechanisms and reward processing in adults with obsessive-compulsive disorder.

Individuals with obsessive-compulsive-disorder (OCD) may have difficulties in using feedback from rewarding and punishing experiences to optimally guide future decisions. The current aim was to examine how adults with OCD use associative learning feedback to direct attention toward learned stimuli when the action-outcome contingency for those stimuli has changed. Participants first learned to select high-probability (over low-probability) rewarding stimuli and low-probability (over high-probability) loss stimuli. Participants then saw these stimuli as the second of two targets in a task where available attentional resources were limited. Recognition of learned stimuli during limited attention was driven by previously learned stimulus-response associations instead of an attentional benefit toward the most favorable action-outcome associations (reward-associated stimuli), as demonstrated in prior research with non-OCD adults. The current evidence supports the hypothesis that individuals with OCD have difficulties shifting from learned stimulus-response associations when the response-outcome contingencies change.

Factors Affecting HIV Testing among Youth in Kenya.

With the high prevalence of HIV among youth in sub-Saharan Africa, it is vital to better understand factors affecting HIV testing among this population; this is the first step in the HIV treatment cascade. The purpose of this study was to examine factors related to behavioral intentions regarding HIV testing using existing pre-test data from the HIV SEERs (Stigma-reduction via Education, Empowerment, and Research) Project, a community-based participatory research program targeting 13-24-year-olds in Kenya. It was hypothesized that HIV knowledge, social support, subjective well-being, and mental health (depression, anxiety, and stress) would serve as facilitators to HIV testing while projected stigma and substance use would serve as barriers to HIV testing. In partial support of our hypotheses, findings from logistic regression analyses revealed that HIV knowledge, substance use, depression, and social support were significant predictors of HIV testing intentions. However, HIV knowledge and substance use served as facilitators while depression and social support served as barriers. While projected stigma was correlated with HIV testing intentions, it was not a significant predictor in the regression analysis. Subjective well-being, anxiety, and stress were not significant predictors in the regression analysis. These findings have important implications for HIV testing initiatives designed for youth in Kenya as well as future research on HIV testing with this population.

Cognitive Training Enhances Auditory Attention Efficiency in Older Adults.

Auditory cognitive training (ACT) improves attention in older adults; however, the underlying neurophysiological mechanisms are still unknown. The present study examined the effects of ACT on the P3b event-related potential reflecting attention allocation (amplitude) and speed of processing (latency) during stimulus categorization and the P1-N1-P2 complex reflecting perceptual processing (amplitude and latency). Participants completed an auditory oddball task before and after 10 weeks of ACT (n = 9) or a no contact control period (n = 15). Parietal P3b amplitudes to oddball stimuli decreased at post-test in the trained group as compared to those in the control group, and frontal P3b amplitudes show a similar trend, potentially reflecting more efficient attentional allocation after ACT. No advantages for the ACT group were evident for auditory perceptual processing or speed of processing in this small sample. Our results provide preliminary evidence that ACT may enhance the efficiency of attention allocation, which may account for the positive impact of ACT on the everyday functioning of older adults.

Interaction of Musicianship and Aging: A Comparison of Cortical Auditory Evoked Potentials.

OBJECTIVE: The goal of this study was to begin to explore whether the beneficial auditory neural effects of early music training persist throughout life and influence age-related changes in neurophysiological processing of sound. DESIGN: Cortical auditory evoked potentials (CAEPs) elicited by harmonic tone complexes were examined, including P1-N1-P2, mismatch negativity (MMN), and P3a. STUDY SAMPLE: Data from older adult musicians (n = 8) and nonmusicians (n = 8) (ages 55-70 years) were compared to previous data from young adult musicians (n = 40) and nonmusicians (n = 20) (ages 18-33 years). RESULTS: P1-N1-P2 amplitudes and latencies did not differ between older adult musicians and nonmusicians; however, MMN and P3a latencies for harmonic tone deviances were earlier for older musicians than older nonmusicians. Comparisons of P1-N1-P2, MMN, and P3a components between older and young adult musicians and nonmusicians suggest that P1 and P2 latencies are significantly affected by age, but not musicianship, while MMN and P3a appear to be more sensitive to effects of musicianship than aging. CONCLUSIONS: Findings support beneficial influences of musicianship on central auditory function and suggest a positive interaction between aging and musicianship on the auditory neural system.

Perceptual and cognitive neural correlates of the useful field of view test in older adults.

The Useful Field of View Test (UFOV) is often used as a behavioral assessment of age-related decline in visual perception and cognition. Poor performance may reflect slowed processing speed, difficulty dividing attention, and difficulty ignoring irrelevant information. However, the underlying neural correlates of UFOV performance have not been identified. The relationship between older adults' UFOV performance and event-related potential (ERP) components reflecting visual processing was examined. P1 amplitude increased with better UFOV performance involving object identification (subtest 1), suggesting that this task is associated with stimulus processing at an early perceptual level. Better performance in all UFOV subtests was associated with faster speed of processing, as reflected by decreases in P3b latency. Current evidence supports the hypothesis that the UFOV recruits both early perceptual and later cognitive processing involved in attentional control. The implications of these results are discussed.

Cognitive training and selective attention in the aging brain: an electrophysiological study.

OBJECTIVE: Age-related deficits in selective attention are hypothesized to result from decrements in inhibition of task-irrelevant information. Speed of processing (SOP) training is an adaptive cognitive intervention designed to enhance processing speed for attention tasks. The effectiveness of SOP training to improve cognitive and everyday functional performance is well documented. However, underlying mechanisms of these training benefits are unknown. METHODS: Participants completed a visual search task evaluated using event-related potentials (ERPs) before and after 10 weeks of SOP training or no contact. N2pc and P3b components were evaluated to determine SOP training effects on attentional resource allocation and capacity. RESULTS: Selective attention to a target was enhanced after SOP training compared to no training. N2pc and P3b amplitudes increased after training, reflecting attentional allocation and capacity enhancement, consistent with previous studies demonstrating behavioral improvements in selective attention following SOP training. CONCLUSIONS: Changes in ERPs related to attention allocation and capacity following SOP training support the idea that training leads to cognitive enhancement. Specifically, we provide electrophysiological evidence that SOP training may be successful in counteracting age-related declines in selective attention. SIGNIFICANCE: This study provides important evidence of the underlying mechanisms by which SOP training improves cognitive function in older adults.

An examination of mediators of the transfer of cognitive speed of processing training to everyday functional performance.

The purpose of these analyses was to examine mediators of the transfer of cognitive speed of processing training to improved everyday functional performance (J. D. Edwards, V. G. Wadley,, D. E. Vance, D. L. Roenker, & K. K. Ball, 2005, The impact of speed of processing training on cognitive and everyday performance. Aging & Mental Health, 9, 262-271). Cognitive speed of processing and visual attention (as measured by the Useful Field of View Test; UFOV) were examined as mediators of training transfer. Secondary data analyses were conducted from the Staying Keen in Later Life (SKILL) study, a randomized cohort study including 126 community dwelling adults 63 to 87 years of age. In the SKILL study, participants were randomized to an active control group or cognitive speed of processing training (SOPT), a nonverbal, computerized intervention involving perceptual practice of visual tasks. Prior analyses found significant effects of training as measured by the UFOV and Timed Instrumental Activities of Daily Living (TIADL) Tests. Results from the present analyses indicate that speed of processing for a divided attention task significantly mediated the effect of SOPT on everyday performance (e.g., TIADL) in a multiple mediation model accounting for 91% of the variance. These findings suggest that everyday functional improvements found from SOPT are directly attributable to improved UFOV performance, speed of processing for divided attention in particular. Targeting divided attention in cognitive interventions may be important to positively affect everyday functioning among older adults.

Learned predictiveness speeds visual processing.

When humans learn that the presence of a cue predicts the likelihood of an outcome, they can exploit this learned predictiveness, such that formation of subsequent associations between that cue and new outcomes is facilitated. Could such enhanced selection for association arise early enough to facilitate low-level visual processing? In a test of this possibility, adult volunteers first engaged in a value-learning task involving faces that were differentially predictive of monetary wins or losses. Later, in a simple recognition task, these faces were briefly presented for a variable duration and then masked. The critical presentation duration needed to produce criterion-level recognition was measured to index the visual processing speed for each learned face. Critical duration was significantly shorter for stimuli with high learned predictiveness than for stimuli with low learned predictiveness, regardless of whether they were associated with wins or losses. These results show that neural mechanisms involved in predicting future outcomes are able to modulate visual processing efficiency, probably via cortical feedback processes.

Value associations of irrelevant stimuli modify rapid visual orienting.

In familiar environments, goal-directed visual behavior is often performed in the presence of objects with strong, but task-irrelevant, reward or punishment associations that are acquired through prior, unrelated experience. In a two-phase experiment, we asked whether such stimuli could affect speeded visual orienting in a classic visual orienting paradigm. First, participants learned to associate faces with monetary gains, losses, or no outcomes. These faces then served as brief, peripheral, uninformative cues in an explicitly unrewarded, unpunished, speeded, target localization task. Cues preceded targets by either 100 or 1,500 msec and appeared at either the same or a different location. Regardless of interval, reward-associated cues slowed responding at cued locations, as compared with equally familiar punishment-associated or no-value cues, and had no effect when targets were presented at uncued locations. This localized effect of reward-associated cues is consistent with adaptive models of inhibition of return and suggests rapid, low-level effects of motivation on visual processing.

Selective visual attention and motivation: the consequences of value learning in an attentional blink task.

Learning to associate the probability and value of behavioral outcomes with specific stimuli (value learning) is essential for rational decision making. However, in demanding cognitive conditions, access to learned values might be constrained by limited attentional capacity. We measured recognition of briefly presented faces seen previously in a value-learning task involving monetary wins and losses; the recognition task was performed both with and without constraints on available attention. Regardless of available attention, recognition was substantially enhanced for motivationally salient stimuli (i.e., stimuli highly predictive of outcomes), compared with equally familiar stimuli that had weak or no motivational salience, and this effect was found regardless of valence (win or loss). However, when attention was constrained (because stimuli were presented during an attentional blink, AB), valence determined recognition; win-associated faces showed no AB, but all other faces showed large ABs. Motivational salience acts independently of attention to modulate simple perceptual decisions, but when attention is limited, visual processing is biased in favor of reward-associated stimuli.

Centrifugal versus roller head pumps for cardiopulmonary bypass: effect on early neuropsychologic outcomes after coronary artery surgery.

OBJECTIVE: To test the hypothesis that routine use of a centrifugal pump in the cardiopulmonary bypass circuit would result in a lower incidence of early neuropsychologic deficit when compared with conventional roller pumps. DESIGN: Prospective, randomized, double-blind. SETTING: University teaching hospital. PARTICIPANTS: Patients (n = 103) scheduled for elective coronary artery surgery. INTERVENTIONS: Patients were randomized into group C (centrifugal pump for cardiopulmonary bypass; n = 54) and group R (roller pump for cardiopulmonary bypass; n = 49). MEASUREMENTS AND MAIN RESULTS: A neuropsychologic test battery of 6 standard tests was administered before surgery and 5 days after surgery. An abnormal test result was defined as deterioration by >1 group SD from an individual's preoperative test performance. There were no significant differences between groups in preoperative or surgical parameters, intensive care unit stay, or hospital stay. There were no significant differences in the incidence of neuropsychologic deficit for patients with a deficit in at least 1 test (group C, 33%; group R, 51%; odds ratio, 0.48; 95% confidence interval, 0.22 to 1.06) or patients with a deficit in >/=2 tests (group C, 6%; group R, 18%; odds ratio, 0.26; 95% confidence interval, 0.07 to 1.03). In group R, there were more individual test deficits per patient than in group C (p = 0.04). CONCLUSION: There was no significant difference in the incidence of neuropsychologic deficit postoperatively with routine use of centrifugal pumps. The larger number of individual test deficits in the roller pump group suggest that further studies to assess the potential neuropsychologic benefits of the use of centrifugal pumps are warranted.

Management of anxiety after acute myocardial infarction.

BACKGROUND: Anxiety is common after acute myocardial infarction (AMI) and may induce complications and poorer outcome because of activation of the sympathetic nervous system and the hypothalamic pituitary adrenal axis. Little is known about critical care nurses' management of anxiety in the initial days after AMI. OBJECTIVE: The purpose of this study was to describe pharmacological and nonpharmacological anxiety management practices in a sample of patients with AMI and to determine the association between patient self-reported anxiety level, clinician anxiety assessment, and subsequent anxiety management by clinicians. METHODS: In this descriptive, correlational investigation, subjects (n = 101) were requested to complete the Spielberger State Anxiety Inventory (SAI) within 48 hours of hospital admission for AMI. After hospital discharge, the investigators performed a thorough medical records review to evaluate the use of pharmacological and nonpharmacological anxiety management strategies for the period that encompassed 12 hours before and 12 hours after administration of the SAI. RESULTS: Subjects were primarily white (93%), married (72%) individuals with a hospital admission Killip classification of I (71%). Documentation of subjective anxiety assessment was found for only 45 subjects (44.6%). Subject rating of anxiety with SAI ranged from 20 (no anxiety) to 77 (extreme anxiety; mean, 37.2 +/- 12.4). Seventy-two subjects had documentation of anxiety management (pharmacological, 25.7%; nonpharmacological, 45.6%). No significant relationship was seen between the subject SAI score and the clinician assessment of anxiety (lambda = 0.03; P < .05). Although documentation was seen that 72 subjects received anxiety management, no association was found between the clinician evaluation of anxiety and the use of anxiety management strategies (pharmacological: lambda = 0.11; P = .65; nonpharmacological: lambda = 0.07; P = .08). A small but significant relationship was found between the subject SAI score and the use of pharmacological anxiety management (lambda = 0.10; P = .03) but no association was found between SAI score and the use of nonpharmacological anxiety management (lambda = 0.6; P = .50). Evaluation of efficacy was not routinely documented (pharmacological, 58%; nonpharmacological, 2%). Only 2 subjects (2%) received consultation to social work for management of anxiety. CONCLUSION: Anxiety was not systematically and accurately assessed or logically managed in this sample of patients with AMI. Critical care clinicians need a comprehensive understanding about the importance of anxiety to patient outcome in addition to objective, reliable, and valid anxiety measures and a useful repertoire of evidence-based management strategies to effectively manage anxiety. Effective management of anxiety positively influences patient outcome and should be a goal for all critical care patients.