Cognitive Event-Related Potential Responses Differentiate Older Adults with and without Probable Mild Cognitive Impairment.

Background: Older adults rarely seek cognitive assessment, but often visit other healthcare professionals (e.g., audiologists). Noninvasive clinical measures within the scopes of practice of those professions sensitive to cognitive impairment are needed. Purpose: This study examined the differences of probable mild cognitive impairment (MCI) on latency and mean amplitude of the P3b auditory event-related potential. Method: Fifty-four participants comprised two groups according to cognitive status (cognitively normal older adults [CNOA], n = 25; probable MCI, n = 29). P3b was recorded using an oddball paradigm for speech (/ba/, /da/) and non-speech (1000, 2000 Hz) stimuli. Amplitudes and latencies were compared from six electrodes (FPz, Fz, FCz, Cz, CPz, Pz) between groups across stimulus probability and type. Results: CNOA participants had larger P3b mean amplitudes for deviant stimuli than those with probable MCI. Group effects of latency were isolated to deviant stimuli at FCz only when those with unclear P3bs were included. Findings did not covary with age or education. Overall, CNOAs showed a large P3b oddball effect while those with probable MCI did not. Conclusions: P3b can be used to show electrophysiological differences between older adults with and without probable MCI. These results support the development of educational materials targeting professionals using auditory-evoked potentials.

The Role of Personality in a Regular Cognitive Monitoring Program.

OBJECTIVES: This study examines the role of personality in cognitive performance, adherence, and satisfaction with regular cognitive self-monitoring. MATERIALS AND METHODS: One hundred fifty-seven cognitively healthy older adults, age 55+, completed the 44-item Big-Five Inventory and were subsequently engaged in online monthly cognitive monitoring using the Cogstate Brief Battery for up to 35 months (M=14 mo, SD=7 mo). The test measures speed and accuracy in reaction time, visual learning, and working memory tasks. RESULTS: Neuroticism, although not related to cognitive performance overall (P>0.05), was related to a greater increase in accuracy (estimate=0.07, P=0.04) and speed (estimate=-0.09, P=0.03) on One Card Learning. Greater conscientiousness was related to faster overall speed on Detection (estimate=-1.62, P=0.02) and a significant rate of improvement in speed on One Card Learning (estimate=-0.10, P<0.03). No differences in satisfaction or adherence to monthly monitoring as a function of neuroticism or conscientiousness were observed. CONCLUSIONS: Participants volunteering for regular cognitive monitoring may be quite uniform in terms of personality traits, with personality traits playing a relatively minor role in adherence and satisfaction. The more neurotic may exhibit better accuracy and improve in speed with time, whereas the more conscientious may perform faster overall and improve in speed on some tasks, but the effects appear small.

Auditory Processing of Older Adults With Probable Mild Cognitive Impairment.

Purpose: Studies suggest that deficits in auditory processing predict cognitive decline and dementia, but those studies included limited measures of auditory processing. The purpose of this study was to compare older adults with and without probable mild cognitive impairment (MCI) across two domains of auditory processing (auditory performance in competing acoustic signals and temporal aspects of audition). Method: The Montreal Cognitive Assessment (Nasreddine et al., 2005) was used to classify participants as with or without probable MCI. In this cross-sectional study, participants (n = 79) completed 4 measures of auditory processing: Synthetic Sentence Identification with Ipsilateral Competing Message (Gates, Beiser, Rees, D'Agostino, & Wolf, 2002), Dichotic Sentence Identification (Fifer, Jerger, Berlin, Tobey, & Campbell, 1983), Adaptive Tests of Temporal Resolution (ATTR; Lister & Roberts, 2006; across-channel and within-channel subtests), and time-compressed speech (Wilson, 1993; Wilson, Preece, Salamon, Sperry, & Bornstein, 1994). Audiometry was also conducted. Results: Those with probable MCI had significantly poorer performance than those without MCI on Synthetic Sentence Identification with Ipsilateral Competing Message, Dichotic Sentence Identification, and the ATTR within-channel subtest. No group differences were found for time-compressed speech, ATTR across-channel, or audiometric measures. Conclusions: Older adults with cognitive impairment not only have difficulty with competing acoustic signals but may also show poor temporal processing. The profile of auditory processing deficits among older adults with cognitive impairment may include multiple domains.

Regular cognitive self-monitoring in community-dwelling older adults using an internet-based tool.

INTRODUCTION: Monitoring for various health conditions (e.g., breast cancer, hypertension) has become common practice. However, there is still no established tool for regular monitoring of cognition. In this pilot longitudinal study, we examined the utility and feasibility of internet-based cognitive self-monitoring using data from the first 12 months of this ongoing study. METHOD: Cognitively healthy community-dwelling older adults (Montreal Cognitive Assessment ≥ 26) were enrolled on a rolling basis and were trained in self-administration of the internet-based version of the CogState Brief Battery. The battery uses playing cards and includes Detection, Identification, One Back, and One Card Learning subtasks. RESULTS: Of the 118 participants enrolled, 26 dropped out, mostly around first in-home session. Common reasons for participant attrition were internet browser problems, health problems, and computer problems. Common reasons for delayed session completion were being busy, being out of town, and health problems. Participants needed about one reminder phone call per four completed sessions or one reminder email per five completed sessions. Performance across the monthly sessions showed slight (but significant) improvement on three of the four tasks. Change in performance was unaffected by individual characteristics with the exception of previous computer use, with less frequent users showing greater improvement on One Card Learning. We also found low intraindividual variability in monthly test scores beyond the first self-administered testing session. CONCLUSIONS: Internet-based self-monitoring offers a potentially feasible and effective method of continuous cognitive monitoring among older adults.

Cortical auditory evoked responses of older adults with and without probable mild cognitive impairment.

OBJECTIVE: Hearing loss has been well-documented as a risk factor for cognitive impairment, but the simple presence of hearing loss is not a sufficient predictor of cognitive decline. Although auditory behavioral research has not revealed an effective indicator of early cognitive impairment, a limited number of studies using cortical auditory evoked potentials (CAEPs) have shown promising evidence of an auditory neurophysiological indicator of early-stage cognitive impairment. The purpose of this study was to examine the P1-N1-P2 complex for indicators of cognitive impairment. METHODS: The latency and amplitude of the P1-N1-P2 complex was measured for two stimuli (pure tone, speech) in two groups: cognitively normal older adults (CNOAs) and older adults with probable mild cognitive impairment (MCI), based on the Montreal Cognitive Assessment. RESULTS: Significantly smaller P2 amplitudes were found for those with probable MCI compared to CNOA across stimulus conditions. Stimulus effects were found for P1 and P2 latency. CONCLUSION: P2 amplitude may be a useful indicator of early-stage cognitive impairment. SIGNIFICANCE: As effective treatments become available, early identification of cognitive impairment can facilitate the prescription of treatment at the earliest juncture. CAEPs have the potential to serve as efficient, non-invasive, cost-effective indicators of future cognitive decline and impairment.

Peripheral Hearing and Cognition: Evidence From the Staying Keen in Later Life (SKILL) Study.

OBJECTIVES: Research has increasingly suggested a consistent relationship between peripheral hearing and selected measures of cognition in older adults. However, other studies yield conflicting findings. The primary purpose of the present study was to further elucidate the relationship between peripheral hearing and three domains of cognition and one measure of global cognitive status. It was hypothesized that peripheral hearing loss would be significantly associated with poorer performance across measures of cognition, even after adjusting for documented risk factors. No study to date has examined the relationship between peripheral hearing and such an extensive array of cognitive measures. DESIGN: Eight hundred ninety-four older adult participants from the Staying Keen in Later Life study cohort were eligible, agreed to participate, and completed the baseline evaluation. Inclusion criteria were minimal to include a sample of older adults with a wide range of sensory and cognitive abilities. Multiple linear regression analyses were conducted to evaluate the extent to which peripheral hearing predicted performance on a global measure of cognitive status, as well as multiple cognitive measures in the domains of speed of processing (Digit Symbol Substitution and Copy, Trail Making Test Part A, Letter and Pattern Comparison, and Useful Field of View), executive function (Trail Making Test Part B and Stroop Color-Word Interference Task), and memory (Digit Span, Spatial Span, and Hopkins Verbal Learning Test). RESULTS: Peripheral hearing, measured as the three-frequency pure-tone average (PTA) in the better ear, accounted for a significant, but minimal, amount of the variance in measures of speed of processing, executive function, and memory, as well as global cognitive status. Alternative measures of hearing (i.e., three-frequency PTAs in the right and left ears and a bilateral, six-frequency PTA [three frequencies per ear]) yielded similar findings across measures of cognition and did not alter the study outcomes in any meaningful way. CONCLUSIONS: Consistent with literature suggesting a significant relationship between peripheral hearing and cognition, and in agreement with our hypothesis, peripheral hearing was significantly related to 10 of 11 measures of cognition that assessed processing speed, executive function, or memory, as well as global cognitive status. Although evidence, including the present results, suggests a relationship between peripheral hearing and cognition, little is known about the underlying mechanisms. Examination of these mechanisms is a critical need to direct appropriate treatment.