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PubMed1989

Auditive and cognitive factors in speech perception by elderly listeners. I: Development of test battery.

This study compares performance of 24 young normal-hearing (aged 18-28 years) and 24 elderly (aged 61-85 years) listeners on auditive (sensitivity, frequency selectivity, and temporal resolution), cognitive (memory performance, processing speed, and divided attention ability), and speech perception tests (at the phoneme, spondee, and sentence level). Its principal aim is to assess whether the tests selected yield meaningful results. The results obtained will be used to reduce the test battery in order to be manageable in a second study on a much larger number of elderly listeners. The relationships between the tests are explored by multivariate statistical methods. The results show that: (a) in young listeners, individual differences in speech perception performance are remarkably small resulting in low correlations between the tests, while in the elderly tests of phoneme, spondee, and sentence perception overlap considerably; (b) speech perception in the elderly seems to be largely determined by hearing loss at the higher frequencies, whereas the effects of other auditive and cognitive factors seem to be relatively small or absent; and (c) performance in the elderly is only partly correlated with age.

Acoustic Stimulation↗

PubMed1990

Auditive and cognitive factors in speech perception by elderly listeners. II: Multivariate analyses.

In part I of this study [van Rooij et al., J. Acoust. Soc. Am. 86, 1294-1309 (1989)], the validity and manageability of a test battery comprising auditive (sensitivity, frequency resolution, and temporal resolution), cognitive (memory performance, processing speed, and intellectual abilities), and speech perception tests (at the phoneme, spondee, and sentence level) were investigated. In the present article, the results of a selection of these tests for 72 elderly subjects (aged 60-93 years) are analyzed by multivariate statistical techniques. The results show that the deterioration of speech perception in the elderly consists of two statistically independent components: (a) a large component mainly representing the progressive high-frequency hearing loss with age that accounts for approximately two-thirds of the systematic variance of the tests of speech perception and (b) a smaller component (accounting for one-third of the systematic variance of the speech perception tests) mainly representing a general performance decrement due to reduced mental efficiency, which is indicated by a general slowing of performance and a reduced memory capacity. Although both components are correlated with age, it was found that the balance between auditive and cognitive contributions to speech perception performance did not change with age.

Adolescent↗

PubMed2001

Spintronics: a spin-based electronics vision for the future.

This review describes a new paradigm of electronics based on the spin degree of freedom of the electron. Either adding the spin degree of freedom to conventional charge-based electronic devices or using the spin alone has the potential advantages of nonvolatility, increased data processing speed, decreased electric power consumption, and increased integration densities compared with conventional semiconductor devices. To successfully incorporate spins into existing semiconductor technology, one has to resolve technical issues such as efficient injection, transport, control and manipulation, and detection of spin polarization as well as spin-polarized currents. Recent advances in new materials engineering hold the promise of realizing spintronic devices in the near future. We review the current state of the spin-based devices, efforts in new materials fabrication, issues in spin transport, and optical spin manipulation.

Journal Article↗

PubMed2006

No cumulative effects for one or two previous concussions.

BACKGROUND: Sports medicine clinicians and the general public are interested in the possible cumulative effects of concussion. OBJECTIVE: To examine whether athletes with a history of one or two previous concussions differed in their preseason neuropsychological test performances or symptom reporting. METHOD: Participants were 867 male high school and university amateur athletes who completed preseason testing with ImPACT version 2.0. They were sorted into three groups on the basis of number of previous concussions. There were 664 athletes with no previous concussions, 149 with one previous concussion, and 54 with two previous concussions. Multivariate analysis of variance was conducted using the verbal memory, visual memory, reaction time, processing speed, and postconcussion symptom composite scores as dependent variables and group membership as the independent variable. RESULTS: There was no significant multivariate effect, nor were there any significant main effects for individual scores. There was no measurable effect of one or two previous concussions on athletes' preseason neuropsychological test performance or symptom reporting. CONCLUSION: If there is a cumulative effect of one or two previous concussions, it is very small and undetectable using this methodology.

Adolescent↗

PubMed2007

Effects of a maximal exercise test on neurocognitive function.

OBJECTIVE: To examine the effects of a maximal exercise test on cognitive function in recreational athletes. DESIGN: A repeated-measures design was used to compare baseline with post-cognitive function and fatigue symptoms after a maximal exercise test. SETTING: Division 1 American Midwestern University, (Michigan State University, Michigan, USA). PARTICIPANTS: 102 male and female recreational athletes. INTERVENTION: Participants in the experimental group (n = 54) were asked to perform a maximal treadmill exercise test to maximal oxygen uptake (VO2 max). Participants in the control group were asked to rest for 15 min. MAIN OUTCOME MEASUREMENTS: All participants were administered a neuropsychological test battery called Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) before and after exercise to measure neurocognitive function and fatigue symptoms. RESULTS: Results revealed a significant group (control, experimental) x time (baseline, post-test 1, post-test 2) interaction for verbal memory composite scores (p = 0.025). Specifically, verbal memory composite scores decreased in the experimental group from baseline to post-test 1 (p = 0.00). These values returned to baseline 3 days after the VO2 max test (p = 0.00). Further analysis on verbal memory composite scores demonstrated significant differences on immediate recall memory (p = 0.00) and delayed recall memory (p = 0.00). No significant differences were observed for visual memory (p = 0.54), motor processing speed (p = 0.68) and reaction time (p = 0.44) composite scores between the experimental and control groups. CONCLUSION: The results of this study suggest that a maximal exercise test attenuated a limiting effect on cognitive function. When utilising a neuropsychological test battery to evaluate a patient who has sustained a head injury, the test should not be administered immediately after a practice or a game session.

Cognition↗

PubMed2004

Temporal relation between depression and cognitive impairment in old age: prospective population based study.

OBJECTIVE: To examine the temporal relation between depression and cognitive impairment in old age. DESIGN: Prospective, population based study with four years of follow up. SETTING: City of Leiden, the Netherlands. PARTICIPANTS: 500 people aged 85 years at recruitment. MAIN OUTCOME MEASURES: Annual assessments of depressive symptoms (15 item geriatric depression scale), global cognitive function (mini-mental state examination), attention (Stroop test), processing speed (letter digit coding test), and immediate and delayed recall (12 word learning test). RESULTS: At 85 years old, participants' depressive symptoms and cognitive impairment were highly significantly correlated (P < 0.001). During follow up, an accelerated annual increase of depressive symptoms was associated with impaired attention (0.08 points (95% confidence interval 0.01 to 0.16)), immediate recall (0.17 points (0.09 to 0.25)), and delayed recall (0.10 points (0.02 to 0.18)) at baseline. In contrast, depressive symptoms at baseline were not related to an accelerated cognitive decline during follow up (P > 0.05). CONCLUSION: Caregivers should be aware of the development of depressive symptoms when cognitive impairment is present. However, the presence of depression only does not increase the risk of cognitive decline.

Aged↗

PubMed2005

Cognitive patterns and progression in multiple sclerosis: construction and validation of percentile curves.

BACKGROUND AND OBJECTIVES: Rate and pattern of progression of cognitive decline in multiple sclerosis (MS) has not been clearly identified. The present study aimed to identify correlations between cognitive tests and disease duration, construct longitudinal cognitive curves, and assess pattern of change over time. METHODS: The Neuropsychological Screening Battery for Multiple Sclerosis was administered in 150 consecutive MS patients, and tests that correlated with disease duration were identified. Percentile curves were constructed and the pattern of cognitive decline over time explored. The cognitive curves were validated in an additional group of 83 patients with MS. RESULTS: Three of four measures of the spatial recall test (SPART 7/24), and the paced auditory serial addition task for two seconds (PASAT 2'), correlated with disease duration. These tests were used to construct cross-sectional curves identifying the pattern of cognitive decline over time in the MS population. On the basis of this cross-sectional analysis, the earliest cognitive decline occurred in the SPART 7/24 trials 1-5 between one and three years from onset, followed by decline in the SPART delayed recall between three and seven years, and then by decline in the PASAT 2' after seven years from onset. CONCLUSIONS: Verbal fluency and verbal memory appear to be affected earliest in MS. The pattern of cognitive decline is further characterised by a decrease in visuospatial learning, followed by delayed recall, and then by attention and information processing speed. Cognitive percentile curves can be used to evaluate the pattern of progression and identify patients at increased risk.

Adolescent↗

PubMed1987

Psychomotor slowing and subcortical-type dysfunction in depression.

Elderly patients with major depression and normal controls completed the Sternberg short-term memory scanning procedure and WAIS Digit Symbol. Depressed patients demonstrated psychomotor slowing on both tasks, but normal response latency as a function of memory set size on the Sternberg procedure. While cognitive-behavioural slowing may be observed in both depressive illness and subcortical neurological disorders, a normal rate of processing information centrally appears to distinguish depression from certain of these disorders. Psychomotor slowing in the presence of normal information processing speed might be explained by a deficit in motivational state associated with depression.

Aged↗

PubMed1991

Increased radiation dose at mammography due to prolonged exposure, delayed processing, and increased film darkening.

Four single-emulsion films introduced over the past 2 years--Du Pont Microvision, Fuji MiMa, Konica CM, and Eastman Kodak OM--were compared with Eastman Kodak OM SO-177 (Min-RE) film to evaluate their varying effects on mean glandular dose of reciprocity law failure due to prolonged exposure, delayed processing, and increased film darkening as a result of increased radiation exposure to improve penetration of glandular tissue. Exposures over 1.3 seconds led to increased radiation doses of 20%-30%. Delays in processing of 6 hours decreased processing speed by 11%-32% for all films except Du Pont Microvision. Optical density increases of 0.40 required 20%-30% more skin exposure for all five films. Optimal viewing densities were also evaluated and found to be different for each of the five films. Mammographers need to be aware of these differences in mammographic films to achieve maximum contrast at mammography.

Breast↗

PubMed2004

Associations between serum testosterone fall and cognitive function in prostate cancer patients.

Data on the association between cognition and testosterone levels in elderly men are inconclusive. Androgen deprivation therapy is commonly used in the treatment of prostate cancer with the aim of achieving castration levels of serum testosterone. The study group comprised 26 elderly men (mean age 65 years) with newly diagnosed prostate cancer. Cognitive testing was done at baseline and at 6 and 12 months on androgen deprivation therapy. Cognitive performances were evaluated using verbal, visuomotor, and memory tests as well as tests of processing speed and attention. Castration levels of testosterone were achieved in all patients by 6 months. Significant associations between cognitive performances and testosterone decline were documented: visuomotor slowing, slowed reaction times in some attentional domains including working memory and impaired hit rate in a vigilance test, impaired delayed recall and recognition speed of letters, but improvement in object recall. The results suggest selective associations between testosterone decline and cognition. Documentation of cognitive performance with changes in serum testosterone levels has substantial implications for informed patient support in prostate cancer.

Aged↗

PubMed2003

Profile of neuropsychological deficits in older stroke survivors without dementia.

BACKGROUND: Few studies have examined the profile of cognitive impairments in older stroke patients without dementia. METHOD: A standardized evaluation including a detailed neuropsychological assessment [Cambridge Examination for Mental Disorders in the Elderly--cognitive subscale (CAMCOG)] and computerised tests of attention and working memory from the Cognitive Drug Research battery were undertaken in 150 stroke survivors of >75 years of age and 30 elderly controls. RESULTS: The stroke survivors without dementia had significantly greater overall impairment on the CAMCOG, as well as significantly greater impairment in memory, simple reaction time, choice reaction time (CRT), vigilance accuracy, CRT variability, spatial working memory reaction time (SWMRT) and numerical working memory than the elderly controls (e.g. CRT [up] 33%, SWMRT [up] 61%, memory [down] 11%). CONCLUSION: Impairments of cognitive processing speed, working memory and executive functions are frequent in elderly stroke patients without dementia and represent the main cognitive components of early cognitive impairments.

Aged↗

PubMed2003

MRI study of caudate nucleus volume in Parkinson's disease with and without dementia with Lewy bodies and Alzheimer's disease.

OBJECTIVE: To compare whole brain and caudate volume on MRI in subjects with Parkinson's disease without cognitive impairment (PD), Parkinson's disease with dementia with Lewy bodies (PD + DLB), Alzheimer's disease (AD) and normal control subjects. To examine the relationship between caudate volume and cognitive impairment, depression and movement disorder. METHOD: Whole brain and caudate volumes were segmented from volumetric 1.5-tesla magnetic resonance imaging (MRI) scans of older subjects with PD (n = 28; mean age 75.5 years), PD + DLB (n = 20; 73.0 years), AD (n = 27; 77.5 years) and normal controls (n = 35; 74.9 years). RESULTS: Subjects with AD had significantly reduced whole brain and caudate volume compared to controls and those with PD. Caudate atrophy in AD was proportionate to whole brain atrophy. There were no significant differences in whole brain or caudate volume between controls, PD and PD + DLB. There were no significant correlations between caudate volume and either global cognitive function, executive performance or processing speed. CONCLUSIONS: Caudate atrophy occurs in AD but not PD without dementia. Caudate atrophy is not regionally specific but part of generalised brain volume loss. Structural changes in the caudate, as assessed by in vivo MRI, do not appear to contribute to the cognitive impairment observed amongst patients with PD, PD + DLB or AD. Results indicate that the executive and attentional dysfunctions associated with PD and DLB are unlikely to be a direct and specific consequence of caudate atrophy as assessed on MRI.

Aged↗

PubMed2003

Hyperintensities and fronto-subcortical atrophy on MRI are substrates of mild cognitive deficits after stroke.

AIM: The current study determines the MRI correlations of the early neuropsychological post-stroke cognitive deficits. METHOD: Detailed neuropsychological assessments (attention and working memory) were undertaken in 50 stroke survivors >75 years of age [38 with ageing-associated cognitive decline (AACD)] and 15 age-matched controls. A 1.5-tesla General Electric MRI scanner was used. Standardized visual ratings were undertaken of white matter hyperintensities (WMH). Grey matter volumes were assessed using voxel-based morphometery. RESULTS: Associations were identified between processing speed and executive function and the severity of WMH in key areas. In addition, atrophy in the fronto-subcortical circuits was associated with AACD. CONCLUSION: Attentional and executive impairments are underpinned by WMH in fronto-striato-thalamo-frontal circuits. Frontal atrophy is identified as a novel substrate of cognitive decline in stroke patients.

Aged↗

PubMedDate not supplied

An automatic method to quantify the vibration properties of human vocal folds via videokymography.

The study offers an automatical quantitative method to obtain vibration properties of human vocal folds via videokymography. The presented method is based on image processing, which combines an active contour model with a genetic algorithm to improve detecting precision and processing speed, can accurately extract the vibration wave in videokymograms and quantify the vibration properties in terms of eight typical parameters automatically. To verify the precision of the proposed algorithm, an indirect simulation setup of vocal folds has been performed. The verification result shows that the relative error of the entire simulation system is less than 5%. Applying the method to analyzing hundreds of videokymograms from 12 subjects, the result indicates that the vibration characteristics of vocal folds can be recognized more exactly, and diseases of the vocal folds can be diagnosed quantitatively.

Algorithms↗

PubMedDate not supplied

Biological age and 12-year cognitive change in older adults: findings from the Victoria Longitudinal Study.

BACKGROUND: Although recent cross-sectional findings indicate that markers of biological age (BA) mediate chronological age (CA) differences in cognitive performance, little is known about their influence on actual cognitive changes. OBJECTIVE: The purpose of this investigation is to examine CA and BA as predictors of 12-year cognitive change in a longitudinal sample of older adults. METHODS: Data from the Victoria Longitudinal Study (VLS) were examined for 125 adults between 67 and 95 years of age. Biomarkers, including visual and auditory acuity, grip strength, peak expiratory flow, blood pressure, and body mass index, were submitted to a factor analysis and a composite BA variable was computed based on factor loadings. Intraindividual change across 5 waves of measurement (3-year intervals) was examined as a function of CA and BA for 5 cognitive domains: verbal processing speed, working memory, reasoning, episodic memory, and semantic memory. RESULTS: The latent structure of biomarkers was consistent with previous investigations of functional age and a common factor view of biological aging. Results of hierarchical linear modeling showed that BA predicted actual cognitive change (decline) independent of CA. CONCLUSIONS: As a predictor of cognitive performance in late life, CA is a proxy for biological and environmental influences. We have shown that biological influences are independent predictors of actual cognitive change in older adults. This supports the view that cognitive decline is not due to aging per se, but rather is likely due to causal factors that operate along the age continuum.

Aged↗

PubMedDate not supplied

Effects of aging on visual attentional focusing.

BACKGROUND: Visual attentional performance is affected by aging, but there are methodological barriers to the understanding of this phenomenon that are due, above all, to the concomitant deterioration of sensory or central factors such as visual acuity and information processing speed. OBJECTIVE: The aim of the present study was to verify the effects of aging on visual attentional focusing by analyzing the space- and object-based components as well as the exogenous and endogenous dimensions of the attentional allocation. METHODS: Focusing of visual attention was investigated in 14 youngsters, 14 younger adults and 14 older adults (age ranges 12-15, 24-38 and 60-75 years, respectively). In two discrimination reaction time (RT) experiments, attention was cued by means of spatial cues of different size followed by compound stimuli at a shorter (150 ms) and a longer (500 ms) stimulus-onset asynchrony (SOA). The compound stimuli contained a predefined target letter at a local or global level. RESULTS: Older adults showed generally slower RTs and higher rates of delayed responses than younger individuals and reduced discrimination speed of local objects at 150-ms SOA, particularly when attention was invalidly cued to focus at a larger spatial scale. CONCLUSIONS: This pattern of results suggests that aging causes a dysfunction of the space-based and the object-based components of the attentional 'zooming in'. Such information may be of practical relevance for developing attentional training programs for older adults.

Adolescent↗

PubMed2006

Neurocognitive function in adults with growth hormone deficiency.

The clinical condition of growth hormone deficiency (GHD) as a consequence of pituitary or hypothalamic disease has been associated with reduced cognitive performance. In several studies, neuropsychological assessment has been performed in adults with GHD both before and after growth hormone (GH) replacement therapy. Interpretation of the available data is complicated by the variation in patient selection as well as the neuropsychological tests used in such studies. Most of the available studies indicate that GHD can lead to small, but clinically relevant changes in memory, processing speed and attention. Some of these changes may be reversed by GH replacement, although the number of reliable intervention studies is limited. In addition to the possible clinical relevance of neuropsychological improvement following GH replacement in patients with GHD, the observed findings may be of interest for studies in neurocognitive performance in other conditions associated with changes in the activity of the somatotrophic axis, and in the understanding of underlying pathophysiological mechanisms.

Adult↗

PubMed2026

Plasma von Willebrand Factor and ADAMTS13 Interact With APOE-ε4 in Predicting Longitudinal Brain Atrophy and Cognitive Decline Over a 9-Year Follow-Up.

BACKGROUND: Von Willebrand factor (VWF) and ADAMTS13 (a disintegrin and metalloproteinase with thrombospondin type 1 motif, 13) are linked to dementia risk, and limited evidence suggests apolipoprotein E (APOE)-ε4 alters VWF release. This study assessed whether baseline VWF and ADAMTS13 levels predict neurodegeneration and cognitive decline and evaluated effect modification by APOE-ε4 carriership. METHODS: Vanderbilt Memory and Aging Project cohort participants (n=332, 73±7 years, 59% male) completed serial blood draw, neuropsychological assessment, and brain magnetic resonance imaging over 6.4 years (range 1.4-9.7 years). Baseline plasma VWF and ADAMTS13 levels were quantified using mass spectrometry and Olink. Fully adjusted linear mixed-effects models related protein×time and protein×APOE-ε4×time interaction terms to longitudinal brain magnetic resonance imaging and neuropsychological outcomes. RESULTS: Lower baseline ADAMTS13 predicted faster declines in language (β=0.11, P=0.01), information processing speed (β=0.27, P=0.001), executive function (β=0.01, P=0.03), episodic memory (β=0.01, P=0.03), and visuospatial ability (β=0.11, P=0.001) and faster increases in global (β=-0.29, P=0.01) and frontal (β=-0.17, P=0.01) white matter hyperintensity volumes. Associations between ADAMTS13 and faster rates of cognitive decline and white matter injury were driven by APOE-ε4 carriers. Models relating VWF to longitudinal outcomes were null. APOE-ε4 interacted with VWF on longitudinal gray matter volumetric outcomes, such that faster rates of global gray matter atrophy were observed with higher baseline VWF levels among APOE-ε4 noncarriers only (β=-1530.5, P<0.001). CONCLUSIONS: ADAMTS13 shows promise as a potential plasma biomarker for brain aging outcomes, but additional research is warranted to understand the performance of VWF in the presence versus absence of an APOE-ε4 allele.

Humans↗