Various Domains Of Cognitive Function Research Articles

Unusual patterns of codeswitching in an unbalanced bilingual person with aphasia: effects of language and executive functions impairment

ABSTRACT Background Bilingual individuals with aphasia may exhibit unique patterns of language impairment and recovery. While code-switching (CS) is a common feature of bilingual speech, pathological CS following brain damage can provide insights into the neural mechanisms controlling bilingual language processing. Aims This study aimed to examine language impairment and recovery patterns in IZ, an unbalanced Hebrew-English bilingual with non-fluent aphasia, focusing on the unusual CS behavior observed during his subacute phase of recovery. Methods and procedures IZ underwent language and narrative assessments in both languages during the subacute and chronic phases of recovery. Ten cognitive tests were administered to assess various domains of cognitive function. Language performance was evaluated through naming and syntactic processing tasks in L1-Hebrew and L2-English. The frequency and type of CS were analyzed using the matrix language frame model. Outcomes and results During the subacute phase, IZ displayed significant language deficits in both L1-Hebrew and L2-English, with more severe impairment in L1-Hebrew naming and L2-English syntactic processing. He exhibited frequent involuntary CS, primarily using L1-Hebrew as the matrix language while embedding L2-English content words. Cognitive testing revealed reduced performance across multiple domains. In the chronic phase, IZ showed parallel improvements in both languages, particularly in L1-Hebrew naming and L2-English syntactic processing, along with a marked reduction in CS frequency. Conclusions IZ’s case demonstrates a double dissociation between lexical and syntactic processing across L1 and L2. The results suggest that matrix language selection in bilinguals may be governed by distinct neural mechanisms for each language, with specific brain regions responsible for activating lexical representations. Damage to these regions may lead to pathological CS, as observed in this case. This study underscores the importance of understanding bilingual language control mechanisms in aphasia rehabilitation.

BIRTHPLACE AND COGNITION AMONG US OLDER ADULTS: EVIDENCE FROM THE HARMONIZED COGNITIVE ASSESSMENT PROTOCOL (HCAP)

Abstract Growing evidence shows that place of birth and related circumstances may impose lasting and multiplicative impacts on a host of late-life outcomes; yet how it affects various domains of cognitive function in late-life is less understood. In this paper, we exploit the comprehensive cognitive assessments in the Health and Retirement Study (HRS) Harmonized Cognitive Assessment Protocol (HCAP) and HRS geographic data at birth to determine to what extent birth location measured at the state level is associated with cognitive status in later life for a representative sample of Americans over age 50 (N=3,324). We found that state of birth significantly influenced various cognitive domains later in life (including episodic memory, executive function, attention, visuospatial function, language fluency and orientation); and the regional rankings tended to be highly consistent across the cognitive assessments in each domain. Regression analysis demonstrated that the geographic disparities in cognition across birth states could be partly explained by the late-life differences in socioeconomic statuses. Nevertheless, Shapley decompositions demonstrated that, after accounting for mid-life to late-life factors, state of birth still contributed 20%-30% of the explained variations in cognitive outcomes. Particularly, foreign-born individuals and those born in the southern states tended to score the lowest on average on each of the cognitive tests/domains and can account for most of the explained differences in cognition. These findings suggest that place of birth may have lasting impacts on disparities in cognition later in life. Public policy should play pivotal roles in leveling the playing field in early life.

Correlation between Atherogenic Index of Plasma and Various Domains of Cognitive Function in Type 2 Diabetes Mellitus Patients

Cognitive impairment in patients with Type 2 Diabetes Mellitus (T2DM) is related to the lack of blood supply to the brain. Previous studies showed that the atherogenic index of plasma (AIP) is a predictor of vascular abnormalities, but studies investigating its association with cognitive functions in T2DM patients younger than 60 years remain limited. This study aimed to determine the correlation between AIP and various domains of cognitive function in T2DM patients. This study was a cross-sectional study involving 75 T2DM patients selected using a consecutive sampling technique at Haji Adam Malik General Hospital Medan from July 2021 to January 2022. Cognitive function was examined using the Visual Cognitive Assessment Test Indonesian Version (VCAT-INA) on several cognition domains. The AIP value of each patient was measured and categorized into high (AIP>0.21), intermediate (AIP between >0.11 and ≤0.21), or low (≤0.11). The mean triglyceride level was 176±108.3mg/dl, the HDL-C level was 38.3±12.1mg/dl, and the mean AIP value was 0.191±0.25. The mean score of the VCAT-INA was 21.7±2.3, which was lower than normal. The AIP value showed significant negative correlation with global cognition (r=0.432, p<0.001) and various cognitive domains, namely memory (r=-0.375, p=0.001), attention (r=-0.383, p=0.001), executive function (r=-0.051, p=0.663), visuospatial (r=-0.306, p=0.008), and language (r=-0.352, p=0.002). In short, there is a significant correlation between AIP value and domains of cognitive function, such as memory, attention, visuospatial, and language domains, but not with executive domains.

Disrupted dynamic functional connectivity of hippocampal subregions mediated the slowed information processing speed in late-life depression.

Slowed information processing speed (IPS) is the core contributor to cognitive impairment in patients with late-life depression (LLD). The hippocampus is an important link between depression and dementia, and it may be involved in IPS slowing in LLD. However, the relationship between a slowed IPS and the dynamic activity and connectivity of hippocampal subregions in patients with LLD remains unclear. One hundred thirty-four patients with LLD and 89 healthy controls were recruited. Sliding-window analysis was used to assess whole-brain dynamic functional connectivity (dFC), dynamic fractional amplitude of low-frequency fluctuations (dfALFF) and dynamic regional homogeneity (dReHo) for each hippocampal subregion seed. Cognitive impairment (global cognition, verbal memory, language, visual-spatial skill, executive function and working memory) in patients with LLD was mediated by their slowed IPS. Compared with the controls, patients with LLD exhibited decreased dFC between various hippocampal subregions and the frontal cortex and decreased dReho in the left rostral hippocampus. Additionally, most of the dFCs were negatively associated with the severity of depressive symptoms and were positively associated with various domains of cognitive function. Moreover, the dFC between the left rostral hippocampus and middle frontal gyrus exhibited a partial mediation effect on the relationships between the scores of depressive symptoms and IPS. Patients with LLD exhibited decreased dFC between the hippocampus and frontal cortex, and the decreased dFC between the left rostral hippocampus and right middle frontal gyrus was involved in the underlying neural substrate of the slowed IPS.

Interrelationships between exercise, functional connectivity, and cognition among healthy adults: Asystematic review.

The main purpose of this systematic review was to examine past literature focusing on the potential relationship between exercise (or physical activity or cardiorespiratory fitness [CRF]) and functional brain connectivity in healthy adults. Among the studies meeting this purpose, we also evaluated studies investigating whether, and how, functional connectivity may influence the exercise-cognition relationship. A systematic review was employed through several electronic databases (PsychInfo, PubMed, and Google Scholar) in accordance with PRISMA guidelines. The literature search identified 656 records, and a total of 12 studies met the inclusion criteria. Among these 12 studies, there were 4, 7, and 1 study, respectively, examining the relationship between exercise and frontal lobe connectivity, temporal lobe connectivity, and whole-brain connectivity. Also, 7 studies examined the relationship between functional connectivity and cognitive performance across multiple brain regions as a function of exercise. Existing literature suggests that CRF, habitual physical activity, and varying intensities of acute exercise can strengthen functional connections among a wide variety of regions and subcortical structures of the human brain. These exercise-induced functional connectivity changes within and between specific brain structures/networks supporting cognitive processing may improve various domains of cognitive function. Given these complex associations, a thorough understanding of how functional connectivity plays a mediating role in the exercise-cognition interaction is needed in future studies.

НЕЙРОПСИХОЛОГИЧЕСКИЙ ПРОФИЛЬ У ПАЦИЕНТОВ С ГИПЕРТОНИЧЕСКОЙ ЭНЦЕФАЛОПАТИЕЙ НА ФОНЕ РЕЗИСТЕНТНОЙ АРТЕРИАЛЬНОЙ ГИПЕРТОНИИ

Objective: To assess the severity of CI in relation to the level of RDR to antihypertensive therapy in patients with primary arterial hypertension (AH) and the features of CI on the background of RAH. Methods: A complex of modern clinical, hemodynamic and neuropsychological methods was used to assess RDR to treatment and the severity of CI in groups of patients with high and very high RDR to treatment: the group I – with controlled arterial hypertension (CAH; n=40), the group II – with RAH (n=35). Results: When screening for CI on the Montreal Cognitive Assessment (MoCA) scale, a decrease in the average number of various domains of cognitive function in patients with CAH was found against the background of increased RDR to treatment compared with RAH. The results of the neurodynamic analysis of cognitive function in the Trail Making Test (TMT) indicate the relative sustain of selective attention and information processing speed. However, the established increase in the difference between the part B and part A performance in patients with AH demonstrated a decline in flexible thinking, cognitive control, and programming. The results of the study of regulatory functions showed that frontal dysfunction was observed more often in patients of group II, although the difference was statistically insignificant (p>0.05). Based on the results of speech studies, along with the results of memory impairment testing in the Clock Drawing (CDT) and Free and Cued Selective Reminding – Immediate Recall (FCSRT-IR) tests, a more pronounced decline of semantic memory was found in patients with RAH, indicating the possibility of memory impairment not only due to secondary neurodynamic changes but also due to the neurodegenerative processes. Conclusion: A significant decrease in semantic memory in patients with RAH suggests the possibility of the transformation of cerebral vascular lesions into neurodegenerative ones or their combination. Keywords: Neuropsychological profile, cognitive impairment, hypertensive encephalopathy, risk of developing resistance to treatment, resistant arterial hypertension.

Serum sodium in relation to various domains of cognitive function in the elderly US population

BackgroundRecent evidence suggests that sodium imbalances may be associated with cognitive impairment; however, the association between specific domains of cognition remains unclear. This study examines the association between serum sodium levels and immediate and delayed verbal memory as measured by the CERAD Word Learning Test (CERAD WLT), executive function as measured by the Animal Fluency test (AFT), and sustained attention, working memory, and processing speed as measured by the Digit Symbol Substitution test (DSST) in the elderly population of the US aged 60 and older who participated in the 2011–2014 National Health and Nutrition Examination Surveys (n = 2,541).MethodsCognitive function tests were performed by trained interviewers and sodium levels were measured using indirect ion selective electrode methodology.ResultsAfter adjusting for all covariates, quintiles of CERAD WLT scores showed significant positive associations with log-transformed sodium levels (Immediate recall (IR) β = 4.25 (SE = 1.83, p-value 0.027); Delayed recall (DR) β = 6.54 (SE = 1.82, p-value 0.001)). Compared to normal sodium levels, hyponatremia was significantly associated with lower CERAD WLT-IR (β = -0.34, SE = 0.15, p-value 0.035) and CERAD WLT-DR scores (β -0.48, SE = 0.10, p-value < 0.001) and showed borderline significance with AFT scores (β = = -0.38, SE = 0.19, p-value 0.052). Hypernatremia did not show any significant relationships with cognitive test scores, compared to normal sodium levels.ConclusionsOur cross-sectional study showed that lower sodium levels were associated with cognitive change, especially regarding memory and executive function.

Three types of white matter hyperintensities have different effects on depression and cognitive function in patients with CADASIL

AbstractBackgroundWhite matter hyperintensities (WMH) according to the distance to the ventricle have been associated with different clinical, histopathological, and etiological correlates, which may provide the clues for understanding pathophysiology of many geriatric syndromes associated with WMH. The purpose of this study was to investigate the effects of WMH on depression and cognitive function in patients with CADASIL according to the locations of WMH.Method84 subjects with CADASIL, aged 34–86 years, participated in this study. They underwent comprehensive clinical evaluation, including 3T MRI and genotyping of NOTCH3. With new subclassification of WMH (Kim, 2008), WMH were subclassified into juxtaventricular WMH (JVWMH), periventricular WMH (PVWMH), and deep WMH (DWMH) according to the distance to the ventricle. Lesions were segmented by the lesion prediction algorithm (Schmidt, 2017, Chapter 6.1) as implemented in the LST toolbox version 3.0.0 (www.statistical‐modelling.de/lst.html) for SPM. WMH volume was corrected as a ratio of the WMH volume to total intracranial volume.ResultUsing linear regression model after controlling for age, only JVWMH volume was associated with the scores of geriatric depression scale (GDS) (p=0.027) and CES‐D (p=0.041) among 3 types of WMH. There were no association trends between DWMH volume and scores of GDS (p=0.641) and CES‐D (p=0.427). After controlling age, education and sex, JVMMH volume was associated with poor performances in Categorical Verbal Fluency Test (cVFT) (P=0.013), 15‐item Boston Naming Test (sBNT) (P=0.020), Word List Memory Test (WLMT) (P=0.006), Word List Recall Test (WLRT) (P=0.010), Constructional Recall Test (CRT) (P=0.012), and Trail Making Test A and B (TMT‐A and TMT‐B) (p=0.003, p=0.004). PVWMH volume was associated with poor performances with in cVFT (P=0.027) and WLMT (P=0.031). DWMH volume had no associations with the scores of CERAD neuropsychological tests.ConclusionJVWMH are closely associated with depression and various domains of cognitive function. However, DWMH have no association with both depression and cognitive decline. 3 Types of WMH have different effects on depression and cognitive function in patients with CADASIL.

Associations of olfaction with mild cognitive impairment and cognitive function in older adults: A population‐based study

AbstractBackgroundOlfactory function might be impaired in the early stage of the dementing process, and thus, olfactory test may be useful for identifying elderly persons at an increased risk. However, previous studies that investigate the relationship between olfactory function and cognitive phenotypes have been scarcely conducted among older people living in the rural communities and the associations of olfaction with specific cognitive remains unclear. We sought to examine the relationship of olfactory function with global cognitive ability and various domains of cognitive function among rural‐dwelling Chinese older adults.MethodThis population‐based cross‐sectional study included 3003 dementia‐free participants (age ≥65 years; 57.3% women; 37.7% illiterate) in the baseline examination (March‐September 2018) of the Multidomain Interventions to Delay Dementia and Disability in Rural China (MIND‐CHINA) study. The 16‐item Sniffin’ Sticks identification test (SSIT) was performed to assess olfactory function. Global cognitive function was evaluated with the Chinese version of the Mini‐Mental State Examination (MMSE) and a neuropsychological battery was used to assess memory, language, attention, and executive function. We followed the Petersen’s criteria to define mild cognitive impairment (MCI). Data were analysed with multiple logistic regression and the general linear regression models.ResultOf the 3003 participants, MCI was defined in 335 persons (11.2%). Multiple logistic regression analysis suggested that SSIT score (range 0‐16) was associated with an odds ratio of 0.90 (95% CI 0.87‐0.93) for MCI. Multiple general linear regression analysis showed that SSIT score was significantly associated with the scores of MMSE test (β coefficient=0.07, 95% CI 0.03‐0.11), z‐score of memory (β coefficient=0.28, 95% CI 0.12‐0.45), language (β coefficient=0.35, 95% CI 0.17‐0.52), and attention (β coefficient=0.59, 95% CI 0.38‐0.78), but not with the z‐score of executive function (β coefficient=0.05, 95% CI ‐0.11‐0.22).ConclusionA greater olfactory identification ability is associated with a lower likelihood of MCI and better performances in global cognitive function, attention, memory, and language function, but not in executive function, among Chinese older adults who are living in the rural communities with limited education.

Reduced Retinal Thickness Predicts Age-Related Changes in Cognitive Function.

Currently, there is a lack of biomarkers to identify individuals in the early stages of Alzheimer’s disease (AD). A preponderance of evidence suggests that neurodegenerative processes that affect the brain, may also affect the retina. Using optical coherence tomography (OCT), a non-invasive approach, many have shown thinning of the retina in AD and the developmental precursor to AD, mild cognitive impairment (MCI). However, the relationship between retinal thickness and cognitive function is not entirely clear. This is likely due to the disparity in diagnostic criteria used to determine MCI that does not fully probe the cognitive domains that are particularly vulnerable to aging. This study used a comprehensive neuropsychological assessment involving multiple domains of cognition to determine if retinal thickness correlates with cognitive performance in a normal aged population. In this study, 20 healthy individuals between 60 and 90 years of age were administered neuropsychological assessments probing various domains of cognitive function, and OCT to measure peripapillary retinal nerve fiber layer (RNFL) thickness. We found that RNFL thickness is correlated with neuropsychological performance in multiple cognitive domains (e.g., working memory, psychomotor speed, and executive function). Our work demonstrates a positive correlation between RNFL thickness and several, but not all, domains of cognitive function in a normative aging population. By determining which cognitive domains retinal thickness can predict, this work can help identify individuals at risk or in preclinical stages of AD and other neurodegenerative diseases.

Abstract 38: Prospective Study of Midlife Sedentary Behavior, Physical Activity, and Cognitive Function: The CARDIA Study

Introduction: Evidence suggests moderate to vigorous intensity physical activity (MVPA) has beneficial effects on various domains of cognitive function; however, less than half of adults meet MVPA guidelines. Alternate approaches, such as reducing sedentary behavior (SED) with concurrent increases in light-intensity physical activity (LPA) may resonate more strongly with the adult population. Objective: To determine if accelerometer measured SED, LPA, and MVPA at ages 38-50 years is prospectively associated with measures of cognitive function. Methods: We studied 1,842 Black and White men and women enrolled in CARDIA who participated in the year 20 (2005-06) and year 25 (2010-11) and/or year 30 (2015-16) exams. SED, LPA, and MVPA were measured by the ActiGraph 7164 accelerometer at year 20. Cognitive function tests at the year 25 and 30 exams included the Rey Auditory Verbal Learning Test (RAVLT, memory), Digit Symbol Substitution Test (DSST, processing speed), and Stroop Test (executive function). Compositional isotemporal substitution analysis examined associations of SED, LPA, and MVPA at year 20 with repeated measures (unstructured covariance) of the cognitive function raw test scores at years 25 and 30. Results: In men, substituting 30 minutes of SED with 30 minutes of LPA was associated with a decrease in the RAVLT (-0.05) and DSST (-0.76), and increase in Stroop (0.45) scores, indicating worse performance (see Table ). Substituting SED or LPA with MVPA was associated with an increase in RAVLT (0.15, 0.20) and DSST (1.21, 2.00), and decrease in Stroop (-0.68, -1.17) scores, respectively, indicating better performance. In women, who had higher cognitive function scores than men, substituting SED or LPA with MVPA was associated with worse performance on the Stroop test (0.70, 0.63), contrary to our hypothesis. Conclusions: Statistical substitution of time from lower-intensity activities (SED or LPA) with MVPA, but not SED with LPA, resulted in better cognitive performance in men, but not women, over 10 years.

Preliminary comparison of neuropsychological performance in patients with non-small-cell lung cancer treated with chemotherapy or targeted therapy.

PurposeThis cross-sectional pilot study aimed to compare the effects of chemotherapy and targeted therapy on neuropsychological performance and psychiatric symptoms in patients with non-small-cell lung cancer (NSCLC).Patients and methodsA total of 113 patients with NSCLC were recruited. According to their type of cancer treatment, the patients were classified into chemotherapy (n=40), targeted therapy (n=33), and untreated control (n=40) groups. All participants completed five objective tests measuring various domains of cognitive function, a subjective cognitive functioning scale (Functional Assessment of Cancer Therapy–Cognitive Function; FACT-cog), and the Hospital Anxiety and Depression Scale (HADS) either within 6 months after diagnosis (for the untreated group) or about 18 months after treatment.ResultsOverall, there were no significant intergroup differences in the proportions of patients with abnormal cognitive performance and psychiatric disturbances. Among the untreated NSCLC patients, 35% had impaired performance in at least one cognitive domain, and a comparable finding (30%–35%) was made for the other two treatment groups. The proportion of patients with impaired psychomotor speed was the highest (10%–15%) across various cognitive domains. Moreover, a significant proportion of NSCLC patients (15%–20%) exhibited HADS-defined anxiety and depression disorder. Finally, significant correlations were found between FACT-cog total scores and the HADS Depression subscale across all three groups.ConclusionThis study demonstrated that 1) a substantial proportion of NSCLC patients exhibited cognitive impairments (especially regarding psychomotor speed) and psychiatric disturbances; 2) no significant differences were observed among the three patient groups for any subjective or objective measure of cognitive deficit; and 3) perceived cognitive impairment was significantly associated with depression or anxiety. Prompt treatment of psychiatric disorders to minimize their impact is therefore recommended.

Altered gray matter volume and disrupted functional connectivity of dorsolateral prefrontal cortex in men with heroin dependence.

Chronic heroin use can cause various neuropathological characteristics that may compromise brain function. The present study evaluated the alteration of gray matter volume (GMV) and its resting-state functional connectivity (rsFC) over the dorsolateral prefrontal cortex (DLPFC) among male heroin users. Thirty heroin-dependent men undergoing methadone maintenance therapy and 30 educational-level- and age-matched male controls were recruited for this study. To assess their GMV and rsFC, the participants were evaluated using spoiled gradient echo and gradient-recalled echo planar imaging sequences with a 3-Tesla General Electric MR scanner under resting state. The heroin-dependent men showed lower GMV over the right DLPFC in comparison with the controls. Further evaluation of the rsFC of the right DLPFC revealed a marked decrease in interhemispheric DLPFC connectivity among those with heroin dependence under control of head movement and GMV of the right DLPFC. Although the mechanism remains unclear, the present study shows that chronic heroin use is associated with alteration of morphology as well as rsFC over the right DLPFC. As the DLPFC plays an imperative role in various domains of cognitive function, service providers for heroin users should consider the impacts of possible DLPFC-related cognitive deficits on treatment effectiveness.

Micronutrient interventions on cognitive performance of children aged 5-15 years in developing countries.

It is estimated that more than 200 million young children worldwide fail to reach their potential in cognitive development owing to undernutrition. Numerous studies have assessed the effects of micronutrient supplementation on growth and cognitive development in infants, toddlers and preschoolers. However, micronutrient interventions on the cognitive performance of older children are limited. This article seeks to provide an update on micronutrient interventions and cognitive outcomes among children aged 5-15 years in developing countries. A total of 13 randomized controlled trials published since 2000 were identified. Majority of these studies assessed the effects of micronutrient-fortified foods on various domains of cognitive function. Among key micronutrients assessed were iron, zinc, iodine and vitamin A. This review found a lack of consistency in the impact of micronutrient supplementation on intelligence, long term mental functions and school examination grades of the children. A beneficial effect of micronutrient supplementation on short term memory was more consistently reported. Overall, the evidence from this review for the impact of micronutrients on cognitive performance in older children remains equivocal. In light of the growing interest on the influence of nutrition on cognition, it is important that culturally-appropriate and sufficiently sensitive assessment tools be used for measuring the desired cognitive outcomes that are most likely to be affected by the nutrients under study.

10-Second heart rate variability and cognitive function in old age.

To investigate the cross-sectional and longitudinal associations of 10-second heart rate variability (HRV) with various domains of cognitive function in older participants at risk of cardiovascular disease. We studied 3,583 participants, mean age of 75.0 years, who were enrolled in the Prospective Study of Pravastatin in the Elderly at Risk. From baseline 10-second ECGs, standard deviation of normal-to-normal intervals was calculated as the index of HRV. Four cognitive domains were assessed at baseline and repeated during a mean follow-up period of 3.2 years. Lower HRV at baseline was associated with worse performance in reaction time (mean difference between low third vs high third of HRV = 1.96 seconds, 95% confidence interval [CI] 0.20 to 3.71) and processing speed (-0.57 digits coded, 95% CI -1.09 to -0.05). During follow-up, participants with lower HRV had a steeper decline in processing speed (mean annual change between low third vs high third of HRV = -0.16 digits coded, 95% CI -0.28 to -0.04). There was no difference in annual changes of reaction time or immediate and delayed memory among HRV thirds during follow-up. All these associations remained unchanged after adjustment for medications, cardiovascular risk factors, and comorbidities. Participants with lower 10-second HRV have worse performance in reaction time and processing speed and experience steeper decline in their processing speed, independent of medications, cardiovascular risk factors, and comorbidities.

A systematic review on the association between inflammatory genes and cognitive decline in non-demented elderly individuals

Cognitive impairment, or decline, is not only a feature of Alzheimer׳s disease and other forms of dementia but also normal ageing. Abundant evidence from epidemiological studies points towards perturbed inflammatory mechanisms in aged individuals, though the cause–effect nature of this apparent relationship is difficult to establish. Genetic association studies focusing on polymorphism in and around inflammatory genes represent a viable approach to establish whether inflammatory mechanisms might play a causal role in cognitive decline, whilst also enabling the identification of specific genes potentially influencing specific cognitive facets. Thus, here we provide a review of published genetic association studies investigating inflammatory genes in the context of cognitive decline in elderly, non-demented, samples. Numerous candidate gene association studies have been performed to date, focusing almost exclusively on genes encoding major cytokines. Some of these studies report significant cognitive domain-specific associations implicating Interleukin 1β (IL1β) (rs16944), Tumour Necrosis Factor α (TNFα) (rs1800629) and C-reactive protein (CRP) in various domains of cognitive function. However, the majority of these studies are lacking in statistical power and have other methodological limitations, suggesting some of them may have yielded false positive results. Genome-wide association studies have implicated less direct and less obvious regulators of inflammatory processes (i.e., PDE7A, HS3ST4, SPOCK3), indicating that a shift away from the major cytokine-encoding genes in future studies will be important. Furthermore, better cohesion across studies with regards to the cognitive test batteries administered to participants along with the continued application of longitudinal designs will be vital.

Cigarette smoking and cognitive health in elderly Japanese.

To examine the relationships between smoking status and various domains of cognitive function in community-dwelling elderly subjects. Participants (N = 4348) were asked about smoking status, demographic variables, and lifestyle factors, and underwent multidimensional neurocognitive tests. All analyses were conducted separately by sex. Women never smokers exhibited significantly better scores than past and/or current smokers in some neurocognitive tests. Among men, never smokers had significantly higher scores, such as in the Symbol Digit Substitution Test. Multiple linear regression analysis showed that pack-years (history of smoking) were significantly associated with the Symbol Digit Substitution Test in men. Smoking status may be associated with a decline in processing speed, and this decline varies by sex.

The Impact of Carotid Artery Stenting on Cognitive Function in Patients with Extracranial Carotid Artery Stenosis

The effect of carotid artery stenting (CAS) on cognitive function in patients with extracranial carotid artery stenosis is equivocal. The aim of this study was to examine the impact of CAS on various domains of cognitive function. We performed a meta-analysis of the studies evaluating various domains of cognitive function before and after CAS, namely, (1) global cognition using Mini-Mental State Examination (MMSE) and Rey Auditory Verbal Learning Test (RAVLT), (2) executive function using Trail Making Test (TMT) A or Color Trails Test (CTT) A and TMT B or CTT B, (3) language ability using Boston Naming Test (BNT), (4) memory, (5) attention/psychomotor speed, and (6) functional ability, using various cognitive tests. Pooled weighted mean differences (WMDs) and standardized mean differences (SMDs) with 95% confidence intervals (95% CIs) were appropriately calculated using fixed or random effects models after assessing between-study heterogeneity. Meta-regression analysis was performed with number of patients per study; mean age (years); follow-up (months); proportion of men; proportion of patients with hypertension, diabetes mellitus, hyperlipidemia, smoking, and coronary artery disease; proportion of symptomatic patients; and degree of ipsilateral and degree of contralateral carotid stenosis as covariates. Sixteen studies were eligible, including a total of 626 CAS patients. A statistically significant improvement of global cognition was detected with MMSE (WMD = 0.67, 95% CI = 0.29-1.05, P < 0.001; follow-up = 5.6 months), but not with RAVLT (SMD = 0.45, 95% CI = -0.03 to 0.93, P = 0.07; follow-up = 2.4 months). Significant improvement of memory (SMD = 0.33, 95% CI = 0.11-0.55, P < 0.01; follow-up = 4.1 months) and attention/psychomotor speed (SMD = 0.21, 95% CI = 0.04-0.39, P = 0.02; follow-up = 4 months) was also detected. No statistically significant effect on executive function (TMT A/CTT A and TMT B/CTT B; SMD = 0.08, 95% CI = -0.10 to 0.26, P = 0.39; follow-up = 3.9 months and SMD = -0.02, 95% CI = -0.20 to 0.16, P = 0.82, respectively; follow-up = 3.9 months), language ability (BNT; SMD = 0.24, 95% CI = -0.05 to 0.54, P = 0.10; follow-up = 4 months), and functional ability (SMD = -0.05, 95% CI = -0.25 to 0.15, P = 0.63; follow-up = 3.8 months) was observed. No significant effects of the examined covariates were demonstrated in the meta-regression analyses. CAS may be associated with improvement in global cognition, memory, and attention/psychomotor speed. There was no positive effect on executive function, language, and functional ability, but CAS was not associated with a decline in any area of cognitive function. Future studies in larger groups of patients are probably needed to fully investigate the long-term effect of CAS on cognition in patients with carotid artery stenosis.

Older drivers and rapid deceleration events: Salisbury Eye Evaluation Driving Study

Drivers who rapidly change speed while driving may be more at risk for a crash. We sought to determine the relationship of demographic, vision, and cognitive variables with episodes of rapid decelerations during five days of normal driving in a cohort of older drivers. In the Salisbury Eye Evaluation Driving Study, 1425 older drivers aged 67–87 were recruited from the Maryland Motor Vehicle Administration's rolls for licensees in Salisbury, Maryland. Participants had several measures of vision tested: visual acuity, contrast sensitivity, visual fields, and the attentional visual field. Participants were also tested for various domains of cognitive function including executive function, attention, psychomotor speed, and visual search. A custom created driving monitoring system (DMS) was used to capture rapid deceleration events (RDEs), defined as at least 350milli-g deceleration, during a five day period of monitoring. The rate of RDE per mile driven was modeled using a negative binomial regression model with an offset of the logarithm of the number of miles driven. We found that 30% of older drivers had one or more RDE during a five day period, and of those, about 1/3 had four or more. The rate of RDE per mile driven was highest for those drivers driving <59 miles during the 5-day period of monitoring. However, older drivers with RDE's were more likely to have better scores in cognitive tests of psychomotor speed and visual search, and have faster brake reaction time. Further, greater average speed and maximum speed per driving segment was protective against RDE events. In conclusion, contrary to our hypothesis, older drivers who perform rapid decelerations tend to be more “fit”, with better measures of vision and cognition compared to those who do not have events of rapid deceleration.

Cognition-based interventions for healthy older people and people with mild cognitive impairment

Evidence from some, but not all non-randomised studies suggest the possibility that cognitive training may influence cognitive functioning in older people. Due to the differences among cognitive training interventions reported in the literature, giving a general overview of the current literature remains difficult. To systematically review the literature and summarize the effect of cognitive training interventions on various domains of cognitive function (ie memory, executive function, attention and speed) in healthy older people and in people with mild cognitive impairment. The CDCIG Specialized Register was searched on 30 September 2007 for all years up to December 2005. The Cochrane Library, MEDLINE, EMBASE, PsycINFO and CINAHL were searched separately on 30 September 2007 to find trials with healthy people. These results were supplemented by searches from January 1970 to September 2007 in PsychInfo/Psyndex, ISI Web of Knowledge and PubMed. RCTs of interventions evaluating the effectiveness of cognitive training for healthy older people and people with mild cognitive impairment from 1970 to 2007 that met inclusion criteria were selected. Authors independently extracted data and assessed trial quality. Meta-analysis was performed when appropriate. Only data on memory training could be pooled for analysis. Within this domain, training interventions were grouped according to several outcome variables. Results showed that for healthy older adults, immediate and delayed verbal recall improved significantly through training compared to a no-treatment control condition. We did not find any specific memory training effects though as the improvements observed did not exceed the improvement in the active control condition. For individuals with mild cognitive impairment, our analyses demonstrate the same pattern. Thus, there is currently little evidence on the effectiveness and specificity of memory interventions for healthy older adults and individuals with mild cognitive impairment. There is evidence that cognitive interventions do lead to performance gains but none of the effects observed could be attributable specifically to cognitive training, as the improvements observed did not exceed the improvement in active control conditions. This does not mean that longer, more intense or different interventions might not be effective, but that those which have been reported thus far have only limited effect. We therefore suggest more standardized study protocols in order to maximize comparability of studies and to maximize the possibility of data pooling - also in other cognitive domains than memory.