The most common cause of vascular cognitive impairment not demented (VCIND) is cerebral small vessel disease leading to diffuse subcortical white matter lesions. While many studies indicate that the core cognitive features of VCIND are executive dysfunction and impaired processing speed, this finding is not always consistent, and may be partially dependent on the comparison group applied. Hence, we undertook two systematic meta-analytic reviews on neuropsychological test performance across eight cognitive domains: between VCIND and healthy controls (data from 27 studies), and between VCIND and non-vascular mild cognitive impairment (nv-MCI; data from 20 studies). Our quantitative synthesis of the research literature demonstrates that individuals with VCIND show weaknesses across all cognitive domains relative to healthy controls, with the greatest impairment in the domain of processing speed (Md = -1.36), and the least affected being working memory (Md = -.48) and visuospatial construction (Md = -.63). When compared directly with nv-MCI, individuals with VCIND had significantly greater deficits in processing speed (Md = -.55) and executive functioning (Md = -.40), while those with nv-MCI exhibited a greater relative deficit in delayed memory (Md = .41). Our analyses indicate that disruption to subcortical white matter tracts impairs more cognitive processes than is typically thought to be directly related to the fronto-subcortical network. The data also suggest that differing brain aetiologies can be responsible for similar cognitive profiles. Although the findings do not evince diagnostic value, they allude to the interconnectivity of disparate cognitive processes and call for further research on the behavioural outcome of network disruption.

Our results replicate findings of greater RT inconsistency in older adults and reveal that executive functioning is related to tau in adults aged 75-85. These results support literature identifying tau as a marker of cognitive control, which deteriorates in old age.

Previous studies have observed poorer working memory performance in individuals with amnestic mild cognitive impairment than in healthy older adults. It is unclear, however, whether these difficulties are true only of the multiple-domain clinical subtype in whom poorer executive functioning is common. The current study examined working memory, as measured by the self-ordered pointing task (SOPT) and an n-back task, in healthy older adults and adults with single-domain amnestic mild cognitive impairment (aMCI). Individuals with single-domain aMCI committed more errors and required longer to develop an organizational strategy on the SOPT. The single-domain aMCI group did not differ from healthy older adults on the 1-back or 2-back, but had poorer discrimination on the 3-back task. This is, to our knowledge, the first characterization of dynamic working memory performance in a single-domain aMCI group. These results lend support for the idea that clinical amnestic MCI subtypes may reflect different stages on a continuum of progression to dementia and question whether standardized measures of working memory (span tasks) are sensitive enough to capture subtle changes in performance.

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Objectives Amnestic mild cognitive impairment (aMCI), a prodromal stage of Alzheimer’s disease and other dementias, is characterized by episodic memory impairment. Recent evidence has shown inhibitory control deficits in aMCI, but the extent of these deficits across inhibitory domains (i.e., response inhibition and interference control) and aMCI subtypes (i.e., single- versus multiple-domain) remains unclear. Few studies have included response time intra-individual variability (RT IIV) in these efforts. The aim of this study was to compare response inhibition and interference control between aMCI subtypes using measures of accuracy, mean RT, and RT IIV. Method We report data from 34 individuals with single-domain aMCI (sdaMCI, 66–86 years), 20 individuals with multiple-domain aMCI (mdaMCI, 68–88 years), and 52 healthy controls (64–88 years) who completed tasks of response inhibition (Go-NoGo) and interference control (Flanker). Group differences in accuracy, mean RT, and RT IIV were examined for both tasks. Results Individuals with mdaMCI had higher RT IIV than the other groups on both tasks. In RT IIV, we observed an interference control deficit in mdaMCI and sdaMCI relative to healthy controls, a finding not observed through accuracy or mean RT. Discussion RT IIV may detect subtle differences in inhibition deficits between aMCI subtypes that may not be evident with conventional behavioral measures. Findings support the supplementary use of RT IIV when assessing early executive function deficits.

The pattern of early recovery followed by decline in executive control function is consistent with growing evidence that moderate-severe TBI is a progressive and degenerative disorder. Given the responsiveness to treatment of executive control deficits, elucidating the trajectory and underpinnings of inconsistent behavioral responding may reveal novel prognostic and clinical management opportunities.

Objectives: To identify novel targets for neurorehabilitation of people with a remote history of multiple concussions by: (1) comprehensively characterizing neuropsychiatric and cognitive functioning in former professional football players, with a focus on executive functions; (2) distinguishing concussion-related findings from pre-morbid/cohort characteristics of professional football players; and, (3) exploring the relationship between executive functions and neuropsychiatric symptoms. Participants: Sixty-one high-functioning former professional football players and 31 age- and sex-matched control participants without history of concussion or participation in contact sports. Design: Between-groups analyses. Main measures: Neuropsychiatric . Personality Assessment Inventory (PAI) clinical scales plus the Aggression treatment consideration scale; the Mini International Neuropsychiatric Interview (MINI). Cognitive . Comprehensive clinical neuropsychological battery assessing domains of verbal and visuospatial attention; speed of processing and memory; current and estimated pre-morbid IQ; and, executive functioning, including two experimental measures that were novel for this population (i.e., response inhibition and inconsistency of responding on a go/no-go task). Results: (1) Compared to control participants, former professional football players scored significantly higher on the PAI Depression, Mania, and Aggression scales, and significantly lower on response inhibition. (2) Relative to controls, former players with >3 concussions ( 6 1 ), but not former players with ≤ 3 concussions ( 2 0 ), showed (i) significantly higher scores on the PAI Depression scale, (ii) significantly more MINI clinical diagnoses overall, and manic/hypomanic episodes specifically, and (iii) significantly poorer executive function. (3) Mediation analysis revealed that concussion exposure had a significant indirect effect on PAI Depression, Mania, and Aggression via inconsistency of responding on the go/no-go task. Conclusions: Notable impairments to neuropsychiatric functioning and worse performance on a sensitive experimental measure of executive function were observed; these were related to both concussion history and pre-morbid (cohort) factors. Therefore, neuropsychiatric and executive functioning should be carefully assessed in those with a remote history of multiple concussions. Moreover, former players' neuropsychiatric symptoms were associated with inconsistency of responding; this suggests that treatments targeted at response inconsistency could help to mitigate neuropsychiatric dysfunction.

Although it is currently not known whether early assessment and treatment of hemispatial neglect improves rehabilitation outcome, identification in the acute phase of post stroke is important for nursing, counseling families, and planning intervention strategies. Previous tests of neglect either fail to detect mild forms of neglect or are too lengthy for use at the bedside. We tested and selected an efficient, small battery of tests to address this gap. Two hundred and twenty-four stroke patients completed the Sunnybrook Neglect Assessment Procedure (SNAP). Normal performance was determined from a population of 100 normal elderly volunteers. The SNAP was shown to be a highly reliable and valid instrument. Factor analysis showed good internal consistency, suggesting that performance on each subtest is positively correlated with the others. The SNAP is a useful and reliable tool to assess neglect at the bedside in acute stroke patients.