A network psychometric approach to neurocognition in early Alzheimer's disease

A Graph Theory Approach to Clarifying Aging and Disease Related Changes in Cognitive Networks

“…Given the corroboration of this finding by previous network analyses ( Tosi et al, 2020 ; Ferguson, 2021 ), and the fact that both these domains are known to be significantly affected in Alzheimer’s disease ( McKhann et al, 2011 ), the graphs presented here can be said to reflect accurate neuropsychological profiles that are characteristic of this type of neurodegeneration. Furthermore, in line with the findings of Ferguson (2021) , similarities between the graph of the aMCI and Alzheimer’s dementia groups demonstrate that this pattern may be discernible even in the early stages of disease, being clearly distinguishable from the profile of healthy older individuals. In an extension of Ferguson’s findings, the lack of similarity between the networks of the Alzheimer’s dementia group and the naMCI patients, who may be more likely to represent the prodromal stages of a differing neurodegenerative condition ( Petersen et al, 2001 ; Petersen, 2004 ; Busse et al, 2006 ; Petersen and Negash, 2008 ; Ferman et al, 2013 ), suggests that cognitive network analysis may be a useful technique for characterizing differential cognitive profiles between disparate neurological populations ( Garcia-Ramos et al, 2016 ; Kellermann et al, 2016 ; Jonker et al, 2019 ; Tosi et al, 2020 ) not only in the dementia stages of disease but, furthermore, in the prodromal stages.…”

“…Between the stages of healthy aging, however, it was expected that crystallized cognitive functions such as semantic processing ( Cattell, 1971 ) may have a more prominent role in the network structure of older adults compared with younger groups, while substantial differences in network properties relating to tests of executive functioning may be further apparent, in line with age-related declines in this domain ( Harada et al, 2013 ). Furthermore, in accordance with the findings of Ferguson (2021) and previous neuroimaging analyses ( Rashidi-Ranjbar et al, 2020 ), patients with an amnestic mild cognitive impairment, and not those with a non-amnestic impairment, were expected to present with a network composition closely aligned to patients diagnosed with Alzheimer’s dementia.…”

“…Regarding modularity, of particular interest was the finding that the discernible modules in the graphs of the aMCI and dementia groups were clearly separated by their relation to language and memory function, a characteristic identified in Alzheimer’s disease in the study by Tosi et al (2020) and in both aMCI and Alzheimer’s dementia patients in the study by Ferguson (2021) that was not apparent among the healthy older participants or the naMCI patients. Given the corroboration of this finding by previous network analyses ( Tosi et al, 2020 ; Ferguson, 2021 ), and the fact that both these domains are known to be significantly affected in Alzheimer’s disease ( McKhann et al, 2011 ), the graphs presented here can be said to reflect accurate neuropsychological profiles that are characteristic of this type of neurodegeneration. Furthermore, in line with the findings of Ferguson (2021) , similarities between the graph of the aMCI and Alzheimer’s dementia groups demonstrate that this pattern may be discernible even in the early stages of disease, being clearly distinguishable from the profile of healthy older individuals.…”

“…Although this study demonstrated a number of qualitative differences in network characteristics between the healthy group and those with neurological disease, the results were limited in terms of quantitative differentiation between aging and disease-related cognitive network topology. Ferguson (2021) took the approach a step further, comparing the cognitive networks of healthy older adults to those with early Alzheimer’s type dementia and amnestic mild cognitive impairment, who may represent a prodromal stage of disease. This study was able to corroborate Tosi et al’s findings, demonstrating substantial evidence for reorganization of the cognitive network in even the earliest stages of Alzheimer’s disease.…”

A Network Analysis of the Relationship among Reading, Spelling and Maths Skills

“…This type of analysis has been used to investigate different phenomena. In psychology, this have proved useful for studying personality and psychopathology [ 24 , 32 , 33 , 34 , 35 , 36 ], experimental psychology [ 37 ], and also for assessing the correlations across neuropsychological test performances [ 38 , 39 ]. The principle behind the networks is simple: take a set of variables of interest (called nodes) and identify their direct and indirect relationships (named edges).…”