Normative data for a computer-assisted version of the auditory three-consonant Brown-Peterson paradigm in the elderly French-Quebec population

The Auditory Consonant Trigram (ACT) Test: A norm updating study for university students

The Auditory Consonant Trigram (ACT) Test is accepted as a pure measurement of verbal working memory, but its norm study and psychometric properties have not been sufficiently researched. This study aims to update the norm data of the ACT, validity and reliability studies of which have been previously conducted on an adult Turkish sample, on a broader young sample and in a way that would end some methodological limitations. For this purpose, the data is collected from 304 voluntary healthy young adults (aged 18-26, 152 females-152 males). According to the results, a difference is found among all delay intervals. While the test scores decrease in females as delay interval increases, there is no difference in males between the delay intervals of 9 and 18 sec. While there is no difference between the genders for very short delay intervals (0-3 sec), males show a more successful performance than females as the delay interval increases (9-18 sec). Males are also more successful than females in terms of total test scores of the ACT. In this respect, it is concluded that the ACT measurement of working memory with a total score reliability coefficient of 0.75 is reliable.

Characterizing mild cognitive impairment to predict incident dementia in adults with bipolar disorder: What should the benchmark be?

Objective: Although mild cognitive impairment (MCI) is generally considered a risk state for dementia, its prevalence and association with dementia are impacted by the number of tests and cut-points used to assess cognition and define "impairment," and sources of norms. Here, we investigate how these methodological variations impact estimates of incident dementia in adults with bipolar disorder (BD), a vulnerable population with pre-existing cognitive deficits and increased dementia risk. Method: Neuropsychological data from 148 adults with BD and 13,610 healthy controls (HC) were drawn from the National Alzheimer's Coordinating Center. BD participants' scores were standardized against published norms and again using regression-based norms generated from HC within the same catchment area as individual BD patients ("site-specific norms"), varying the number of within-domain tests (one vs. two) and the cut-points (-1 vs. -1.5 SD) used to operationalize MCI. Results: Site-specific norms were more sensitive to incident dementia (88.6%-94.3%) than published norms (74.3%-88.6%), but only when using a "single test" definition of impairment. Specificity (22.1%-74.3%), accuracy (37.8%-68.9%), and positive predictive values (26.1%-38.3%) were overall poor. Applying a "single test" definition of impairment resulted in better negative predictive values using site-specific (92.3%-93.3%) than published norms (83.6%-86.2%), and a substantial increase in relative risk of incident dementia relative to published norms. Conclusions: Neuropsychologists should define "impairment" as scores below -1.0 or -1.5 SD on at least two within-domain measures when using published norms to interpret cognitive performance in adults with BD.

[Revue systématique des tests cognitifs validés et/ou ayant des normes de référence pour la population canadienne francophone âgée]

Il est essentiel d'utiliser des tests cognitifs ayant été validés et détenant des normes de référence auprès de la population cible, puisque les réalités culturelles et linguistiques différentes entre l'échantillon de validation ou auprès duquel les normes ont été créées et la population cible peuvent affecter les résultats. Cette revue systématique vise à recenser et décrire les tests cognitifs (incluant tests, questionnaires et grilles d'observation) validés et/ou présentant des normes sur la population âgée canadienne francophone. Au total, 46 articles ont été sélectionnés. Cette revue recense 9 tests validés, 20 tests avec normes de référence et 18 tests validés et avec normes, couvrant la majorité des domaines cognitifs (fonctions mnésiques, attentionnelles, exécutives, perceptivo-motrices et langagières), excepté la cognition sociale. La quasi-totalité des échantillons ont été recrutés au Québec. Les tests relevés présentent majoritairement des indices psychométriques satisfaisants et généralement des normes considérant l'âge, le sexe et l'éducation. Cette revue systématique permettra aux cliniciens et chercheurs canadiens en vieillissement d'orienter optimalement leurs choix de tests cognitifs.

The neural correlates of interference control dysfunction of working memory in major depressive disorder: An event-related potential study

Interference control function is a key function in a series of specific functions of working memory (WM), which is usually impaired in patients with major depressive disorder (MDD). Event-related potentials (ERPs) have advantages in exploring the neural processing of interference control and WM impairment, and therefore, it is helpful to further understand the neural mechanism of MDD. In the present study, 44 patients with MDD and 44 age- and sex-matched healthy controls (HCs) were recruited. All participants completed a 4-gradient difficulty Brown-Peterson task (BPT), whose difficulty was manipulated by changing the demand of interspersed distraction tasks. High-density EEG was simultaneously recorded. The hit rate and reaction time (RT) toward the target stimulus as well as the underlying ERP features were analyzed. The results showed that, when compared with HCs, MDD patients had significantly lower hit rates and longer RTs among all four difficulties of BPT. For ERP components, no significant between-group difference was found in either N100 or P200 average amplitudes; however, the centroparietal late positive potential (LPP) amplitude of both MDD group and HC group decreased with the increase of BPT difficulty, despite the pattern of the HC group was relative moderate. For both groups, the LPP amplitude was significantly smaller in high-order difficult BPT tasks than in low-order difficult tasks. Moreover, LPP amplitude in high-order difficult tasks was much smaller in MDD group than that of HC group. Our findings suggest that failure to control interference well may play a critical role in the impairment of WM in patients with MDD, and provided new evidence that the neural correlates of interference control dysfunction of WM in MDD.