RESUMO
Several studies have reported subtle differences in cognition between individuals with subjective cognitive decline (SCD) compared to those with normal cognition. This study aimed to (i) identify these differences using discrepancy scores (e.g., categorial-phonemic verbal fluency performance) derived from neuropsychological tests in three cognitive domains (memory: Wechsler's Word List and Digits; executive functions: Stroop and verbal fluency; and language: BNT and ECCO_Senior) and (ii) determine which discrepancy scores are significant for classification. Seventy-five older adults were included: 32 who were labeled SCD+ (age 71.50 ± 5.29), meeting Jessen et al.'s criteria, and 43 in the normal cognition group (SCD-; age 69.81 ± 4.62). Both groups completed a protocol including screening and the specified neuropsychological tests. No differences were found between the groups in their age, education, episodic memory, global cognitive state, or mood. Significant differences between the groups were observed regarding the discrepancy scores derived from BNT (naming) and ECCO_Senior (sentence comprehension). These scores accurately classified participants (71.6%), with ECCO_Senior having a primary role. ROC curves indicated a poor-to-fair model quality or diagnostic accuracy (AUC_BNT = 0.690; AUC_ECCO = 0.722). In conclusion, discrepancy scores in the language domain are important for distinguishing between individuals with SCD and normal cognition, complementing previous findings in this domain. However, given their relatively poor diagnostic accuracy, they should be used with caution as part of a more detailed neuro-psychological assessment.
RESUMO
Repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) are two of the most used non-pharmacological interventions for Alzheimer's Disease (AD). However, most of the clinical trials have focused on evaluating the effects on global cognition and not on specific cognitive functions. Therefore, considering that memory loss is one of the hallmark symptoms of AD, we aim to assess the efficacy and safety of tDCS and rTMS in memory deficits. For that, multilevel random effect models were performed considering the standardized mean difference (SMD) between active and sham stimulation. A total of 19 studies with 411 participants demonstrated positive effects in memory after tDCS (SMD=0.20, p = 0.04) and rTMS (SMD=0.44, p = 0.001). Subgroup analysis revealed that tDCS had greater efficacy when administered in temporal regions (SMD=0.32, p = 0.04), whereas rTMS was superior when applied in frontal regions (SMD=0.61, p < 0.001). Therefore, depending on the brain region of stimulation, both interventions produced a positive effect on memory symptoms in AD patients. Finally, the safety of both techniques was observed in the AD population after the reporting of almost no serious events.
RESUMO
OBJECTIVE: Previous literature has shown that executive functions (EF) are related to performance in memory tasks. The fact that there are no psychometric tests that evaluate these two constructs simultaneously led a group of researchers to develop the Test of Memory Strategies (TSM). Given the potential importance of this instrument for neuropsychological evaluation, in this study, we aimed to evaluate the psychometric properties of the TMS in Portuguese sample. We also examined the effect of aging by exploring profiles of performance on the TMS, comparing young and elderly healthy subjects. METHOD: Total of 135 healthy participants were submitted to a neuropsychological assessment and were divided into four age groups: a group of young adults (25-35 years) and three groups of older individuals (aged 60-69 years, 70-79 years, and 80 or more years). RESULTS: Findings supported the reliability of the TMS scores, based on analyses of internal consistency. As expected, factor analysis of the TMS scores revealed that the test yielded two factors, one capturing EF and the other memory. Correlations with classic neuropsychological tests supported convergent and discriminant validity of the TMS scores. The elderly groups presented more difficulties in creating and mobilizing memory strategies when compared with a younger group, after controlling for the influence of education, although both groups presented increases in performance throughout the five TMS subscales. CONCLUSIONS: The findings suggest that the TMS is an adequate measure to assess memory and EF, simultaneously, presenting adequate psychometric properties for a Portuguese sample.
