Neuronal efficiency following n-back training task is accompanied by a higher cerebral glucose metabolism

No effects of the theta-frequency transcranial electrical stimulation for recall, attention control, and relation integration in working memory

“…The fact that the performance in the sham session strongly but negatively predicted performance in the stimulation sessions, together with fact that after subtracting the sham performance the resulting difference in the frontal and parietal stimulation sessions correlated strongly positively, indicate that actually the individual performance across sessions was exceptionally stable. As the recall (Unsworth and Engle, 2007 ), the antisaccade (Draheim et al, 2021 ), and the graph mapping task (Jastrzebski et al, 2020 ) are known as highly reliable and valid markers of individual differences in WM capacity, scores on these tasks may reflect individual effectiveness of neurocognitive mechanisms underlying such capacity, which might be difficult to change with a relatively simple tACS intervention (see analogous failures to increase WM capacity and fluid intelligence using cognitive training protocols; Sala et al, 2019 ; Ripp et al, 2022 ). At the same time, the n-back and the change detection tasks, as less reliable and less indicative of individual differences in WM capacity (see Schmiedek et al, 2009 ; Jastrzebski et al, 2021 ), may be more sensitive to subtle improvements to the testing conditions resulting from tACS (e.g., improved attention focusing).…”