Fig 1.
The Consolidated Standards of Reporting Trials (CONSORT) flow diagram for transcranial direct current stimulation (tDCS) clinical trial.
Table 1.
Demographics, sleep quality and neurocognitive characteristics across the randomized groups.
Table 2.
Comparations of sleep components in mild NCD-AD with statuses of subjective sleep quality (score changes).
Fig 2.
Comparisons of the treatment-induced changes of ADAS-Cog across follow-up observations.
The poor sleepers had more cognitive gains than the good sleeps. Box plot represents the differences of ADAS-Cog score changes across time points. Abbreviations: tDCS = Transcranial direct current stimulation; WMT = Working memory training; CCT = Controlled cognitive training; ADAS-Cog = The Alzheimer’s Disease Assessment Scale–Cognitive Subscale.
Fig 3.
Comparisons of the treatment-induced changes of domain-specific cognitive functions, including (a) memory (b) language (c) praxis, and (d) orientation.
In the individuals received tDCS-CCT treatment, the poor sleepers had more memory enhancement than the good sleeps. Blue line represents the good sleeper; red line represents poor sleeper. Abbreviations: tDCS = Transcranial direct current stimulation; WMT = Working memory training; CCT = Controlled cognitive training. Error bars represent the standard error (SEM). * Indicates significant between-group difference (p < 0.05).
Fig 4.
Correlation matrix for the changes in sleep quality and global cognitive function.
The colour scale depicts the strength of the Pearson correlation coefficient. Superimposed text represents the actual numerical value of the Pearson correlation coefficient. The asterisk depicts the statistical significance of the correlation: * represents p < 0.05, ** represents p < 0.005. Abbreviations: tDCS = Transcranial direct current stimulation; WMT = Working memory training; CCT = Controlled cognitive training; PSQI = Pittsburgh Sleep Quality Index; SC = Score change; ADAS-Cog = The Alzheimer’s Disease Assessment Scale–Cognitive Subscale.