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Scientific Reports Feb 2024The rise in the global population of older adults underscores the significance to investigate age-related cognitive disorders and develop early treatment modalities....
The rise in the global population of older adults underscores the significance to investigate age-related cognitive disorders and develop early treatment modalities. Previous research suggests that non-invasive transcranial Alternating Current Stimulation (tACS) can moderately improve cognitive decline in older adults. However, non-declarative cognition has received relatively less attention. This study investigates whether repeated (16-day) bilateral theta-gamma cross-frequency tACS targeting the Dorsolateral Prefrontal Cortex (DLPFC) enhances non-declarative memory. Computerized cognitive training was applied alongside stimulation to control for the state-of-the-brain. The Alternating Serial Reaction Time (ASRT) task was employed to assess non-declarative functions such as visuomotor skill and probabilistic sequence learning. Results from 35 participants aged 55-82 indicated that active tACS led to more substantial improvements in visuomotor skills immediately after treatment, which persisted 3 months later, compared to sham tACS. Treatment benefit was more pronounced in older adults of younger age and those with pre-existing cognitive decline. However, neither intervention group exhibited modulation of probabilistic sequence learning. These results suggest that repeated theta-gamma tACS can selectively improve distinct non-declarative cognitive aspects when targeting the DLPFC. Our findings highlight the therapeutic potential of tACS in addressing deficits in learning and retaining general skills, which could have a positive impact on the quality of life for cognitively impaired older individuals by preserving independence in daily activities.
Topics: Humans; Aged; Transcranial Direct Current Stimulation; Quality of Life; Learning; Cognition; Brain
PubMed: 38418511
DOI: 10.1038/s41598-024-55125-2 -
Operative Neurosurgery (Hagerstown, Md.) Feb 2024
Topics: Humans; Pulvinar; Thalamus; Neurosurgical Procedures
PubMed: 37820265
DOI: 10.1227/ons.0000000000000935 -
Journal of Affective Disorders Jun 2024Transcranial magnetic stimulation (TMS) is an evidence-based approach to treatment- resistant Major Depressive Disorder (TRD). Sleep dysfunction is associated with poor...
BACKGROUND
Transcranial magnetic stimulation (TMS) is an evidence-based approach to treatment- resistant Major Depressive Disorder (TRD). Sleep dysfunction is associated with poor outcomes in TRD, however, the impacts of sleep dysfunction on TMS treatment has yet to be defined. This study examined the association between sleep dysfunction and improvement in depression symptoms with TMS treatment for TRD.
METHODS
A retrospective observational cohort study was conducted examining all Veterans receiving TMS treatments through the "VA TMS Clinical Pilot Program" over a three-year period. The Patient Health Questionnaire (PHQ-9) sleep item was utilized to assess sleep dysfunction. The association between sleep dysfunction improvements during TMS treatment with depression outcomes was analyzed.
RESULTS
94.3 % (N = 778) of Veterans reported baseline sleep dysfunction. Chi-square analysis demonstrated higher rates of depression remission at the completion of TMS treatment for those with sleep improvement at weeks 1, 3 and 6 (all p < .001). ANOVA comparing sleep improvements and end of treatment PHQ-8 score (modified to remove sleep item) found a statistically significant difference in mean improvements of depression scores at all 3 time points.
LIMITATIONS
Limitations include those that are inherent to retrospective studies, as well as limitations in using the PHQ-9 sleep item as the primary means to assess sleep dysfunction.
CONCLUSION
This study reports on the largest sample size to date examining the relationship between sleep dysfunction and TMS treatment outcomes for MDD, and found that improvement in sleep dysfunction was associated with greater reductions in end of treatment depression symptoms including higher depression remission rates.
PubMed: 38944289
DOI: 10.1016/j.jad.2024.06.077