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Longitudinal neurostimulation in older adults improves working memory.

Jones KT, Stephens JA, Alam M, Bikson M, Berryhill ME - PLoS ONE (2015)

Bottom Line: Such regimens generally result in temporary WM benefits to the trained tasks but minimal transfer of benefit to untrained tasks.The results demonstrated that all groups benefited from WM training, as expected.These results demonstrate that tDCS-linked WM training can provide long-term benefits in maintaining cognitive training benefits and extending them to untrained tasks.

View Article: PubMed Central - PubMed

Affiliation: Memory and Brain Laboratory, Department of Psychology, University of Nevada, Reno, Nevada, United States of America; Cognitive Neuropsychology Lab, Department of Neurology, Georgetown University Medical Center, Washington, District of Columbia, United States of America.

ABSTRACT
An increasing concern affecting a growing aging population is working memory (WM) decline. Consequently, there is great interest in improving or stabilizing WM, which drives expanded use of brain training exercises. Such regimens generally result in temporary WM benefits to the trained tasks but minimal transfer of benefit to untrained tasks. Pairing training with neurostimulation may stabilize or improve WM performance by enhancing plasticity and strengthening WM-related cortical networks. We tested this possibility in healthy older adults. Participants received 10 sessions of sham (control) or active (anodal, 1.5 mA) tDCS to the right prefrontal, parietal, or prefrontal/parietal (alternating) cortices. After ten minutes of sham or active tDCS, participants performed verbal and visual WM training tasks. On the first, tenth, and follow-up sessions, participants performed transfer WM tasks including the spatial 2-back, Stroop, and digit span tasks. The results demonstrated that all groups benefited from WM training, as expected. However, at follow-up 1-month after training ended, only the participants in the active tDCS groups maintained significant improvement. Importantly, this pattern was observed for both trained and transfer tasks. These results demonstrate that tDCS-linked WM training can provide long-term benefits in maintaining cognitive training benefits and extending them to untrained tasks.

No MeSH data available.


TDCS Current modeling.Modeling of current flow when applying 1.5 mA tDCS for F4 anodal (top) and P4 anodal (bottom) stimulation and the cathodal electrode placed on the contralateral cheek. The top row for each montage shows the electrical field (EF) magnitude plots. The bottom row for each montage is the radial EF plots showing the direction of stimulation. The red shows inward (anodal) EF, while blue represents outward (cathodal) EF.
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pone.0121904.g002: TDCS Current modeling.Modeling of current flow when applying 1.5 mA tDCS for F4 anodal (top) and P4 anodal (bottom) stimulation and the cathodal electrode placed on the contralateral cheek. The top row for each montage shows the electrical field (EF) magnitude plots. The bottom row for each montage is the radial EF plots showing the direction of stimulation. The red shows inward (anodal) EF, while blue represents outward (cathodal) EF.

Mentions: We modeled current flow to more precisely identify the spatial extent of brain stimulation after anodal tDCS to PFC and PPC sites; see Fig 2. This analysis confirmed that tDCS to the PFC supplied current to PFC regions, but current also reached orbitofrontal and ventral temporal regions. Similarly, the PPC site stimulated PPC as well as more posterior occipital and ventral temporal regions. To our surprise, there was considerable overlap of current flow, suggesting that regardless of stimulation site, current reached frontoparietal networks strongly activated during WM performance.


Longitudinal neurostimulation in older adults improves working memory.

Jones KT, Stephens JA, Alam M, Bikson M, Berryhill ME - PLoS ONE (2015)

TDCS Current modeling.Modeling of current flow when applying 1.5 mA tDCS for F4 anodal (top) and P4 anodal (bottom) stimulation and the cathodal electrode placed on the contralateral cheek. The top row for each montage shows the electrical field (EF) magnitude plots. The bottom row for each montage is the radial EF plots showing the direction of stimulation. The red shows inward (anodal) EF, while blue represents outward (cathodal) EF.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4388845&req=5

pone.0121904.g002: TDCS Current modeling.Modeling of current flow when applying 1.5 mA tDCS for F4 anodal (top) and P4 anodal (bottom) stimulation and the cathodal electrode placed on the contralateral cheek. The top row for each montage shows the electrical field (EF) magnitude plots. The bottom row for each montage is the radial EF plots showing the direction of stimulation. The red shows inward (anodal) EF, while blue represents outward (cathodal) EF.
Mentions: We modeled current flow to more precisely identify the spatial extent of brain stimulation after anodal tDCS to PFC and PPC sites; see Fig 2. This analysis confirmed that tDCS to the PFC supplied current to PFC regions, but current also reached orbitofrontal and ventral temporal regions. Similarly, the PPC site stimulated PPC as well as more posterior occipital and ventral temporal regions. To our surprise, there was considerable overlap of current flow, suggesting that regardless of stimulation site, current reached frontoparietal networks strongly activated during WM performance.

Bottom Line: Such regimens generally result in temporary WM benefits to the trained tasks but minimal transfer of benefit to untrained tasks.The results demonstrated that all groups benefited from WM training, as expected.These results demonstrate that tDCS-linked WM training can provide long-term benefits in maintaining cognitive training benefits and extending them to untrained tasks.

View Article: PubMed Central - PubMed

Affiliation: Memory and Brain Laboratory, Department of Psychology, University of Nevada, Reno, Nevada, United States of America; Cognitive Neuropsychology Lab, Department of Neurology, Georgetown University Medical Center, Washington, District of Columbia, United States of America.

ABSTRACT
An increasing concern affecting a growing aging population is working memory (WM) decline. Consequently, there is great interest in improving or stabilizing WM, which drives expanded use of brain training exercises. Such regimens generally result in temporary WM benefits to the trained tasks but minimal transfer of benefit to untrained tasks. Pairing training with neurostimulation may stabilize or improve WM performance by enhancing plasticity and strengthening WM-related cortical networks. We tested this possibility in healthy older adults. Participants received 10 sessions of sham (control) or active (anodal, 1.5 mA) tDCS to the right prefrontal, parietal, or prefrontal/parietal (alternating) cortices. After ten minutes of sham or active tDCS, participants performed verbal and visual WM training tasks. On the first, tenth, and follow-up sessions, participants performed transfer WM tasks including the spatial 2-back, Stroop, and digit span tasks. The results demonstrated that all groups benefited from WM training, as expected. However, at follow-up 1-month after training ended, only the participants in the active tDCS groups maintained significant improvement. Importantly, this pattern was observed for both trained and transfer tasks. These results demonstrate that tDCS-linked WM training can provide long-term benefits in maintaining cognitive training benefits and extending them to untrained tasks.

No MeSH data available.