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Specific effects of EEG based neurofeedback training on memory functions in post-stroke victims.

Kober SE, Schweiger D, Witte M, Reichert JL, Grieshofer P, Neuper C, Wood G - J Neuroeng Rehabil (2015)

Bottom Line: NF training showed no effects on other cognitive functions than memory.Post-stroke victims with memory deficits could benefit from NF training as much as healthy controls.The used NF training protocols (SMR, Upper Alpha) had specific as well as unspecific effects on memory.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology, University of Graz, Universitaetsplatz 2/III, Graz, 8010, Austria. silvia.kober@uni-graz.at.

ABSTRACT

Background: Using EEG based neurofeedback (NF), the activity of the brain is modulated directly and, therefore, the cortical substrates of cognitive functions themselves. In the present study, we investigated the ability of stroke patients to control their own brain activity via NF and evaluated specific effects of different NF protocols on cognition, in particular recovery of memory.

Methods: N = 17 stroke patients received up to ten sessions of either SMR (N = 11, 12-15 Hz) or Upper Alpha (N = 6, e.g. 10-12 Hz) NF training. N = 7 stroke patients received treatment as usual as control condition. Furthermore, N = 40 healthy controls performed NF training as well. To evaluate the NF training outcome, a test battery assessing different cognitive functions was performed before and after NF training.

Results: About 70 % of both patients and controls achieved distinct gains in NF performance leading to improvements in verbal short- and long-term memory, independent of the used NF protocol. The SMR patient group showed specific improvements in visuo-spatial short-term memory performance, whereas the Upper Alpha patient group specifically improved their working memory performance. NF training effects were even stronger than effects of traditional cognitive training methods in stroke patients. NF training showed no effects on other cognitive functions than memory.

Conclusions: Post-stroke victims with memory deficits could benefit from NF training as much as healthy controls. The used NF training protocols (SMR, Upper Alpha) had specific as well as unspecific effects on memory. Hence, NF might offer an effective cognitive rehabilitation tool improving memory deficits of stroke survivors.

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Individual improvements and declines in cognitive performance after training, presented separately for stroke patients and healthy controls. Percentage of participants per group showing either increased (a) or decreased (b) performance in the different cognitive constructs (short-term STM, long-term LTM, and working memory WM) when comparing the pre- and post-assessment
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Fig4: Individual improvements and declines in cognitive performance after training, presented separately for stroke patients and healthy controls. Percentage of participants per group showing either increased (a) or decreased (b) performance in the different cognitive constructs (short-term STM, long-term LTM, and working memory WM) when comparing the pre- and post-assessment

Mentions: For each group, we determined the number of participants showing significantly increased, constant or decreased cognitive performance by counting the number of pre-post differences scores larger than the test specific critical differences and dividing this amount by the number of measurements per construct and participants [45, 46]. All groups showed the strongest performance improvements in memory tests (Fig. 4). Cognitive decline was present after training but never markedly over 20 % and therefore attributable to random performance fluctuations and not to any deleterious NF training effects (Fig. 4b) [45, 46]. Importantly, cognitive decline was comparable across groups. Statistical comparisons using chi-square tests revealed that the number of participants showing increased, constant or decreased cognitive performance was comparable between groups (all p-values > 0.10). SMR and UA NF training led to comparable individual improvements and decline in cognitive performance. The TAU group showed the lowest percentage of cognitive improvement in short- and long-term memory tasks compared to the NF training groups.Fig. 4


Specific effects of EEG based neurofeedback training on memory functions in post-stroke victims.

Kober SE, Schweiger D, Witte M, Reichert JL, Grieshofer P, Neuper C, Wood G - J Neuroeng Rehabil (2015)

Individual improvements and declines in cognitive performance after training, presented separately for stroke patients and healthy controls. Percentage of participants per group showing either increased (a) or decreased (b) performance in the different cognitive constructs (short-term STM, long-term LTM, and working memory WM) when comparing the pre- and post-assessment
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4666277&req=5

Fig4: Individual improvements and declines in cognitive performance after training, presented separately for stroke patients and healthy controls. Percentage of participants per group showing either increased (a) or decreased (b) performance in the different cognitive constructs (short-term STM, long-term LTM, and working memory WM) when comparing the pre- and post-assessment
Mentions: For each group, we determined the number of participants showing significantly increased, constant or decreased cognitive performance by counting the number of pre-post differences scores larger than the test specific critical differences and dividing this amount by the number of measurements per construct and participants [45, 46]. All groups showed the strongest performance improvements in memory tests (Fig. 4). Cognitive decline was present after training but never markedly over 20 % and therefore attributable to random performance fluctuations and not to any deleterious NF training effects (Fig. 4b) [45, 46]. Importantly, cognitive decline was comparable across groups. Statistical comparisons using chi-square tests revealed that the number of participants showing increased, constant or decreased cognitive performance was comparable between groups (all p-values > 0.10). SMR and UA NF training led to comparable individual improvements and decline in cognitive performance. The TAU group showed the lowest percentage of cognitive improvement in short- and long-term memory tasks compared to the NF training groups.Fig. 4

Bottom Line: NF training showed no effects on other cognitive functions than memory.Post-stroke victims with memory deficits could benefit from NF training as much as healthy controls.The used NF training protocols (SMR, Upper Alpha) had specific as well as unspecific effects on memory.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology, University of Graz, Universitaetsplatz 2/III, Graz, 8010, Austria. silvia.kober@uni-graz.at.

ABSTRACT

Background: Using EEG based neurofeedback (NF), the activity of the brain is modulated directly and, therefore, the cortical substrates of cognitive functions themselves. In the present study, we investigated the ability of stroke patients to control their own brain activity via NF and evaluated specific effects of different NF protocols on cognition, in particular recovery of memory.

Methods: N = 17 stroke patients received up to ten sessions of either SMR (N = 11, 12-15 Hz) or Upper Alpha (N = 6, e.g. 10-12 Hz) NF training. N = 7 stroke patients received treatment as usual as control condition. Furthermore, N = 40 healthy controls performed NF training as well. To evaluate the NF training outcome, a test battery assessing different cognitive functions was performed before and after NF training.

Results: About 70 % of both patients and controls achieved distinct gains in NF performance leading to improvements in verbal short- and long-term memory, independent of the used NF protocol. The SMR patient group showed specific improvements in visuo-spatial short-term memory performance, whereas the Upper Alpha patient group specifically improved their working memory performance. NF training effects were even stronger than effects of traditional cognitive training methods in stroke patients. NF training showed no effects on other cognitive functions than memory.

Conclusions: Post-stroke victims with memory deficits could benefit from NF training as much as healthy controls. The used NF training protocols (SMR, Upper Alpha) had specific as well as unspecific effects on memory. Hence, NF might offer an effective cognitive rehabilitation tool improving memory deficits of stroke survivors.

Show MeSH
Related in: MedlinePlus