Conflicting results in EEG alpha feedback studies

@article{Hardt1976ConflictingRI,
  title={Conflicting results in EEG alpha feedback studies},
  author={James V. Hardt and Joe Kamiya},
  journal={Biofeedback and Self-regulation},
  year={1976},
  volume={1},
  pages={63-75}
}
  • J. Hardt, J. Kamiya
  • Published 1 March 1976
  • Computer Science
  • Biofeedback and Self-regulation
Success or failure of EEG feedback training for alpha enhancement can depend on how alpha activity is quantified and fed back. Alpha-enhancement failures usually employ a percent time(%) technique; successes typically use amplitude integration(ε). To dramatize the differences between percent and integration techniques, we derived both measures simultaneously from left occipital(O1) and left central(C3) sites for 16 male subjects who were given 5.6 hours of integrated alpha feedback from the… 
Neurofeedback learning modifies the incidence rate of alpha spindles, but not their duration and amplitude
TLDR
It is proposed that future research on alpha-neurofeedback should explore reinforcement schedules based on detection of onsets and offsets of alpha waves, and employ these statistics for exploration and quantification of neurofeedback induced effects.
Alpha Neurofeedback Has a Positive Effect for Participants Who Are Unable to Sustain Their Alpha Activity
TLDR
This work uses an experimental paradigm in which an invalid feedback is given on a fraction of trials, such that both valid and invalid conditions can be obtained from the same participant, and shows that even under most stringent control, valid neurofeedback can help participants who are otherwise unable to sustain their alpha activity.
Long-term eyes-closed alpha-enhancement training: effects on alpha amplitudes and on experiential state.
TLDR
Even long-term alpha-enhancement training does not result in the learned enhancement of alpha strength significantly above optimal eyes-closed baseline levels and sub-baseline increases in alpha production during alpha training are most often the result of the gradual dissipation or neutralization of alpha-inhibitory influences.
Alpha enhancement the effect of feedback modality in an EEG biofeedback paradigm
Reviews of the EEC biofeedback literature indicate no substantive rationale for restriction of feedback modality to only auditory and visual feedback channels. Reports for other response systems
Alpha Neurofeedback Training for Performance Enhancement: Reviewing the Methodology
ABSTRACT Introduction. Considerable interest has been, and still is, generated by the potential performance enhancing benefits of alpha neurofeedback training (NFT) for healthy participants. A
Interpreting EEG alpha activity
Control of Alpha Rhythm (8–13 Hz) Using Neurofeedback
TLDR
Various aspects of this controversy regarding the enhancement of alpha power are discussed and some issues with past approaches of neurofeedback driven alpha enhancement are highlighted.
Methodological issues in alpha biofeedback training
TLDR
It is believed that the probabilities of successful feedback enhancement of alpha can be substantially improved by incorporating the following suggestions: (a) employing at least four training sessions, and (b) the use of continuous rather than dichotomous feedback, supplemented by periodic quantitative scores of progress.
Low-resolution electromagnetic tomography neurofeedback
TLDR
A method for extracting and feeding back intracranial current density is established and an experimental study is carried out to ascertain the ability of the participants to drive their own EEG power in a desired direction, the first application of an EEG inverse solution to neurofeedback.
...
...

References

SHOWING 1-10 OF 15 REFERENCES
ALPHA CONDITIONING: A CONTROLLED STUDY
TLDR
It was found that subjects who received contingent feedback produced significantly more alpha than did yoked and nonreinforced controls, and subjects acquired the alpha-producing response rapidly, reaching 80 per cent of asymptotic performance in 20 minutes.
Spectral analysis of the EEG in meditation.
  • J. Banquet
  • Psychology
    Electroencephalography and clinical neurophysiology
  • 1973
Alpha control: Effectiveness of two kinds of feedback
Eleven volunteer Ss participated on 2 separate days in an alpha control study. On Day 1, an auditory feedback tone was on during the presence of alpha and S was instructed to turn alpha on or off
Hypnotic Susceptibility increased by EEG Alpha Training
MORE than a decade of research on hypnotic susceptibility and its correlates has demonstrated repeatedly the stability of the phenomenon, its independence from standard tests of suggestibility and of
Interactive effects of alpha feedback and instructional set on subjective state.
TLDR
The results showed that for an “alpha experience” to occur, both alpha activity and alpha set are necessary; neither alone is sufficient.
Parameters of eyes-closed alpha enhancement.
TLDR
It was found that increases in emitted occipital alpha under eyes-closed conditions are related to contingent reinforcement and Proportional feedback was most efficient in the rapid development of eyes- closed training.
Visual Effects on Alpha Feedback Training
Presenting an audible indication of subjects' electroencephalographic alpha activity under conditions of dim ambient illumination led to systematic increases in alpha density, while in total darkness
Recognition of aspects of consciousness through association with EEG alpha activity represented by a light signal.
TLDR
Greatest achievement of enhanced alpha activity appeared to be related to narrowing of perceptual awareness and pleasant feeling states.
Personality Variables and Alpha Enhancement: A Correlative Study
Investigations into possible relationships between EEG and personality traits began in 1935 (Lemere, 1935), and have continued sporadically (Saul et al., 1937; Gottlober, 1938; Lindsley, 1938; Henry
...
...