Growing evidence supports the idea that the ultimate
biofeedback is to reward sensory pleasure (e.g., enhanced visual clarity) in real-time to neural circuits that are associated with a desired performance, such as excellent memory retrieval.
Neurofeedback is
biofeedback that uses real-time sensory reward to brain activity associated with a certain performance (e.g., accurate and fast recall). Working memory is a key component of human intelligence. The challenges are in our current limited understanding of neurocognitive dysfunctions as well as in technical difficulties for closed-loop feedback in true real-time. Here we review recent advancements of real time
neurofeedback to improve
memory training in healthy young and older adults. With new advancements in neuromarkers of specific neurophysiological functions,
neurofeedback training should be better targeted beyond a single frequency approach to include frequency interactions and event-related potentials. Our review confirms the positive trend that
neurofeedback training mostly works to improve memory and cognition to some extent in most studies. Yet, the training typically takes multiple weeks with 2-3 sessions per week. We review various
neurofeedback reward strategies and outcome measures. A well-known issue in such training is that some people simply do not respond to
neurofeedback. Thus, we also review the literature of individual differences in psychological factors e.g., placebo effects and so-called "
BCI illiteracy" (
Brain Computer Interface illiteracy). We recommend the use of Neural modulation sensitivity or
BCI insensitivity in the
neurofeedback literature. Future directions include much needed research in
mild cognitive impairment, in non-Alzheimer's
dementia populations, and
neurofeedback using EEG features during resting and sleep for memory enhancement and as sensitive outcome measures.