Brain training is topical yet controversial. Effects are often limited to trained tasks; and near and far effects to untrained tasks or everyday life measures are often small or lacking altogether. More recent approaches use evidence from cognitive neuroscience on neuroplasticity, resulting in novel cognitive interventions. This special issue encompasses the state of the art of these interventions. Two systematic reviews and nine experimental studies in a variety of patient groups or healthy participants are included, the results of which mostly confirm earlier findings: effects on trained tasks are consistently reported, but generalisation in terms of functional outcome is limited and little evidence is found of long-term effects. In general, the studies show promising, yet challenging training effects on cognition in healthy persons and patients with cognitive deficits. As such, they may be seen as positive "proof of principle" studies, highlighting that cognitive enhancement is possible. The field of brain training, however, is in urgent need of larger and more thoroughly designed studies. These future studies should also include outcome measures on daily functioning, self-efficacy and quality of life in addition to neuropsychological tests or tasks related to cognitive functioning.
Keywords: Cognitive rehabilitation; brain injury; mild cognitive impairment; outcome; working-memory training.