Details

Autor(en) / Beteiligte

• Züst, Marc Alain
• Ruch, Simon
• Wiest, Roland
• Henke, Katharina

Titel

Implicit Vocabulary Learning during Sleep Is Bound to Slow-Wave Peaks

Ist Teil von

• Current biology, 2019-02, Vol.29 (4), p.541-553.e7

Ort / Verlag

England: Elsevier Ltd

Erscheinungsjahr

2019

Quelle

ScienceDirect

Beschreibungen/Notizen

• Learning while asleep is a dream of mankind, but is often deemed impossible because sleep lacks the conscious awareness and neurochemical milieu thought to be necessary for learning. Current evidence for sleep learning in humans is inconclusive. To explore conditions under which verbal learning might occur, we hypothesized that peaks of slow waves would be conducive to verbal learning because the peaks define periods of neural excitability. While in slow-wave sleep during a nap, a series of word pairs comprising pseudowords, e.g., “tofer,” and actual German words, e.g., “Haus” (house), were played to young German-speaking women and men. When the presentation of the second word of a pair (e.g., “Haus” of “tofer-house”) coincided with an ongoing slow-wave peak, the chances increased that a new semantic association between the pair had been formed and retained. Sleep-formed associations translated into awake ones, where they guided forced choices on an implicit memory test. Reactivations of sleep-formed associations were mirrored by brain activation increases measured with fMRI in cortical language areas and the hippocampus, a brain structure critical for relational binding. We infer that implicit relational binding had occurred during peaks of slow oscillations, recruiting a hippocampal-neocortical network comparable to vocabulary learning in the waking state. •Humans can encode verbal associative information (word pairs) during slow-wave sleep•Memory was best for pairs that were encoded in sync with ongoing slow-wave peaks•Slow-wave sleep appears to entail windows of opportunity for synaptic potentiation•The hippocampus mediated retrieval, suggesting episodic memory formation during sleep Züst et al. show that, during sleep, slow-wave peaks serve as windows of opportunity for encoding of verbal information. Memory for sleep-encoded information is best if information is repeatedly presented in sync with peaks. Hippocampus activates with successful retrieval, indicating sleep encoding is accomplished using episodic memory functions.