Memory signals from the thalamus: Early thalamocortical phase synchronization entrains gamma oscillations during long-term memory retrieval

► Intrathalamic and scalp EEG recorded in an epilepsy patient during memory retrieval. ► Enhanced beta synchrony between mediodorsal thalamic and frontal scalp electrodes. ► Granger causal influence of mediodorsal thalamic on frontal scalp EEG signal. ► Thalamic beta phase modulated frontal gamma oscillations (cross-frequency coupling). ► Beta-to-gamma coupling effect validated on group level (22 healthy participants).