The current results support the involvement of the human thalamus in sleep spindle-related neural activity. Sleep spindles were found in the ANT and in the MD and ripples coupled with sleep spindles resulted in distinguishable spectro-temporal differences in the thalamus but not at the scalp. The major finding is that ripples are also present in the thalamus, which seems to contribute to intellectual ability through a tight interaction between spindles and ripples. Limitations of the study are the lack of direct testing of offline memory processes during sleep. Also, the sample size is too low to reveal the specific IQ subscores which are influenced by the coordinated activity of sleep spindles and ripples in the thalamus. Co-registration from the hippocampus, thalamus and scalp will present an opportunity to reveal the hippocampal-thalamo-cortical pathway in further research, providing target circuits for neuromodulation and therapeutics. Furthermore, our participants suffered from medically refractory epilepsy being subjects of poly-antiseizure medication treatment. This type of treatment was shown to reduce sleep slow wave (0.1-2 Hz) EEG amplitude, increase sleep spindle frequency (11-16 Hz) power, and decrease slow wave-sleep spindle cross-frequency coupling in epilepsy patients (Roebber et al. 2022). As our present investigation focuses on sleep spindle-related activity of epilepsy patients we cannot entirely exclude the possibility that our reported findings are indeed partially influenced by antiseizure medications. Further investigations focusing on the thalamic recordings of patients groups with different medication are needed in order to provide unequivocal evidence for the claims we made in our paper.