Theta-gamma coupling increases during the learning of item-context associations. This study investigates the role of theta-gamma coupling in hippocampal memory processing. Rats learned to associate items with their spatial context, and theta-gamma coupling in the CA3 region of the hippocampus increased as learning progressed. The strength of theta-gamma coupling was directly correlated with performance accuracy during learning. These findings suggest that theta-gamma coupling plays a functional role in memory recall. Theta-gamma coupling refers to the phase-amplitude cross-frequency coupling between theta (4–12 Hz) and gamma (30–100 Hz) oscillations in the hippocampus. This coupling is thought to support a neural code for memory processing. The study found that during context exploration, theta-phase modulation of the low gamma (LG) subband (30–60 Hz) in CA3 increased with learning. The strength of theta-gamma coupling was strongly correlated with performance accuracy, indicating that this coupling is involved in memory recall. The study also found that theta-gamma coupling remained high during overtraining sessions, suggesting that the coupling persists as long as task performance is high. The increase in theta-gamma coupling during learning could not be explained by changes in theta power, running speed, or gamma power. These findings support the view that theta-gamma coupling contributes to memory processing and that the hippocampus plays a key role in associative memory. The study provides empirical evidence that theta-gamma coupling in the hippocampus supports cognitive functions, specifically memory processing. The findings are consistent with theoretical models that suggest theta-gamma coupling is involved in information coding relevant to successful recall. The results also indicate that theta-gamma coupling may be more functionally important than either of the individual rhythms alone. The study highlights the importance of theta-gamma coupling in memory processing and provides insights into the neural mechanisms underlying associative memory.Theta-gamma coupling increases during the learning of item-context associations. This study investigates the role of theta-gamma coupling in hippocampal memory processing. Rats learned to associate items with their spatial context, and theta-gamma coupling in the CA3 region of the hippocampus increased as learning progressed. The strength of theta-gamma coupling was directly correlated with performance accuracy during learning. These findings suggest that theta-gamma coupling plays a functional role in memory recall. Theta-gamma coupling refers to the phase-amplitude cross-frequency coupling between theta (4–12 Hz) and gamma (30–100 Hz) oscillations in the hippocampus. This coupling is thought to support a neural code for memory processing. The study found that during context exploration, theta-phase modulation of the low gamma (LG) subband (30–60 Hz) in CA3 increased with learning. The strength of theta-gamma coupling was strongly correlated with performance accuracy, indicating that this coupling is involved in memory recall. The study also found that theta-gamma coupling remained high during overtraining sessions, suggesting that the coupling persists as long as task performance is high. The increase in theta-gamma coupling during learning could not be explained by changes in theta power, running speed, or gamma power. These findings support the view that theta-gamma coupling contributes to memory processing and that the hippocampus plays a key role in associative memory. The study provides empirical evidence that theta-gamma coupling in the hippocampus supports cognitive functions, specifically memory processing. The findings are consistent with theoretical models that suggest theta-gamma coupling is involved in information coding relevant to successful recall. The results also indicate that theta-gamma coupling may be more functionally important than either of the individual rhythms alone. The study highlights the importance of theta-gamma coupling in memory processing and provides insights into the neural mechanisms underlying associative memory.