This lecture provides an overview of hippocampus synaptic plasticity, network oscillations, and neuromodulation. It explains the different forms of synaptic potentiation and depression, such as long-term potentiation and depression, and spike timing-dependent potentiation and depression. The hippocampus displays oscillations similar to those in the cortex, contributing to cognitive functions like learning and memory. The role of neuromodulators like Histamine, Acetylcholine, Noradrenaline, Dopamine, and Acetone in gating synaptic plasticity and enhancing network-level oscillations for higher-order cognitive processing is also discussed.