Induced neural phase precession through exogenous electric fields is a causal mechanism linking local field potential (LFP) dynamics to phase precession, a phenomenon where the timing of neural spiking shifts relative to LFPs. This study demonstrates that alternating current (AC) stimulation can induce phase precession in both humans and non-human primates (NHPs), with implications for synaptic plasticity and neuroplasticity. In three experiments, AC stimulation was applied to modulate LFPs in humans, NHPs, and computational models. In humans, continuous stimulation of motor cortex oscillations led to a -90° phase shift in maximal corticospinal excitability. In NHPs, AC stimulation induced phase precession in a subset of entrained neurons (≈30%). Multiscale modeling suggests that phase precession is driven by NMDA-mediated synaptic plasticity. These findings provide mechanistic and causal evidence that phase precession is a global neocortical process, crucial for synaptic plasticity and learning. AC-induced phase precession and subsequent synaptic plasticity could be key for developing novel therapeutic neuromodulation methods. The study also shows that AC stimulation can modulate neural spiking activity in NHPs, with phase shifts observed in both alpha and beta frequencies. Computational modeling further supports that phase precession is linked to synaptic plasticity, with changes in synaptic weights mirroring AC-induced phase shifts. The results suggest that phase precession is a network-level process, reflecting local connectivity and plasticity. The study highlights the potential of AC stimulation for therapeutic applications in neurological and psychiatric disorders.Induced neural phase precession through exogenous electric fields is a causal mechanism linking local field potential (LFP) dynamics to phase precession, a phenomenon where the timing of neural spiking shifts relative to LFPs. This study demonstrates that alternating current (AC) stimulation can induce phase precession in both humans and non-human primates (NHPs), with implications for synaptic plasticity and neuroplasticity. In three experiments, AC stimulation was applied to modulate LFPs in humans, NHPs, and computational models. In humans, continuous stimulation of motor cortex oscillations led to a -90° phase shift in maximal corticospinal excitability. In NHPs, AC stimulation induced phase precession in a subset of entrained neurons (≈30%). Multiscale modeling suggests that phase precession is driven by NMDA-mediated synaptic plasticity. These findings provide mechanistic and causal evidence that phase precession is a global neocortical process, crucial for synaptic plasticity and learning. AC-induced phase precession and subsequent synaptic plasticity could be key for developing novel therapeutic neuromodulation methods. The study also shows that AC stimulation can modulate neural spiking activity in NHPs, with phase shifts observed in both alpha and beta frequencies. Computational modeling further supports that phase precession is linked to synaptic plasticity, with changes in synaptic weights mirroring AC-induced phase shifts. The results suggest that phase precession is a network-level process, reflecting local connectivity and plasticity. The study highlights the potential of AC stimulation for therapeutic applications in neurological and psychiatric disorders.