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Temporal codes in the form of relative spike latency can efficiently encode sensory features.The implementation of such coding strategy requires a broad dynamic range of spike latencies in order to achieve sufficient coding capacity and resolution.The generation of spike latency codes in the sensory pathway remains largely unknown.We report that in individual auditory cortical neurons, spike latency codes for sound frequency cannot be simply attributed to thalamocortical relays, but are primarily generated de novo by local circuits, which fine-tune the integration time for spike generation after the arrival of thalamocortial inputs.Sharply tuned recurrent excitation shortens integration time selectively at the optimal frequency, while broadly tuned inhibition prolongs it preferentially at off-optimal frequencies.These push-and-pull antagonistic modulations greatly sharpen spike latency tuning and expand its dynamic range.Thus, thalamocortical circuit-like elementary synaptic circuits can convert information spatially coded in distributions of synaptic strength into temporal codes.