1a. You see a dip in a spike-triggered average about 50 ms before the spike time, a peak close to the spike time, and zero after the spike time. Explain what this can mean. 1b. You see a peak in a spike-triggered average near the spike time that lasts for 20 ms after the spike time. Explain what this can mean. 1a. You see a dip in a spike-triggered average about 50 ms before the spike time, a peak close to the spike time, and zero after the spike time. Explain what this can mean. 1b. You see a peak in a spike-triggered average near the spike time that lasts for 20 ms after the spike time. Explain what this can mean