Potential Role of Synaptic Activity to Inhibit LTD Induction in Rat Visual Cortex

Figure 4

Examples of unfiltered and band-pass filtered (0.1–5 Hz) ECoG activity recorded in V1 of urethane-anesthetized rats. (a) Baseline (prestimulation) ECoG activity showed large, slow oscillations at very low frequencies (<1 Hz) and periods of electrical quiescence. (b) Application of LFS to the LGN resulted in the appearance of more regular, continuous activity between 0.6 and 2 Hz. (c) RF stimulation alone or (d) paired LFS + RF stimulation resulted in a further increase in the frequency and amplitude of cortical activity. (e) Rats treated with a combination of scopolamine and mecamylamine (scopol., 10 mg/kg + mecamyl., 5 mg/kg) continued to exhibit a more complex, rhythmic activity during LFS + RF stimulation (calibration bars are 0.5 mV and 1 s).