a Peak power increase, frequency at peak, and firing rate of MUA across the set of responsive electrodes as a function of optogenetic stimulation frequency. A schematic representation of the stimulation and recording site is shown on the left. Error bands represent SEM. b Time-frequency representations of LFP data, recorded with the deepest electrode, during optical stimulation with 5 Hz (50% duty cycle rectangular blue light pulses—top; ten trials). The range of MMCE window sizes was matched with the range spanned by the SLT wavelets. c Scaled correlation analysis (SCA) on the data from b. Top: time-resolved. Bottom: time-collapsed around the temporal location of the burst in b. d Analysis of multi-unit activity (MUA) recorded on the same electrode as the LFP in b. Top: Peri-Stimulus Time Histogram (PSTH); bottom: binary SCA on the MUA spikes. e Time-frequency representations of LFP data recorded during stimulation with 65 Hz, on a more superficial electrode (single trial). Green numbers denote periods with peak power at 65 Hz (1 and 3) and with reduced power between these peaks (2). Red arrows indicate two high frequency (130 Hz) transients. f The single trial trace from e (top), followed by its band-passed versions (Butterworth IIR, order 3, bidirectional) at 60–70 Hz (middle) and 110–140 Hz (bottom). g SCA on the LFP signal from e and f, with time-collapsed versions at the locations of the two bursts indicated by red arrows in e. h Event-related potentials (ERP) aligned to light onset computed on the LFP signal during periods 1, 2, and 3, indicated in e. i The LFP signal between 30–80 ms, at the location of the high-frequency burst (first red arrow in e), in relation to the light stimulation profile.