Supplementary Figure 4: Decoding value from spikes and LFPs

Since both spiking and LFP decoders identified reward types unreliably, we focused on decoding only value information. (a) LDA classified 8 pictures into 4 value categories, based on single unit spiking, LFP or both. Peak accuracy was approximately 44% with the spike decoder and 35% with the LFP decoder (chance = 25%). Decoding based on single neurons was more accurate than LFPs, and adding LFPs to single units did not significantly improve accuracy. Each line shows mean accuracy ±SEM across 44 behavioral sessions for both subjects. (b) Scatter plots of peak accuracy from spike or LFP decoding as shown in A for each recording session. Decoding accuracy improves with more simultaneously recorded signals. (c) LDAs classified pictures into value categories as described in A, with decoding based on analytic amplitudes of individual LFP bands. Theta (4-8 Hz) and high gamma (70-200 Hz) provided the best value decoding in both subjects; however a small amount of information was also contained in other frequency bands.