Figure 4.

Spaced Training Induces Region-Specific Plasticity of γ3,γ3β′1-MBON Responses

(A–F) Measuring odor responses in γ3,γ3β′1-MBONs. (A and B) Imaging plane for the β′1 region of γ3β′1 MBON dendritic field and training and imaging protocol. (A) Spaced training significantly reduced CS− responses in β′1, but not with (B) the reversed protocol where CS− precedes CS+ in each trial. (C and D). Imaging plane for the γ3 region of the γ3,γ3β′1-MBON dendritic fields and training and imaging protocols. (C) Spaced training significantly reduced CS+ responses in γ3. (D) The reversed protocol also reduced responses to CS+ in γ3. (E and F) Imaging plane in presynaptic terminals of γ3,γ3β′1-MBONs and training and imaging protocols. Neither spaced training (E) or reversed spaced training (F) significantly altered odor-evoked responses in the γ3,γ3β′1 presynaptic terminals. CS+ data correspond to average of experiments in which 50% of trials used MCH as CS+ and 50% used OCT as CS+. Same applies for CS− data. Odor-evoked activity traces show means (solid line) with SEM (shadow). A black line underneath indicates a 5 s odor. Bar graphs display normalized area under the curve as means ± SEM. Individual data points are displayed as dots, and paired measurements are connected by stippled lines. Asterisks denote a significant difference between averaged responses to CS+ and CS−. See Figure S4 for non-normalized traces for the CS+, CS−, and third odor and Table S1 for statistics.