Fig. 2. Stimulating FC2 neurons in a contiguous subset of fan-shaped body columns induces flies to orient along defined goal angles.
a, Simultaneous imaging and focal stimulation of FC2 neurons. b, Stimulation protocol. Images show average z-projection of raw fluorescence signal during the stimulation period from a single trial. Red squares mark the two locations of two-photon (2p) stimulation in the fan-shaped body (referred to as stim. A and stim. B). a.u., arbitrary units. Scale bar (middle left), 30 µm. c, Example FC2 ΔF/F0 signal and behavioural traces during a CsChrimson experiment. Left, FC2 activity over time. The red heat map shows the fraction of pixels of each column’s region of interest (ROI) that is inside the stimulation (stim.) ROI. Right, heading direction of a fly over time. Shaded blue and orange areas indicate the stimulation period. Bottom, probability distribution of the fly’s heading direction across all trials for each stimulation location. d, Same as c but for a control fly that did not express CsChrimson. e, Probability distributions of heading direction for 10 (out of the 16 total) CsChrimson-expressing flies (left) and 10 (out of 10) control flies that did not express CsChrimson (right). The heading direction was zeroed by subtracting the fly’s mean heading direction across all stim. A trials. f, Mean probability distributions for all flies. g, Difference between mean heading direction during stim. A and stim. B trials for each fly (black dots). Mean ± s.e.m. across flies is indicated. Dashed red line indicates the expected difference in heading direction based on the mean difference in the stimulation location for each group (see Extended Data Fig. 4e). V-test for CsChrimson flies: μ = −173.4° (left dashed line), P = 1.49 × 10−3. V-test for no CsChrimon flies: μ = −164.9° (right dashed line), P = 0.93.