Fig. 6.

Specific delay in naturalistic flight sequence compared with the static delay response field. A: neuronal response of a facilitated unit to naturalistic flight sequences with linearly increasing pulse rates. Left panels show the PSTH (bin width = 2 ms), and right panels show the mean number of spikes per repetition for each pulse/echo pair. Top row shows the response to the sequence where both targets were presented together; middle and bottom rows show the responses of sequences where only target 1 or target 2 was presented, respectively. The acoustic stimulation in each sequence is preceded by a 50-ms silent period to determine the level of spontaneous activity and is followed by another 200-ms silent period. An asterisk marks the pulse/echo pair evoking the highest spike rate for the sequences with only target 1 or target 2. The specific delays are indicated at each maximum response position. B: the DRF for the same unit as shown in A. The asterisk marks BD, and the circle marks CD. Note that the BD of 7.0 ms is significantly longer than the specific delays in the naturalistic flight sequence.