Table 1. Summary of ensemble changes occurring under different experimental conditions.

		Responsive units		Statistics		Response type
Experimental condition (no. of moths; no. of units)	Total	At start	At end	Recruited	Lost	Excited	Inhibited
Forward-paired (4; 40)
Mean	10.0	5.0	8.0	3.8	0.5	7.8	0.2
SE	±2.7	±1.6	±1.6	±0.9	±0.6	±1.0	±0.2
Range	6-17
CS only (6; 52)
Mean	8.7	6.0	4.0	0.2	2.0	4.0	0
SE	±0.9	±0.6	±0.7	±0.2	±0.7	±0.8
Range	7-13
Differential conditioning (5; 69)
CS+
Mean	16.3	7.5	8.8	3.8	2.5	6.8	2.0
SE	±3.4	±1.4	±1.0	±1.0	±0.9	±0.7	±0.7
Range	12-25
CS-
Mean	16.3	9.8	7.8	0.8	2.8	6.2	1.6
SE	±3.4	±1.0	±1.0	±0.3	±0.5	±0.7	±0.6
Range	12-25
2-odor CS only (4; 73)
CS1
Mean	18.3	10.2	8.8	0.3	1.7	5.7	3.1
SE	±6.8	±6.1	±4.8	±0.1	±0.4	±3.3	±2.6
Range	11-34
CS2
Mean	18.3	9.8	7.8	0.5	2.5	5.3	2.5
SE	±6.8	±5.8	±4.5	±0.3	±0.6	±3.6	±2.3
Range	11-34

Summary statistics of recordings from 230 units in 18 moths. The first column lists the conditioning treatment (n, number of moths; number of units). All values in the following columns are the average number of units per ensemble in each of the four experimental categories. Total, the average number of units identified in each ensemble, the standard error, and the range of units across ensembles. Start, the average number of units that responded to the odor stimulus at the beginning of the experiment. End, the average number of units that responded to the odor stimulus at the end of the conditioning experiment. Recruited, the average number of neurons that were unresponsive at the start but began responding during or after conditioning treatment. Lost, the average number of units that initially responded but became statistically unresponsive. Response type, the type of response evoked by the presentation of the odor stimulus. Probabilities reported in the text result from Student's t tests between the indicated mean values.