Table 1.

Multiple regression statistics summary

	Spiking Parameters
	At threshold				At suprathreshold				LFP Parameters
	PSTH duration	Halftime	FSL	FSL jitter	Width	Halftime	FSL	FSL jitter	Peak magnitude	Peak time
10-kHz short tones
θ	33.3	34.6	37.4	35.0	27.1	36.1	45.4	51.5	73.5	25.8
n	119	119	119	119	113	113	113	113	119	95
R2	0.47	0.48	0.57	0.48	0.48	0.45	0.57	0.57	0.64	0.50
P	7.E-17	3.E-17	4.E-22	4.E-17	2.E-16	5.E-15	4.E-21	1.E-20	3.E-26	2.E-14
10-kHz long tones
θ	53.3	59.4	61.3	67.3	21.1	33.0	49.3	54.6	58.8	18.0
n	55	55	55	55	53	53	53	53	55	47
R2	0.43	0.43	0.32	0.27	0.44	0.49	0.39	0.12	0.62	0.54
P	5.E-07	5.E-07	4.E-05	3.E-04	5.E-07	4.E-08	4.E-06	4.E-02	1.E-11	3.E-08
20-kHz short tones
θ	30.0	36.5	37.3	44.2	32.6	30.6	30.4	42.2	42.5	24.6
n	99	99	99	99	93	93	93	93	99	85
R2	0.40	0.46	0.56	0.50	0.46	0.47	0.56	0.41	0.49	0.58
P	3.E-11	1.E-13	9.E-18	4.E-15	1.E-12	3.E-13	1.E-16	5.E-11	1.E-14	3.E-16
20-kHz long tones
θ	37.8	27.8	28.0	35.3	27.0	39.3	53.4	72.6	52.8	14.1
n	52	52	52	52	50	50	50	50	52	46
R2	0.39	0.38	0.38	0.29	0.36	0.39	0.48	0.28	0.31	0.64
P	7.E-06	8.E-06	9.E-06	2.E-04	3.E-05	9.E-06	3.E-07	4.E-04	1.E-04	4.E-10

Multiple regression was performed to determine the directionality of how each response parameter varied across the isofrequency lamina. The angle θ (in degrees) across the isofrequency lamina is the inverse tangent of the slope of the regression, where caudal to rostral would be 90° and medial to lateral would be 0°. Each regression was performed on the number of sites (n), with the descriptive statistics of a coefficient of determination (R²) and probability (P). PSTH, poststimulus time histogram; FSL, first spike latency; LFP, local field potential.