Table 1.

Observed Descriptive Statistics and Correlations between Average Classical Conditioning, First Interval Response, Second Interval Response, and Third Interval Response within Each Age (First Half) and between Ages (Second Half)

	Age 3 (N = 200)				Age 4 (N = 195)				Age 5 (N = 190)				Age 6 (N =184)				Age 8 (N = 172)
	Ave.	FIR	SIR	TIR	Ave.	FIR	SIR	TIR	Ave.	FIR	SIR	TIR	Ave.	FIR	SIR	TIR	Ave.	FIR	SIR	TIR
Mean	.067	.073	.060	.067	.057	.034	.060	.076	.069	.073	.080	.053	.096	.105	.085	.099	.100	.101	.088	.112
SD	.071	.106	.097	.096	.059	.071	.080	.107	.068	.112	.102	.083	.081	.111	.132	.106	.075	.122	.099	.128
FIR	.675**	1	.273**	.110	.805**	1	.336**	.556**	.699**	1	.221**	.101	.705**	1	.229**	.319**	.664**	1	.273**	.018
SIR	.787**		1	.460**	.647**		1	.292**	.739**		1	.273**	.733**		1	.240**	.677**		1	.130
TIR	.700**			1	.853**			1	.600**			1	.697**			1	.616**			1
Age 4
Ave.	.095
FIR		.123
SIR			−.040
TIR	.			.076
Age 5
Ave.	.211**				.142*
FIR		.077				.046
SIR			.126				−.023
TIR				.064				.093
Age 6
Ave.	.080				.121				.035
FIR		.144*				.031				.170*
SIR			−.040				.033				−.100
TIR				.086				.101				−.070
Age 8
Ave.	.126				.076				.091				.360**
FIR		−.006				−.040				.061				.148*
SIR			.079				.015				.119				.185*
TIR				−.052				.056				.008				.099

Note. Ave. = Average classical conditioning; FIR = First interval response, SIR = Second interval response, TIR = Third interval response.

^*p < .05

^**p < .01.