Table 1. Correlations between sleep spindle parameters and intelligence in nap sleep recordings of 79 healthy young male subjects.

	Nap slow spindles						Nap fast spindles
	Density		Duration		Amplitude		Density		Duration		Amplitude
	r	p	r	p	r	p	r	p	r	p	r	p
F3	0.178	0.117	0.299*	0.007	−0.015	0.899	0.072	0.530	0.109	0.337	0.126	0.269
F4	0.169	0.137	0.312*	0.005	−0.030	0.794	0.033	0.774	0.112	0.326	0.098	0.390
C3	0.245	0.029	0.307*	0.006	−0.020	0.862	0.076	0.505	0.107	0.349	0.131	0.251
C4	0.234	0.038	0.286*	0.011	−0.045	0.694	0.036	0.754	0.139	0.223	0.105	0.355
O1	0.183	0.107	0.251*	0.026	−0.044	0.704	0.102	0.373	0.098	0.390	0.078	0.497
O2	0.241	0.032	0.294*	0.008	−0.072	0.531	0.164	0.149	0.090	0.430	0.039	0.736

Correlation coefficients which remain significant after correcting for multiple testing are marked by an asterisk.