Table 3.

Means (standard deviation) of cognitive scores by sleep duration

Sleep Duration	Animal Naming	Block Design	Symbol Digit	Word List
4 hours (or less)	50.65 (10.29)	45.78 (13.35)	50.95 (16.04)	51.36 (11.36)
5 hours	51.77 (11.25)	47.90 (11.90)	52.89 (12.80)	52.67 (10.39)
6 hours	53.03 (10.89)	50.90 (13.23)	54.03 (13.09)	52.03 (10.69)
7 hours	53.60 (10.52)	52.24 (14.68)	54.79 (11.76)	51.81 (10.27)
8 hours	52.93 (10.41)	51.20 (12.61)	52.65 (11.38)	51.34 (10.37)
9 hours	51.58 (10.52)	48.38 (12.89)	48.45 (12.29)	49.93 (10.68)
10 hours (or more)	49.82 (10.51)	45.57 (12.88)	46.16 (13.92)	50.24 (13.52)