Table 2.

Mean (standard deviation) performance on shifting measures by age and condition. More negative rate residual scores indicate larger switch costs.

	Response times			Error rates			Rate residual scores
Global switch costs
Age	Pure	Mixed	RT cost	Pure	Mixed	Error cost	Global Cost
Young	487 (83)	1109 (257)	622 (214)	.03 (.03)	.04 (.04)	.01 (.03)	0.06 (0.80)
Old	732 (189)	1715 (652)	983 (546)	.02 (.02)	.04 (.06)	.03 (.06)	−0.10 (0.93)
Local switch costs
Age	Repeat	Switch	RT cost	Repeat	Switch	Error cost	Local Cost
Young	717 (154)	800 (161)	82 (94)	.04 (.04)	.05 (.05)	.01 (.05)	0.01 (0.62)
N-2 repetition costs
Age	N-2 switch (CBA)	N-2 repeat (ABA)	RT cost	N-2 switch (CBA)	N-2 repeat (ABA)	Error cost	N-2 Repetition Cost
Young	1084 (263)	1137 (260)	53 (71)	.04 (.04)	.04 (.04)	.003 (.02)	0.14 (0.45)
Old	1670 (645)	1764 (663)	94 (102)	.04 (.06)	.05 (.06)	.01 (.02)	−0.22 (0.38)