TABLE 2

Effects of haloperidol and risperidone on response latencies at different stimulus durations in the five-choice serial reaction-time task

Data are presented as mean ± S.E.M.

Treatment	Latency Type	Stimulus Duration
Treatment	Latency Type	5.0 s	2.5 s	1.0 s	0.5 s
	Correct Response
Vehicle		1.10 ± 0.06	0.98 ± 0.03	0.70 ± 0.02	0.68 ± 0.03
Risperidone 1.25 mg/kg		1.41 ± 0.07^*	1.14 ± 0.04^*	0.72 ± 0.05	0.77 ± 0.06
Risperidone 2.5 mg/kg		1.50 ± 0.04^*	1.16 ± 0.04^*	0.86 ± 0.07	0.76 ± 0.07
Haloperidol 1.0 mg/kg		1.48 ± 0.09^*	na	na	na
	Incorrect Response
Vehicle		0.71 ± 0.04	1.03 ± 0.16	2.19 ± 0.0.12	1.96 ± 0.09
Risperidone 1.25 mg/kg		1.00 ± 0.04	1.50 ± 0.27	2.43 ± 0.10	2.21 ± 0.10
Risperidone 2.5 mg/kg		0.90 ± 0.08	1.63 ± 0.26	2.37 ± 0.14	2.07 ± 0.18
Haloperidol 1.0 mg/kg		0.92 ± 0.07	na	na	na
	Reward
Vehicle		1.23 ± 0.06	1.24 ± 0.08	1.22 ± 0.07	1.20 ± 0.09
Risperidone 1.25 mg/kg		1.45 ± 0.10	1.47 ± 0.16	1.28 ± 0.08	1.24 ± 0.08
Risperidone 2.5 mg/kg		1.92 ± 0.22^*	2.21 ± 0.17	2.04 ± 0.22^*	1.92 ± 0.27^*
Haloperidol 1.0 mg/kg		2.98 ± 0.38^*	na	na	na

na, not applicable (test subjects at this antipsychotic dose did not advance from the previous stimulus duration. S, second.
↵* P < 0.05; significant difference from vehicle-treated group.