The T-maze test has been used to study several entirely different issues: spontaneous alternation behavior (SAB), perseveration behavior (PB), and behavioral lateralization. Despite the fact that in this test the behavior studied is always the same one (i.e., side choice), the possible relationships among SAB, PB, and lateralization have not been previously evaluated. The present study investigated the relationships among these functions. The results demonstrated that (a) shock increases PB and lateralization but decreases SAB, (b) practice increases lateralization and decreases SAB but does not modify PB, and (c) there are sex differences for alternation and SAB. Because these functions are expressed by the same behavioral pattern, they must be quantified simultaneously to avoid mistaken conclusions when the T-maze test is used.