Control of the timing of behavior is thought to require the basal ganglia (BG) and BG pathologies impair performance in timing tasks. Temporal interval discrimination depends on the ramping activity of medium spiny neurons (MSN) in the main BG input structure, the striatum, but the underlying mechanisms driving this activity are unclear. Here, we combine an MSN dynamical network model with an action selection system applied to an interval discrimination task. We ﬁnd that when network parameters are appropriate for the striatum so that slowly ﬂuctuating marginally stable critical dynamics are intrinsically generated, up and down ramping populations naturally emerge which enable signiﬁcantly above chance task performance. We show that emergent population activity is in excellent agreement with multiple empirical studies and discuss how MSN network dysfunction in disease may alter temporal perception.