The ventromedial and ventro-anterior-lateral (VM/VAL) motor thalamus is a key junction within the brain circuits sustaining normal and pathological motor control functions and decision making. In this area of thalamus, on one hand, the inhibitory nigro-thalamic pathway provides a main output from the basal ganglia, and on the other hand motor thalamo-cortical loops are involved in the maintenance of ramping preparatory activity before goal directed movements. To better understand the nigral impact on thalamic activity, we recorded electrophysiological responses from VM/VAL neurons while male and female mice were performing a delayed right/left decision licking task. Analysis of correct and error trials revealed that thalamic ramping activity was stronger for premature licks (impulsive action), and weaker for trials with no licks (omission) compared to correct trials. Suppressing ramping activity through optogenetic activation of nigral terminals in the motor thalamus during the delay epoch of the task led...