To identify the ascending spinal pathway contributing to peripheral stimulation-induced inhibition of drug-induced behaviors, we hypothesized that: 1) Selective lesions of the DC or STT pathways would affect sensory stimulation-induced inhibition of cocaine locomotor activity; 2) DC nuclei would be activated by specific peripheral stimulation; 3) Surgical transection of the DC or STT pathways would decrease the inhibition of cocaine modulation of the NAc by peripheral stimulation; 4) Peripheral stimulation would activate the lateral habenula (LHb); and 5) LHb lesions would disrupt sensory stimulation-induced effects on cocaine locomotion or neuronal activation in NAc.