SyringesVibrissaeNeedle-Exchange ProgramsSomatosensory CortexMedical Waste DisposalSubstance Abuse, IntravenousDisposable EquipmentPharmaciesNeedlesLegislation, PharmacyLaw EnforcementEquipment ReuseThalamusAfferent PathwaysSensory DeprivationInjectionsDrug PackagingSterilizationInjections, JetDrug UsersEvoked Potentials, SomatosensoryDrug and Narcotic ControlVentral Thalamic NucleiEquipment ContaminationPrescriptionsAsepsisCommerceHIV InfectionsHarm ReductionNeuronal PlasticityCerumenModels, MolecularRisk-TakingTouchDrug StorageBlood-Borne Pathogens