• mice injected with an adenovirus expressing Cre recombinase into the left auditory cortex exhibit neurons with increased dendritic total length and branch number

• mice injected with an adenovirus expressing Cre recombinase into the left auditory cortex exhibit neurons with increased density of dendritic spines

• mice injected with an adenovirus expressing Cre recombinase into the left auditory cortex have neurons that exhibit lower input resistance than nearby control neurons without adenovirus

• pyramidal neurons from mice injected with an adenovirus expressing Cre recombinase into the left auditory cortex receive stronger local inputs in the auditory cortex than control neurons without adenovirus; the increase is greatest for inputs arising from layer 2 but is present in all layers

• neurons from mice injected with an adenovirus expressing Cre recombinase into the left auditory cortex or the left auditory thalamus exhibit increased neuronal responses to auditory callosal and thalamic inputs as indicated by enhanced light-evoked EPSCs after channelrhodopsin-2 adenoviral expression (which allows for neurons to be excited to fire action potentials by flashing blue light)

• mice injected with an adenovirus expressing Cre recombinase into the left auditory cortex exhibit increased miniature spontaneous EPSC frequency and miniature EPSC amplitude