To obtain dendritic recording, we perform somatic whole-cell recording first and load the cell with fluorescent dye, then trace the apical dendrite and identify an appropriate location for dendritic recording. Since slices maintained in modified ACSF can generate spontaneous network activities (here Up and Down states), we use dendritic recording to examine the transfer function of the dendrite during network activity when the neuron is bombarded by massive synaptic inputs.