Figure 1.

Positioning of electrodes: characteristic response to LOT strong electrical shock. A, Extracellular recording from the granule cell layer of the olfactory bulb. B, Extracellular recording from layer I of the piriform cortex showing the monosynaptic and disynaptic (associative) components characteristic of that layer. C, Characteristic intracellular response of a layer II/III pyramidal neuron to LOT stimulation with an EPSP or spike followed by a prolonged hyperpolarization. Calibration: 1 and 0.5 mV, 20 msec (from olfactory bulb and piriform cortex, respectively); 20 mV, 50 msec for intracellular recordings. Left, Histological assessment of extracellular electrode positioning. Note that lesions in the granule cell layer of the olfactory bulb (top) and in layer I of the piriform cortex (bottom) are shown. Arrows connect areas in which recordings were performed to their characteristic response.