Fig. 1.

Infrared-guided laser stimulation.A, Set-up used for infrared-guided laser stimulation. Neurons in brain slices were visualized with transmitted infrared (IR) light and the gradient contrast system. The beam of a UV laser was focused by the objective to a 1 μm spot in the specimen plane. This way, glutamate was photolytically released from caged glutamate with high spatial and temporal resolution. The neuronal responses were recorded with patch-clamp pipettes at the soma.B, Pyramidal neuron of neocortical layer 5 visualized by infrared videomicroscopy. Scale bar, 10 μm.