Figure 1.

Adaptation of fly visual motion-sensitive neurons. Two synaptically coupled types of neurons were simultaneously recorded in vivo during presentation of a grating pattern. Repeated identical sequences of random velocity modulations of the pattern were presented. Top, schematic of the fly head with the exposed recording site. Bottom, membrane potential responses of the presynaptic VS-neuron (right) and trains of action potentials of the postsynaptic V1-neuron (left). VS-neurons transfer signals at synapses by graded potentials. Dashed horizontal line represents resting membrane potential of VS prior to stimulation. Action potentials of V1 are indicated by vertical lines.