TY  - JOUR
AB  - Synaptic transmission is usually studied in vitro with electrical stimulation replacing the natural input of the system. In contrast, we analyzed in vivo transfer of visual motion information from graded-potential presynaptic to spiking postsynaptic neurons in the fly. Motion in the null direction leads to hyperpolarization of the presynaptic neuron but does not much influence the postsynaptic cell, because its firing rate is already low during rest, giving only little scope for further reductions. In contrast, preferred-direction motion leads to presynaptic depolarizations and increases the postsynaptic spike rate. Signal transfer to the postsynaptic cell is linear and reliable for presynaptic graded membrane potential fluctuations of up to approximately 10 Hz. This frequency range covers the dynamic range of velocities that is encoded with a high gain by visual motion-sensitive neurons. Hence, information about preferred-direction motion is transmitted largely undistorted ensuring a consistent dependency of neuronal signals on stimulus parameters, such as motion velocity. Postsynaptic spikes are often elicited by rapid presynaptic spike-like depolarizations which superimpose the graded membrane potential. Although the timing of most of these spike-like depolarizations is set by noise and not by the motion stimulus, it is preserved at the synapse with millisecond precision. (C) 2003 IBRO. Published by Elsevier Science Ltd. All rights reserved.
DA  - 2003
DO  - 10.1016/S0306-4522(03)00204-5
KW  - Synapse
KW  - Neural computation
KW  - Graded potentials
KW  - Reliability
KW  - Visual motion
KW  - Spike timing
LA  - eng
IS  - 4
M2  - 1103
PY  - 2003
SN  - 0306-4522
SP  - 1103-1112
T2  - Neuroscience
TI  - Synaptic transfer of dynamic motion information between identified neurons in the visual system of the blowfly
UR  - https://nbn-resolving.org/urn:nbn:de:0070-pub-17734538
Y2  - 2024-11-22T08:02:14
ER  -