In Hermissenda crassicornis, the memory of light associated with turbulence
is stored as changes in intrinsic and synaptic currents in both
type A and type B photoreceptors. These photoreceptor types exhibit
qualitatively different responses to light and current injection, and
these differences shape the spatiotemporal firing patterns that control
behavior. Thus the objective of the study was to identify the mechanisms
underlying these differences. The approach was to develop a
type B model that reproduced characteristics of type B photoreceptors
recorded in vitro, and then to create a type A model by modifying a
select number of ionic currents. Comparison of type A models with
characteristics of type A photoreceptors recorded in vitro revealed that
type A and type B photoreceptors have five main differences, three
that have been characterized experimentally and two that constitute
hypotheses to be tested with experiments in the future. See paper for more and details.
Reference:
1 .
Blackwell KT (2006) Ionic currents underlying difference in light response between type A and type B photoreceptors. J Neurophysiol 95:3060-72 [PubMed]
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