title: Common dynamical features of sensory adaptation in photoreceptors and olfactory sensory neurons.
abstract: Sensory systems adapt, i.e., they adjust their sensitivity to external stimuli according to the ambient level. In this paper we show that single cell electrophysiological responses of vertebrate olfactory receptors and of photoreceptors to different input protocols exhibit several common features related to adaptation, and that these features can be used to investigate the dynamical structure of the feedback regulation responsible for the adaptation. In particular, we point out that two different forms of adaptation can be observed, in response to steps and to pairs of pulses. These two forms of adaptation appear to be in a dynamical trade-off: the more adaptation to a step is close to perfect, the slower is the recovery in adaptation to pulse pairs and viceversa. Neither of the two forms is explained by the dynamical models currently used to describe adaptation, such as the integral feedback model.
authors: SISSA, International School for Advanced Studies, via Bonomea 265, 34136 Trieste, Italy.
authors: Giovanna
authors: G
authors: De Palo
authors: Giuseppe
authors: G
authors: Facchetti
authors: Monica
authors: M
authors: Mazzolini
authors: Anna
authors: A
authors: Menini
authors: Vincent
authors: V
authors: Torre
authors: Claudio
authors: C
authors: Altafini
mesh_terms: D000222:Adaptation, Physiological; D000557:Ambystoma; D000818:Animals; D018034:Olfactory Receptor Neurons / Q000502:physiology*; D010786:Photoreceptor Cells / Q000502:physiology*