Adaptation of action potential frequency is a common feature of neurons from various parts of the nervous system. Adaptation is thought to contribute to information coding, integration, input filtering and saving of metabolic resources. Despite intensive investigation, the kinetics of adaptation and recovery from adaptation are not fully described. The locust forewing stretch receptor (fSR) was used to investigate the kinetics of adaptation and recovery from adaptation in response to wing elevation. We have found that adaptation can be well described by a sum of two exponential decays with time constants 5.04 ± 0.6 s and 24.86 ± 2.45 s. The dependence of recovery on adaptation time was biphasic in 70% of the fSRs investigated. In these fSRs, the break point (10.54 ± 1.09 s) separates the initial linear phase from the following exponential one. These findings suggest that at least two mechanisms with different kinetics are involved in the adaptation of locust wing stretch receptor.

Keywords: locust, forewing stretch receptor, adaptation, recovery from adaptation, action potential