Comparative study of environmental factors influencing motor task learning and memory retention in sighted and blind crayfish.

In classical conditioning, an alteration in response occurs when two stimuli are regularly paired in close succession. An area of particular research interest is classical conditioning with a chemical signal and visual and/or tactile stimuli as the unconditional stimuli, to test manipulative and motor behaviors in a learning paradigm. A classical learning task chamber was developed to examine learning trends in a sighted surface-dwelling crayfish, Procambarus clarkii, and in a blind cave-dwelling crayfish, Orconectes australis packardi.

Bilateral symmetry in crayfish behavioral reactions.

The crayfish, Procambarus cubensis, placed in the central area of a plus-maze preferred to go forward in about 50% of trials; they chose the right or left arm in 20.7 and 18.9% of the trials, respectively.

Bioelectric field potentials of the ventilatory muscles in the crayfish.

This study investigated the pattern of the electrical field potentials recorded near the prebranchial chamber of the native crayfish Astacus leptodactylus. Inside the prebranchial chamber, the electrical waves had maximal amplitude and showed 2-4 peaks per cycle. Potentials with the same frequency but smaller amplitude and simpler shape were also recorded outside the chamber, near the edge of the carapace, and at some distance towards the caudal direction.

Heart and ventilatory measures in crayfish during environmental disturbances and social interactions.

Most animals assess the environment in which they live and alter their behavior according to various stimuli. When the animal does not make significant behavioral changes, as measured by bodily movements, the animal may be characterized as unresponsive to a given stimulus. This study demonstrates that when behavioral movements of crayfish cannot be observed, physiological measures of heart rate (HR) and ventilatory rate (VR) show dramatic changes in response to defined sensory stimuli.

Effects of black widow spider venom and latrocrustatoxin on crustacean nerve cells: electrophysiological and ultrastructural study.

1. Black widow spider venom (BWSV), or crustacean-specific toxin purified from it (named latrocrustatoxin, LCT) were lethal for the crayfish. 2.