Histological Polarization of Lateral Giant-Fibres in the Crayfish.

Extrinsic modulation of crayfish escape behaviour.

Extrinsic systems were shown to control the excitability of the neurones which mediate tail-flip escape in the crayfish. Restraint suppresses the escape mediated by giant fibres and some, but not all, categories of non-giant mediated escape; autotomy of claws increases the excitability of non-giant mediated escape without affecting the lateral giant reflex. The effects of restraint on the later...

Excitation and habituation of the crayfish escape reflex: the depolarizing response in lateral giant fibres of the isolated abdomen.

Crayfish commonly evade capture by darting backwards when one tries to pick them up or otherwise disturbs them. They do this by sharply flexing the abdomen, the tail fan acting as a paddle; at the same time they streamline themselves by thrusting their appendages forward. Like many other escape and startle reflexes throughout the animal kingdom, this one is exceedingly labile. A crayfish held b...

The different connections and motor outputs of lateral and medial giant fibres in the crayfish.

The organization of escape behaviour in the crayfish.

Invertebrate escape reflexes have long been favoured preparations for investigating neuronal substrates of behaviour. The large size of many of their component neurones make them accessible to current micro-electrode techniques, and selection pressures for rapidity of response have probably caused them to evolve in the direction of the maximal neurological simplicity consistent with their funct...

5,7-Dihydroxytryptamine lesions of crayfish serotonin-containing neurons: effect on the lateral giant escape reaction.

The crayfish's lateral giant escape response, a relatively simple behavioral reaction, is readily modulated in certain situations. For example, when a crayfish is restrained, its lateral giant (LG) fibers--command neurons that mediate the escape response--are strongly inhibited (Krasne and Wine, 1975). Previous work (Glanzman and Krasne, 1983) had suggested that serotonin (5-HT) might mediate t...